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View Full Version : FW-190 vs BF-109 Werner Seitz filmclip!



DIRTY-MAC
03-17-2008, 06:10 PM
enjoy:
http://www.youtube.com/watch?v=R0YLLBvIBFk&feature=related

Also Günther Rall and Arthur Gärtner on FW-190
http://www.youtube.com/watch?v=5vO9NKJNjiw&feature=related

waffen-79
03-17-2008, 07:14 PM
thanks mate, excellent videos

Jaws2002
03-17-2008, 08:56 PM
Nice. thx.


That test against the Bf-109F4 was done with the A2.
The A2 they tested had A BMW 801C engine with all the trobles it came with.
Once the more powerful BMW-801D was installed the 190 became a very different aircraft.

Bremspropeller
03-18-2008, 06:56 AM
What Gärtner says about the plane tilting was actually a comment on the 109.

I have a DVD where his original interview (in German) can be heard and he speaks of the 109's coolant-flaps opening and closing, without the pilot being able to influence them...

Genie-
03-18-2008, 08:36 AM
.."the Fw190 could outturn the Me109 at any speed"..

heh we will never see THAT in this game for sure...

Jaws2002
03-18-2008, 08:50 AM
Originally posted by Genie-:
.."the Fw190 could outturn the Me109 at any speed"..

heh we will never see THAT in this game for sure...


Maybe because is not true. http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif

At higher speeds it makes sense but at low speed I doubt it.

Blutarski2004
03-19-2008, 02:54 PM
Depends on what was meant by "out-turning". If the definition was time required to change direction by 90 degrees, then the claim favoring the FW190 might be accurate due to its roll rate superiority.

Bremspropeller
03-19-2008, 02:55 PM
The 190 will fly circles around the 109 - at speed.

Xiolablu3
03-19-2008, 05:26 PM
Originally posted by Jaws2002:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Genie-:
.."the Fw190 could outturn the Me109 at any speed"..

heh we will never see THAT in this game for sure...



Maybe because is not true. http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif

At higher speeds it makes sense but at low speed I doubt it. </div></BLOCKQUOTE>

Yeah, the doc got it wrong.

There is no way a FW190 with its wingloadsing could outturn a Bf109 with slats at low speeds.

The documentary writer is another one who misunderstood 'more manouverable'

In a close in classic dogfight, the Me109 could out turnfight the Fw190. There is a mock combat report between FW190's and Bf109's somewhere, the Bf109's won out easily, even when starting from below.

The FW190 has to be flown right to have its superiority, that means energy fighting, as in the sim. If he stuck around to dogfight/turnfight then the better turning plane would win.

HuninMunin
03-19-2008, 05:34 PM
The Fw 190 could outturn the 109 with ease above 350 km/h.
Although it had a big turn radius it had a very high turnrate over a rather larg band of speeds.

To outturn means to alter the direction of movement faster then a given opponent.
Taking the rollrate and turnrate into account, I have no doubt that the 190 could very easily outturn a trailing 109 in a brake and / or force a gun sollution on a 109 by superior turn performence.

Xiolablu3
03-19-2008, 05:35 PM
Found the report :-

'Report from JG 11 on 29th [October 1944] on mock air battle between Fw 190A-9 and Bf 109 AS/MW 50.

A Schwarm of Me 109 at 8,000 metres climbed up to attack a Rotte of Fw 190 at 10,000 metres. On the turn with 1.1 boost, the Me 109 Schwarm out climbed the Fw 190 Rotte by about 200 metres and at the same time without fully opened throttles and not flying flat out, they out turned the Fw 190 Rotte.

First attack was from above and behind with 1.1 boost and flaps retracted and a normal steep turn without opening to maximum possible speed, the Fw 190A-9 was easily overtaken and out turned.

Second attack from behind and below on the number one of the Rotte, aircraft was easily overtaken, out turned and outstripped in the inside turn.

On full throttle it is easily possible to out climb the A-9 without losing position since speed can be reduced by throttling back and doing very tight turns.'


I guess this is at the BF109's better height however.

Vike
03-19-2008, 06:15 PM
Originally posted by Xiolablu3:
I guess this is at the BF109's better height however.

Indeed at high alt,the Antons suffer a tremendous lack of power,when the DB605s still continue to provide power...
Exactly as in the sim. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

As in the sim or IRL,the Late-Me109s have their little drawbacks,but once you know them by heart,the Late-Me109s fit you like a glove from 0m till 10000m+ and give you all the means to defeat *any* opponent. http://forums.ubi.com/images/smilies/halo.gif

Things that,from my OnLine observations,cannot be applied to a Fw190-Anton. http://forums.ubi.com/images/smilies/16x16_smiley-indifferent.gif

@+

Bremspropeller
03-20-2008, 07:04 AM
Xio, please do me a favor and stop using wingload as a reference.

Wingload is ONE factor of the equation - not just the factor.

Whereas those 109s might have outdanced the 190s at alt (anything above 7000m is not Focke-Wulf country), there are reports on 190s easily taking up 109 in mock-fights (that includes F versions of the 190) - at alts between 6000m and GND.
Egon Mayer and Julius Meimberg made their very own show out of it. None of them won - that was b/c both knew their planes (and the other plane) to the limits. They knew when to press on and when to relax and get into a better position.
After half an hour of doghfighting, both landed, none really ever having had the chance to score.
They were barely able to climb out of their planes as the whole mock-fight was that exhausting (now talk about our DF-servers).

Generally the 190 was superrior in everything but turn at low speeds and alt performance.

The 190 would out-range, out-gun, out-accelerate, out-fall, out-zoom and out-handle any 109, any day.
And it would bring you home across the channel with two pistons knocked out, oil spitting all over your cowling and canopy.

While the 109 was a good fighter per design, it clearly lacked behind in performance and ability (concerning it's tactical worth to the war on the ground).
The 190, however, clearly was what the Luftwaffe actually wanted right from the start: a multi-mission plane.

A real shame, they never realized it's alt-deficencies in-time. Udet cancelled all attempts to design a high-alt capable Fw 190 - that was in '41.
In '43, the allies appreciated that decision, which was nothing but leaving the "Fortress Europe" without a roof...

Xiolablu3
03-20-2008, 08:58 AM
I'm not sure I agree with your comment about the FW190's all-round superiority, you say yourself that the FW190 was not good above 7000m, whereas the Bf109 was.

Its the way the planes are used which is the all important factor. ON the Eastern front the Bf109 was much more respected than the Fw190.

I dont think either plane was 'better', each one had some characteristics better than the other.

ALso wingloading is a very important factor in turn performance. Many would say the most important factor as long as things like Slats are not present.

Bremspropeller
03-20-2008, 09:19 AM
Yeah, many armchair physicians agree, mainly those you find on this board http://forums.ubi.com/groupee_common/emoticons/icon_rolleyes.gif

I'm tired of telling ppl why comparing wingloads of two entirely different a/c with entirely different profiles and lift curves is BS... http://forums.ubi.com/images/smilies/compsmash.gif

=============

As for the 109 being more respected..
It was by the russians, but only b/c they didn't know sh1t about tactics and sticked to turn-fights at low alt. Most 190s they encountered were fighter-bombers with crews that were trained for ground-attack.

Pilots that were agressive showed the Russians how off their their conclusion was.
August Lambert is one of those.

JG 54 was the second highest scoring wing of the war - it was only beaten by JG 52 which was operating in a more target-rich environment.

Most pilots agree, the 190 was the better fighter, fighter-bomber and aircraft as such.

There was a reason why most of the 190s were sent to the western front at the start - they were the better fighters for the conditions met there.

Jaws2002
03-20-2008, 10:20 AM
[QUOTE]Originally posted by Bremspropeller:


Generally the 190 was superrior in everything but turn at low speeds and alt performance.

The 190 would out-range, out-gun, out-accelerate, out-fall, out-zoom and out-handle any 109, any day.

QUOTE]

As much as I like the 190, I haven't heared of the FW-190 out zooming the 109.
And is safe to say that climb is an extremely important part of the game and the 109 dominated from ground to the heavens in this respect.

On the other hand about that "fight" between Egon Mayer and Julius Meimberg, the 109 Julius flew had the weapons and armor removed, as it was suposed to be sent to the factory for some upgrades.

So i'd come to the conclusion that this two were great planes that complemented eachother well on the battlefield.

Bremspropeller
03-20-2008, 11:00 AM
As much as I like the 190, I haven't heared of the FW-190 out zooming the 109.
And is safe to say that climb is an extremely important part of the game and the 109 dominated from ground to the heavens in this respect.

It does.
It's heavier and has a better thrust-output, which can cleary be seen by the 190 easily outaccelerating the 109.

Zooming means translating kinetic energy into static energy, which means trading speed for alt.
We're not talking of sustained climbs here.

Bewolf
03-20-2008, 11:08 AM
Originally posted by Bremspropeller:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">As much as I like the 190, I haven't heared of the FW-190 out zooming the 109.
And is safe to say that climb is an extremely important part of the game and the 109 dominated from ground to the heavens in this respect.

It does.
It's heavier and has a better thrust-output, which can cleary be seen by the 190 easily outaccelerating the 109.

</div></BLOCKQUOTE>

In real life maybe...not in this game =)
But we've been there.

FatCat_99
03-20-2008, 12:44 PM
Originally posted by Bremspropeller:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">As much as I like the 190, I haven't heared of the FW-190 out zooming the 109.
And is safe to say that climb is an extremely important part of the game and the 109 dominated from ground to the heavens in this respect.

It does.
It's heavier and has a better thrust-output, which can cleary be seen by the 190 easily outaccelerating the 109.

Zooming means translating kinetic energy into static energy, which means trading speed for alt.
We're not talking of sustained climbs here. </div></BLOCKQUOTE>

Acceleration and zooms are all about specific excess power and 109 beats 190 easily in that department.

BTW weight doesn't help you in zoom climb, FW have more drag than 109 so any advantage in thrust is offset by higher drag and weight.

Russians have tested acceleration of different planes or you can do calculation and see yourself.

Science and tests say something different than you.

FC

Bremspropeller
03-20-2008, 12:51 PM
Acceleration and zooms are all about specific excess power and 109 beats 190 easily in that department.

Really? So, tell me why I alwas read about 190s accelerating and zooming away from 109s.


BTW weight doesn't help you in zoom climb

No? Google for a guy called "Newton". He might have some surprises for you.

FatCat_99
03-20-2008, 01:26 PM
Originally posted by Bremspropeller:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Acceleration and zooms are all about specific excess power and 109 beats 190 easily in that department.

Really? So, tell me why I alwas read about 190s accelerating and zooming away from 109s.


BTW weight doesn't help you in zoom climb

No? Google for a guy called "Newton". He might have some surprises for you. </div></BLOCKQUOTE>

Why don't you surprise me and world with your interpretation of physics. Newton is old and boring and I have a feeling that you have something new and refreshing.

Or you can take Shaw's Fighter tactic and take a look at page 394, there is something about thrust, drag, weight, velocity and how they affect specific excess power.

Of course you can take any other book about mechanics of flight but it's important to read them, having them on bookshelf doesn't help much. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

FC

Bremspropeller
03-20-2008, 02:13 PM
Alright I've read the passage.
I see your point, but Shaw doesn't mention the effect of weight and inertia for overcoming drag.

The heavier fighter has less excess power, but it has the higher initial energy.
Therefore, the heavier fighter will initially have an adantage. the fighter with higher excess-power will catch up and (maybe) pass on.

My point was, the 190 has the better thrust output (obviusly, as it accelerated away from the 109s in pretty much any test/ comparison I've seen so far) and also has the higher weight.
In level-acceleration, weight is unimportant (if we don't take induced/ lift-drag into consideration). The only forces of interest are thrust:drag.

By your logic of having more drag, the 190 has to have a LOT more thrust than the 109 (for the reason given above) - leading to it's acceleration superriority.

Unfortunately, there are no thrust-figures out for those planes, so all we can do is rely on reports.

Kettenhunde
03-20-2008, 04:20 PM
Acceleration and zooms are all about specific excess power and 109 beats 190 easily in that department.

Absolutely correct. However there are conditions of flight where the FW190 has more specific excess power and easily beats the 109 in that department.

Just as there are conditions the 109 beats the 190.

Bremspropeller, weight figures by increasing the drag due to lift requirement.

The FW190 out zooms the Bf-109 only in the fact generally speaking, the FW190 has to maintain a faster velocity than the Bf-109.

Velocity is the main characteristic of a zoom if you do a parametric study.

Generally speaking, in order for the Bf-109 to use its turn advantage, it has to fly slower than the FW190. Remember, turn performance is very much related to the stall line and the Bf-109 stall line occurs at a slower velocity than the FW190.

That generalization goes pretty much for any aircraft as all aircraft at the same angle of bank and velocity will make exactly the same turn. There is a very sound scientific reason designers seek agility over level turn performance. This is where it really helps to have practical experience in a cockpit. It really helps to bring the aerodynamics of aircraft turn performance into focus and to tie it all together. If you just look at one characteristics of a design, you will most likely draw the wrong conclusion.

There are not many conditions of flight that the FW190 could not place its vector of lift below the horizon and overcome the 109's advantage too. The dirt barrier being the key condition.


Yeah, the doc got it wrong.

No it did not. The document and pilots are correct in what they observed in air.

However this is only for a specific condition of flight.

The FW190 and Bf-109 at the same angle of bank and velocity will make exactly the same turn. However the aircraft that can establish the turn the fastest will also complete the turn the fastest.


There is no way a FW190 with its wingloadsing could outturn a Bf109 with slats at low speeds.

Correct! However this is only for a specific condition of flight.

If we conduct all of our flying in those specific conditions then we can make some absolute statements!


All the Best,

Crumpp

Xiolablu3
03-20-2008, 04:34 PM
Hi Crump,

Where I wrote 'the doc got it wrong' was the part about the Fw190 being able to outturn the FW190 at all speeds and outroll it at all speeds.

I was sure that he Bf109 would outturn the Fw190 at low speeds, the doc says that the FW190 could outturn the Bf109 'at all speeds'.

Is the doc correct in this point?

Kettenhunde
03-20-2008, 05:04 PM
Hi Xio,


I was sure that he Bf109 would outturn the Fw190 at low speeds, the doc says that the FW190 could outturn the Bf109 'at all speeds'.

Depends on what "low speeds" are but yes, the Bf-109 can fly at a slower velocity and will easily outturn the FW190 near the 190's stall line.

Werner Seitz might have very well meant, "at all speeds that we flew." He probably did not clarify that as to him it would seem an obvious statement. That's just a guess though as I have not talked to the man.

Combat is a very bad place to practice slow flight and I don't imagine that many who did it on regular basis lived to tell about it.

All the best,

Crumpp

Xiolablu3
03-20-2008, 05:15 PM
Thanks for your reply, however its not the German vets who say this, but the narrator, which was why I thought he got it wrong.

Did you watch the 1st clip?

BTW is your FW190 flying now?

Kettenhunde
03-20-2008, 05:43 PM
however its not the German vets who say this, but the narrator, which was why I thought he got it wrong.

You are correct. It is the narrator and not Werner Seitz. Seitz only relates that the aircraft was wonderful in the turn.

That does not invalidate the point that for 99% of the envelope, there is no difference in these airplanes ability to turn. The major difference is in their ability to establish a turn and change direction. That 1% was not a portion of the envelope many fighter pilots actively sought to fly in.

No countries Air Force went, OMG, our fighter does not outturn their fighter at low speed.....Bad design junk it now!

Just think how different the Air War in the Pacific would have been if the United States had said that!

On White 1, We have all the parts built and are jigging the wings now. We are on schedule to fly in early 2009.

All the best,

Crumpp

Xiolablu3
03-20-2008, 06:01 PM
I understand your points, howevr I know for a fact that RAF pilots loved the fact that the Spitfire turned so well.

For example here is Irving 'Hap' kennedy' talking about his new SPitfire IX.

'I had the throttle open and I rolled over and headed on a course to
cut the angle toward the 109s, which had separated a little. I wound on
nose-heavy trim so essential to keep the aircraft in a high-speed dive.
The Spit responded eagerly as I dove more steeply than the 109s, with
Red Two and Three no doubt following, although I could not see them. The
controls got very heavy as the airspeed needle moved far right at 480
mph. (Corrected for altitude, true airspeed approached 600 mph.) I could
see that I was gaining on the nearest Me 109. That was something new. We
were already half-way to Sicily; that was no problem. We knew from years
of experience, dating back to the boys who had been in the Battle of
Britain, that the 109 with its slim thirty-two foot wing was initially
faster in a dive than we were.

***But we accepted that compromise happily
in exchange for our broad superior-lift wing with its better climb and
turn. One couldn't have it both ways.***

In any case, I was closing on this
Me 109, which I recognised as a G. Perhaps he wasn't using full
throttle.'

Although perhaps not the most important factor in air combat, a better turn is still extremely useful, particularly in a close-in dogfight, or if cannot just B&Z and you have to stick around and fight it out, for example when escorting bombers..

T%he Japanese ruled supreme in the early days of the war with their fantastic dogfighters/turners like the Zero and Ki43, and the Bf109 gained rounded wings with extra surface in its later marks from the F onwards, which we know from the clipped SPitfires reduce roll rate but enable a better turn as they have more wing area.

Kettenhunde
03-20-2008, 06:36 PM
RAF pilots loved the fact that the Spitfire turned so well.

Of course they love their airplanes. It took care of them.


T%he Japanese ruled supreme in the early days of the war with their fantastic dogfighters/turners like the Zero

The Zeke was one of the fastest airplanes in the pacific theater early in the war.

All the best,

Crumpp

Bremspropeller
03-20-2008, 06:47 PM
The Spit didn't just turn well, it was a good allround fighter.
Some 109 pilots believed they could turn just as well as a Spit, however.

It comes down to pilot ability and experience...some 109 pilots even dared to turn with Yaks (with success!) - and Yaks fly circles around pretty much anything...well, save some japaneese fighters.
That doesn't imply that any 109-driver could perform that stunt, however.

Kettenhunde
03-20-2008, 06:50 PM
pilots even dared to turn with Yaks

Oskar Bösch turned with every fighter victory he was awarded in an R7/R8 variant.

All the best,

Crumpp

Bremspropeller
03-20-2008, 06:59 PM
And that includes some Yaks:
http://www.luftwaffe.cz/bosch.html

Not bad for a Sturmbock-driver http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

I've seen some pictures of Oskar being at some US airshow, a few years back...

Do you know if he's still with us and doing well?

AFAIK, he had a nice glider-career after the war.

Kettenhunde
03-20-2008, 07:03 PM
***But we accepted that compromise happily
in exchange for our broad superior-lift wing with its better climb and
turn. One couldn't have it both ways.***


BTW, I don't understand what is meant by this statement. There is nothing mutally exclusive or incompatible with the characteristics of dive aceleration, mach limits, q-limits, and climb/turn.

All the best,

Crumpp

Kettenhunde
03-20-2008, 07:06 PM
Do you know if he's still with us and doing well?

He is doing just fine and is sharp as ever. I very much enjoy our discussion's although they have little to do with WWII Airplanes anymore. He is a true gentleman.

The Smithsonian made an IMAX film that features Oskar's performance.

His website:

http://www.avialantic.com/performers/oscar.html

All the best,

Crumpp

Xiolablu3
03-20-2008, 07:07 PM
Yeah, I understand that turning is not the most important factor in air combat, however it is/was often used to win dogfights, and kills were made as a result of outturning the opponent.

The point I am trying to make is that having a superior turn IS very useful in air combat in cetain situations.

Just a couple of examples of air combats won with better turn performance :-

'S/L Colin Gray, with No. 81 Squadron flying Spitfire IXs in North Africa,
commented on a 3 April 1943 combat:
We were just taking off from Paddington for a diversionary sweep when
the airfield was attacked without any warning whatsoever by a gaggle of
bomb-carrying Focke Wulf 190s. Half a dozen of us were airborne, but the
rest were still on the runway when the bombs fell, but fortunately they
did not do any serious damage. I was about to land back again with a
duff engine, but when I saw the bombs fall I immediately set off in hot
pursuit of the invaders. I did not have much hope of catching them as
the 190s had the legs on us at ground level and they had a head start
from their dive, not to mention my duff engine. I chased them up the
Beja road towards Tabarka, but the further we went the further they got
ahead, so I eventually gave up the attempt and turned back for home.
Just as I completed my turn I saw another aircraft coming towards me at
high speed, and as he flashed past I recognized a 109G2. He also
obviously recognized me as hostile because he immediately pulled into a
screaming left-hand turn and attempted to dogfight. This was a big
mistake because there was no way a 109 could turn inside a Spitfire. It
took only a few minutes to get on his tail and a short burst with cannon
and machine-guns produced much smoke, glycol, and large chunks falling
off. The pilot immediately pulled up and bailed out, but we were still
close to the ground, and although his parachute appeared to stream, it
did not open before the poor beggar hit the ground. Almost at the same
time I heard a yell over the R/T from Paul Hagger announcing that he too
had also just knocked down another 109.'

Pierre Clostermann :-

'I opened the throttle flat out and threw my Spitfire into a very
steep climbing turn which enabled me to keep my eyes on him and to gain
height. Taken by surprise by my manoervre, he opened fire, but too late.
Instead of the slight 5? deflection he was expecting, I suddenly
presented him with a target at 45?. I leveled out and continued my tight
turn. The "109" tried to turn inside me, but at that height his short
wings got insufficient grip on the rarefied atmosphere and he stalled
and went into a spin. Once again the Spitfire's superior manoeuvrability
had got me out of the wood.

The Messerschmitt came out of his spin. But I was already in
position, and he knew it, for he started hurling his machine about in an
effort to throw off my aim. His speed availed him nothing, however, for
I had profited by his previous false move to accelerate and now I had
the advantage of height. At 450 yards range I opened fire in short
bursts, just touching the button each time. The pilot of the "109" was
an old fox all the same, for he shifted his kite about a lot, constantly
varying the deflection angle and line of sight.
He knew that my Spitfire turned better and climbed better, and that
his only hope was to out-distance me. Suddenly he pushed the stick
foward and went into a vertical dive. I passed onto my back and, taking
advantage of his regular trajectory, opened fire again. We went down
fast, 470 m.p.h. towards Aumale. As I was in line with his tail the
firing correction was relatively simple, but I had to hurry - he was
gaining on me.
At the second burst three flashes appeared in his fuselage - the
impact visibly shook him. I fired again, this time hitting him on the
level with the cockpit and the engine. For a fraction of a second my
shell bursts seemed to stop the engine. His propeller suddenly stopped
dead, then disppeared in a white cloud of glycol bubbling out of the
exhausts. Then a more violent explosion at the wing root and a thin
black trail mingled with the steam gushing from the perforated cooling
system.'

Jaws2002
03-20-2008, 08:43 PM
Originally posted by Xiolablu3:
Yeah, I understand that turning is not the most important factor in air combat, however it is/was often used to win dogfights, and kills were made as a result of outturning the opponent.

The point I am trying to make is that having a superior turn IS very useful in air combat in cetain situations.

Just a couple of examples of air combats won with better turn performance :-

'S/L Colin Gray, with No. 81 Squadron flying Spitfire IXs in North Africa,
commented on a 3 April 1943 combat:
We were just taking off from Paddington for a diversionary sweep when
the airfield was attacked without any warning whatsoever by a gaggle of
bomb-carrying Focke Wulf 190s. Half a dozen of us were airborne, but the
rest were still on the runway when the bombs fell, but fortunately they
did not do any serious damage. I was about to land back again with a
duff engine, but when I saw the bombs fall I immediately set off in hot
pursuit of the invaders. I did not have much hope of catching them as
the 190s had the legs on us at ground level and they had a head start
from their dive, not to mention my duff engine. I chased them up the
Beja road towards Tabarka, but the further we went the further they got
ahead, so I eventually gave up the attempt and turned back for home.
Just as I completed my turn I saw another aircraft coming towards me at
high speed, and as he flashed past I recognized a 109G2. He also
obviously recognized me as hostile because he immediately pulled into a
screaming left-hand turn and attempted to dogfight. This was a big
mistake because there was no way a 109 could turn inside a Spitfire. It
took only a few minutes to get on his tail and a short burst with cannon
and machine-guns produced much smoke, glycol, and large chunks falling
off. The pilot immediately pulled up and bailed out, but we were still
close to the ground, and although his parachute appeared to stream, it
did not open before the poor beggar hit the ground. Almost at the same
time I heard a yell over the R/T from Paul Hagger announcing that he too
had also just knocked down another 109.'

Pierre Clostermann :-

'I opened the throttle flat out and threw my Spitfire into a very
steep climbing turn which enabled me to keep my eyes on him and to gain
height. Taken by surprise by my manoervre, he opened fire, but too late.
Instead of the slight 5? deflection he was expecting, I suddenly
presented him with a target at 45?. I leveled out and continued my tight
turn. The "109" tried to turn inside me, but at that height his short
wings got insufficient grip on the rarefied atmosphere and he stalled
and went into a spin. Once again the Spitfire's superior manoeuvrability
had got me out of the wood.

The Messerschmitt came out of his spin. But I was already in
position, and he knew it, for he started hurling his machine about in an
effort to throw off my aim. His speed availed him nothing, however, for
I had profited by his previous false move to accelerate and now I had
the advantage of height. At 450 yards range I opened fire in short
bursts, just touching the button each time. The pilot of the "109" was
an old fox all the same, for he shifted his kite about a lot, constantly
varying the deflection angle and line of sight.
He knew that my Spitfire turned better and climbed better, and that
his only hope was to out-distance me. Suddenly he pushed the stick
foward and went into a vertical dive. I passed onto my back and, taking
advantage of his regular trajectory, opened fire again. We went down
fast, 470 m.p.h. towards Aumale. As I was in line with his tail the
firing correction was relatively simple, but I had to hurry - he was
gaining on me.
At the second burst three flashes appeared in his fuselage - the
impact visibly shook him. I fired again, this time hitting him on the
level with the cockpit and the engine. For a fraction of a second my
shell bursts seemed to stop the engine. His propeller suddenly stopped
dead, then disppeared in a white cloud of glycol bubbling out of the
exhausts. Then a more violent explosion at the wing root and a thin
black trail mingled with the steam gushing from the perforated cooling
system.'

In both examples the Spit was slower then the 109, so was closer to it's best turn speed. Was the second fight at high altitude? If yes then again more things to complicate the ecuation. http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif


Nitpicking. http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif

Kettenhunde
03-20-2008, 09:23 PM
The point I am trying to make is that having a superior turn IS very useful in air combat in cetain situations.


Certainly. Oskar used it quite effectively.

Remember, at the same angle of bank and velocity, that Sturmbrock makes exactly the same turn as the Spitfire.

All the best,

Crumpp

Kettenhunde
03-20-2008, 09:29 PM
Just to illustrate how much influence pilot skill has on performance let's take a look at the JFC evaluation of the F6F Hellcat.

Keep in mind that the aircraft was in the same configuration for each pilot. The largest variable in the aircraft's stall speed was the pilot's skill.

http://img222.imageshack.us/img222/7704/f6fstallfp2.jpg (http://imageshack.us)


All the best,

Crumpp

TX-Gunslinger
03-20-2008, 10:35 PM
This second page has been a great discussion.

I like what Kettenhunde just brought to the thread.

Pilot skill? JG11 in Autumn 1944?

Be great to see the same scenario played out with 4 and 5 staffel plus Stab of II/JG26 in July 1943.

A different outcome would have occurred, I think.

Generalization is the death of understanding.

S~

Gunny

Xiolablu3
03-21-2008, 11:48 AM
Originally posted by Jaws2002:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Xiolablu3:
Yeah, I understand that turning is not the most important factor in air combat, however it is/was often used to win dogfights, and kills were made as a result of outturning the opponent.

The point I am trying to make is that having a superior turn IS very useful in air combat in cetain situations.

Just a couple of examples of air combats won with better turn performance :-

'S/L Colin Gray, with No. 81 Squadron flying Spitfire IXs in North Africa,
commented on a 3 April 1943 combat:
We were just taking off from Paddington for a diversionary sweep when
the airfield was attacked without any warning whatsoever by a gaggle of
bomb-carrying Focke Wulf 190s. Half a dozen of us were airborne, but the
rest were still on the runway when the bombs fell, but fortunately they
did not do any serious damage. I was about to land back again with a
duff engine, but when I saw the bombs fall I immediately set off in hot
pursuit of the invaders. I did not have much hope of catching them as
the 190s had the legs on us at ground level and they had a head start
from their dive, not to mention my duff engine. I chased them up the
Beja road towards Tabarka, but the further we went the further they got
ahead, so I eventually gave up the attempt and turned back for home.
Just as I completed my turn I saw another aircraft coming towards me at
high speed, and as he flashed past I recognized a 109G2. He also
obviously recognized me as hostile because he immediately pulled into a
screaming left-hand turn and attempted to dogfight. This was a big
mistake because there was no way a 109 could turn inside a Spitfire. It
took only a few minutes to get on his tail and a short burst with cannon
and machine-guns produced much smoke, glycol, and large chunks falling
off. The pilot immediately pulled up and bailed out, but we were still
close to the ground, and although his parachute appeared to stream, it
did not open before the poor beggar hit the ground. Almost at the same
time I heard a yell over the R/T from Paul Hagger announcing that he too
had also just knocked down another 109.'

Pierre Clostermann :-

'I opened the throttle flat out and threw my Spitfire into a very
steep climbing turn which enabled me to keep my eyes on him and to gain
height. Taken by surprise by my manoervre, he opened fire, but too late.
Instead of the slight 5? deflection he was expecting, I suddenly
presented him with a target at 45?. I leveled out and continued my tight
turn. The "109" tried to turn inside me, but at that height his short
wings got insufficient grip on the rarefied atmosphere and he stalled
and went into a spin. Once again the Spitfire's superior manoeuvrability
had got me out of the wood.

The Messerschmitt came out of his spin. But I was already in
position, and he knew it, for he started hurling his machine about in an
effort to throw off my aim. His speed availed him nothing, however, for
I had profited by his previous false move to accelerate and now I had
the advantage of height. At 450 yards range I opened fire in short
bursts, just touching the button each time. The pilot of the "109" was
an old fox all the same, for he shifted his kite about a lot, constantly
varying the deflection angle and line of sight.
He knew that my Spitfire turned better and climbed better, and that
his only hope was to out-distance me. Suddenly he pushed the stick
foward and went into a vertical dive. I passed onto my back and, taking
advantage of his regular trajectory, opened fire again. We went down
fast, 470 m.p.h. towards Aumale. As I was in line with his tail the
firing correction was relatively simple, but I had to hurry - he was
gaining on me.
At the second burst three flashes appeared in his fuselage - the
impact visibly shook him. I fired again, this time hitting him on the
level with the cockpit and the engine. For a fraction of a second my
shell bursts seemed to stop the engine. His propeller suddenly stopped
dead, then disppeared in a white cloud of glycol bubbling out of the
exhausts. Then a more violent explosion at the wing root and a thin
black trail mingled with the steam gushing from the perforated cooling
system.'

In both examples the Spit was slower then the 109, so was closer to it's best turn speed. Was the second fight at high altitude? If yes then again more things to complicate the ecuation. http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif


Nitpicking. http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif </div></BLOCKQUOTE>

I am not using the examples to prove that the SPitfire was the better turner, just that better turning often was used to win in combat.

It could easily have been the Bf109 doing the kills, but I dont have any luftwaffe combat reports to look through and find them. Also I dont speak any German. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

FatCat_99
03-21-2008, 12:09 PM
Originally posted by Kettenhunde:

Generally speaking, in order for the Bf-109 to use its turn advantage, it has to fly slower than the FW190. Remember, turn performance is very much related to the stall line and the Bf-109 stall line occurs at a slower velocity than the FW190.

That generalization goes pretty much for any aircraft as all aircraft at the same angle of bank and velocity will make exactly the same turn.

That's true but better turning plane have choice between keeping same radius and flying faster through the turn or to keep speed and fly tighter and in both scenarios out turn other plane.


There is a very sound scientific reason designers seek agility over level turn performance. This is where it really helps to have practical experience in a cockpit. It really helps to bring the aerodynamics of aircraft turn performance into focus and to tie it all together. If you just look at one characteristics of a design, you will most likely draw the wrong conclusion.

Agree 100%,IMO having balanced plane is crucial in making the plane good war machine.


There are not many conditions of flight that the FW190 could not place its vector of lift below the horizon and overcome the 109's advantage too. The dirt barrier being the key condition.

By placing nose below horizon you are giving up E for angles, in that situation routine respond for 109 would be to go for E and transform fight from turning fight into E fight with advantage for 109.



The FW190 and Bf-109 at the same angle of bank and velocity will make exactly the same turn. However the aircraft that can establish the turn the fastest will also complete the turn the fastest.

In some situations, useful for quick gun solutions but for prolonged turning fight roll rate advantage is usually to small.



Just to illustrate how much influence pilot skill has on performance let's take a look at the JFC evaluation of the F6F Hellcat.

Keep in mind that the aircraft was in the same configuration for each pilot. The largest variable in the aircraft's stall speed was the pilot's skill.


Interesting that you mentioned this, I just found in one of the articles in Air International that estimations was that in planes with good spin prevention devices it is possible to use up to 40%more of lift potential.

http://img134.imagevenue.com/loc865/th_22586_2843145540098921485QHlOrs_fs_122_865lo.jp g (http://img134.imagevenue.com/img.php?image=22586_2843145540098921485QHlOrs_fs_1 22_865lo.jpg)

And it seems to me that F6F data from Joint Fighter Conference support that thesis.

FC

Kettenhunde
03-21-2008, 03:30 PM
keeping same radius and flying faster through the turn

Velocity and radius are linked. Least that is what I was taught in all the Aerodynamic and Aircraft performance classes I took for my degree. How are we going to increase our airplanes velocity without affecting the radius?

Our aircraft's design particulars determine the sustainable angle of bank. However we can easily do a quick parametric study to determine the effects of increasing our velocity.

Two aircraft traveling at 200Kts make a 65 degree bank.

Radius of turn:

R = Vk^2 / (11.26 * tanAoB)

200^2 / 11.26 * 65 = 1656.5 ft

1656.5 ft radius

Rate of Turn

(1091 * tan 65) / 200 = 11.7 deg/sec

30 seconds to complete a 360 degree turn.

210^2 / (11.26 * tan 65)

Radius = 1826 ft

A 170 ft increase in radius!!!

Well he is not going to outturn anything by increasing his speed!

Let's see the effect on Rate of turn. That increase in speed should help somewhat.

(1091 * tan 65) / 210 = 11.14deg/sec

32 seconds to complete a 360 degree turn.

Well that did not work either. We have increased our rate of turn not decreased it and are going through our circle at .56 degrees a second less than before! Not really going to be noticeable but with that increase in radius, we are not going to be really outturning anything that could match the original parameters.

The airplane with slower stall speed generally speaking must go slower if he is to outturn his opponent. He must bring the fight down to the vicinity of the less capable at sustained turn performance aircrafts stall speed before any real turn advantage is realized.

Since we know that velocity is the key to zoom climb performance, the moment one opponent begins to be outturned, he can zoom above his opponent. This works in general for all aircraft. If he has not given up altitude, then he will be above his better turning opponent.

Studying these pages might help to shed some insight!


http://selair.selkirk.bc.ca/aerodynamics1/Lift/Page13.html


Keep in mind that the radius of turn equation is universal, therefore this graph is valid for any airplane, from a C-150 to a Boeing 747.

http://selair.selkirk.bc.ca/aerodynamics1/Lift/Min_Radius.html


By placing nose below horizon you are giving up E for angles, in that situation routine respond for 109 would be to go for E and transform fight from turning fight into E fight with advantage for 109.

Sure you are giving up some E for angles. It does not matter as long as you get gun solution. Remember, fighter aircraft are not playing a game of tag. Once solution is met, the other aircraft does not become "it" with the whole process starting anew. The other aircraft dies in the real world.

As for transitioning, the aircraft dropping his nose is increasing it's sustainable load factor. The idea is to change it's sustainable angle of bank and not it's velocity.

The other aircraft is still going slower in it's turn. If both aircraft zoom, the faster aircraft will zoom the farther distance.

That is exactly the science behind how Focke Wulf pilots fought Spitfires successfully in close quarter dogfights. This works for F6F's vs. Zeke's, P47's vs 109's, or any scenario where an opponent has a slower stall speed and better sustained turn performance.

Good level turn performance is a very useful defense maneuver and is seen as such by designers. It is not much use on the offense unless the opponent decides to play that game.


keep speed and fly tighter

I know what you meant FatCat. This is the scenario the better turning aircraft can do. He is keeping his velocity but can choose from a higher angle of bank. This will result in in him outturning the other plane.

He is not increasing his velocity if he wants to outturn his opponent. So there is not "two" things the aircraft with better sustained turn performance can do, there is only one!

However the range of angles of bank that this superiority is exhibited is a very small portion of the envelope. Until the dirt barrier is reached, the other aircraft can still gain angles if he wishes.

The largest influence on turn performance is going to be the aircraft velocity. Generally speaking, the superior turning aircraft is the slower velocity aircraft.

All the best,

Crumpp

<edited for clarity>

Kettenhunde
03-21-2008, 03:41 PM
Interesting that you mentioned this, I just found in one of the articles in Air International that estimations was that in planes with good spin prevention devices it is possible to use up to 40%more of lift potential.


Nice article. Your Angle of Attack limiter in WWII was good stability and control design. Generally speaking, we need our ailerons/rudder to remain effective past the stall point and our elevator to lose effectiveness as we approach our 1g level stalling velocity. The next largest influence in our spin prevention is how skilled the pilot is at keeping the ball centered and wings level when the aircraft is bouncing in the buffet.


In some situations, useful for quick gun solutions but for prolonged turning fight roll rate advantage is usually to small.

Roll rate is an aircraft's agility. It represents the airplanes ability to change the orientation of the entire vector of lift. It represents how fast an aircraft can transition from one condition of flight to another.

Sustained turn performance represents an aircraft's performance under one condition of flight and one condition of flight only.

All the best,

Crumpp

DustyBarrels77
03-21-2008, 05:54 PM
you have to realize they are not refering to thier airspeeds but they are speaking about cruise and higher speeds mid to high alt (majority of combat situations), so many aircraft out turned the 109 in those mid to higher speed catagories but not low speed. I've seen these interviews before but havent in a long time thanks for posting them.

Kettenhunde
03-22-2008, 07:12 AM
so many aircraft out turned the 109 in those mid to higher speed catagories but not low speed.

Hi DustyBarrels77,

Generally speaking, low speed is where we will find our combat significant turning differences once the turn is established. Of course the shape of the actual L/D curve can reveal differences in specific performance depending on where our Px max point occurs. Remember all aircraft performance occurs at a specific velocity.

It takes a significant shift in this point though to be noticeable in the air. That's the sticking point for most gamers. It takes some rather large differences for anything to be recognizable in the air.

All the best,

Crumpp

Bremspropeller
03-22-2008, 09:27 AM
The point about pulling the same Gs for different planes (let's take a P-47 and a Ki-43 for the extremes..) is, that the ratio of Lift/Weight has to be the same.

BUT: as a P-47 weights as much as multiple Ki-43s, it has to produce multiple times the lift force, in order to get the same Lift/Weight ratio (=Gs) at the same speed.

That means, the '47 produces WAY more drag (more lift translates into more induced drag) at the same Gs, and it can only produce the same Lift/Weight ratio at higher speeds. Not considering the Ki's control-surface lock-up, this leads to a larger maneuvering envelope of the Ki (it can pull the same amount of Gs at much lower speeds due to the lower weight value).

Therefore, we have a relation between wingload and availiable G (again: you can not easily translate wingload into G-performance; you have to know lift-curves and AoA values for DIFFERENT AIRCRAFT, but you can draw conclusions for two a/c of the same type).

The problem of wingload is, it doesn't take critical AoA and lift-values into consideration.
You can built an a/c with a wingload close to zero, but terrible lift-coefficients.
the agin you can build an aircraft with high wingload, but high lift-coeficients.

JG14_Josf
03-22-2008, 10:34 AM
"the Fw190 could outturn the Me109 at any speed"

Anyone,

If turn performance is tested and recorded accurately the truth of the statement above can be proven or disproved.

To suggest that the person speaking did not test and record turn performance accurately is odd from my viewpoint since the person speaking actually flew the planes; I did not.

If the person suggesting that the person speaking is not accurate in his report of relative turn performance it seems possible that some form of proof could be presented in the effort to expose the error.

Suppose, for example, the person speaking was speaking about corner velocity turn performance and the person speaking was not speaking about sustained level turn performance.

Suppose the person speaking flew enough hours in both planes to arrive at his conclusion and suppose the conclusion, again, did not concern level turn performance so much as the conclusion was in reference to turn at or near corner speed where the plane is generating high g forces rather than the lower g forces that are possible when maintaining altitude in a level turn such as the type of turning that is typical when stall fighting.

Does the person reading my comments acknowledge the difference between slow speed (stall fighting) level, or horizontal turn performance and corner speed turn performance at high speed and high g?

A. Stall fighting, slow speed, low g, altitude gaining or altitude maintaining turn performance
B. Corner speed, high speed, high g, energy fighting, turn performance such as the turn performance recorded on the accelerated stall line on an EM chart

If the person reading my comments were to acknowledge how there are two separate and distinct turn performances (A and B above) the confusion about the comment by the combat pilot may be less confusing.

Suppose, again, that the pilot comparing how the 109 turns to how the 190 turns was comparing the high g turn performance or accelerated stall performance because that is more important to that pilot than the slow speed altitude gaining or altitude sustaining low g turn performance.

Suppose the person saying that the 190 could out turn the 109 at any speed was saying that at any high speed the 190 could generate more g force quicker.

If that were true, and I am not saying it is true, I did not fly those planes, but if that were true and that person was asked to clarify his statement the result could be a learning process rather than an assuming process whereby the assumption is an automatic assumption of error on the part of the person who actually flew the planes in actual combat.

It could be possible to ask, for example, the following question:

When you say that the 190 can out turn the 109 at any speed do you mean that a 190 can maintain a slower speed at a higher g while maintaining or gaining altitude; in other words do you mean that a 190 has a faster turn rate and a slower turn radius during a level turn at the slowest possible speed?

The person who made the comment might listen to that question and say something like this: No, the 109 was able to maintain a slower speed in a level turn but who would fight like that in combat? That would be suicide. In combat the idea was to maintain maneuvering speed at all times and thereby maintain an aggressive capability during combat. The 190 could maintain a higher speed and out turn the 109 easily during combat. The pilot merely thought about turning the 190 and the 190 was already threatening to black out the pilot. Of course that could not be maintained for very long in level or climbing flight. That is why fighting developed into a vertical fight after WWI.

I am not saying that that person would answer that question in that way. I am saying that the person may not be reporting error with his comment so much as the reader is reading error into the comment. Few pilots in WWII comment on the lack of agility for the 190, rather, the 190 is famous for being an agile aircraft and that agility may be what inspired the comment by that pilot in that video.

The 190 may have been able to out-turn (at corner speed) the 109 at any ˜high' starting speed in combat.

To suggest that the statement must mean exactly what the reader thinks the statement must mean is assuming that the reader can read the mind of the speaker.

Suppose, for example, an F-86 pilot were to say that the F-86 has a turn advantage over the Mig-15.

Like this:


Mahurin: It depends on the circumstances of the combat. On several occasions, I dogfought, like World War I, with a MiG. Once we started fighting about 37,000 feet, went around and around down to the ground and back up to about 26,000, before I shot him down. So that hadn't changed much since World Wars One and Two. It was very exciting and a lot of fun. On a couple of other occasions, we caught them when they didn't know we were there. That was just a matter of going in and shooting down an unaware pilot. But we could outperform them with the F-86's slab tail, we could turn faster than they could, we could dive faster, and we could pull out quicker. We didn't try to climb with them, because they could climb higher than we could. We tried to keep the combat on those elements where we had an advantage. Whenever they were gaining an advantage, we could always leave, we could always turn around and dive away.

Taken out of context you can get this:


we could turn faster than they could

There it is.

The F-86 can turn faster than the Mig-15

Now you know the facts.

Was that slow speed turn performance?

Was that slow speed and high speed turn performance?

Was that slow speed, altitude sustaining, turn performance only?

Was that high speed, corner speed, accelerated stall turn performance?

Here is where a test flight and data plotting comes in handy.

http://mysite.verizon.net/res0l0yx/IL2Flugbuch/Corner%20time.jpg

The test flight and data recording done by Chuck Yeager and John Boyd on a captured Mig-15 show the F-86 having a high speed, accelerated stall, corner speed turn advantage.

The absolute fastest turn rate and smallest turn radius possible (under high g load) goes to the F-86. That shows up on the historical record. There is little cause in claiming otherwise. The data proves the facts out for those planes at that altitude. If more of the same data can be uncovered it would be possible to confirm more of the pilot anecdotes.

Not having turn performance data does not disprove the pilot anecdotes.

When the pilot claims that the 190 could out-turn the 109 at any speed the claim may be misunderstood to mean something that was not meant in context.

When, for example, the F-86 pilots says that the F-86 can turn faster than the Mig-15 the claim may have nothing to do with sustained level flight or climbing flight turn performance at minimum speed.

Again the charts show how the actual performance plots out in actual flight.


http://mysite.verizon.net/res0l0yx/IL2Flugbuch/Wing%20Loading.jpg

It can be confirmed by those data plots that the Mig-15 can sustain a tighter turn in level flight compared to the F-86. That is not the same thing as saying the Mig-15 can turn faster. The data proves how the F-86 can turn faster on the accelerated stall line. If, for example, the two planes were dropping through that altitude (the chart is altitude specific) in a nose low turn at corner speed the F-86 would be turning faster since it has a lower corner speed and therefore a corner speed turn advantage at that altitude.

Since the chart is only good for that altitude tested and plotted on that chart it can't be assumed that the corner speed advantage would carry down or up into other altitudes.

Again the pilot anecdotes help in figuring out how these planes stacked up in reality.


The MiG pilot fired several rounds, and my wingman broke without telling me. I couldn't believe what I was seeing. Now the first two MiGs are coming around to cut off my wingman. I checked my fuel gauge and said to myself, "Oh man, this is one thing I don't need." I came back down, sandwiching the two MiGs between my wingman and myself. I could see the number three and four MiGs trying to cut me off, trying to come in behind me. This fight had started about 23,000 feet; we still had lots of altitude. I told him, "Put your nose down and keep four "G's" on that thing and we'll be okay. So he did, he was pulling it around and going down, the MiGs were trying to get on him, and finally I got in position on the number two man, and I hit him. Sparks flew and pieces of his tail came off. He broke off right away, then the leader broke off, and the two of them left. I called my wingman and said, "Okay, you're clear, roll it out, heading such and such and keep going. Climb to 32,000 feet and you'll be okay." He did that and got home fine.

Suppose the new game has a Mig-15 and an F-86 and in the game the F-86 is modeled with a high speed turn performance disadvantage. That would make the game wrong not the pilot wrong when the pilot says that the F-86 turns faster.

If the game models the F-86 with a corner speed advantage at that altitude for the chart for the F-86 tested in the chart and the Mig-15 in the chart the game will be accurate for that chart and the game could also model the Mig-15 with a slow speed, sustained altitude, or level turn advantage just like the chart shows.

Robert Shaw describes that type of difference as a single superior advantage rather than a double inferior disadvantage – or so my interpretation of Shaw's Angles/Energy fighting advantage differences suggest.

If the game models the F-86 and the Mig-15 with the turn performances plotted on that chart the combat between those two planes will tend to mirror the combat described in the pilot anecdotes. If, on the other hand, the Mig-15 has both the high and the low speed advantages (high g on the accelerated stall line and low g during altitude maintaining and altitude gaining turns at low g and low speed) if the Mig-15 is modeled double superior (unlike the chart data) the fight will not mirror the anecdotal evidence. A double inferior modeled F-86 would be effective only as a hit and run plane and would be a poor energy fighter without its historical corner speed advantage.

So...just saying that the German pilot is wrong because the game models things a certain way may be assuming to much about unknown variables; the 190 was said to be very maneuverable by more than one person. If the person does not understand what ˜very maneuverable' actually means the person may assume that the combat pilot is wrong when he says that the 190 could out-turn the 109 at any speed.

It may be a good idea to seek more accurate information before jumping to the wrong conclusion concerning things said by combat pilots who have actual experience in the actual planes during the actual war.

FatCat_99
03-22-2008, 11:31 AM
Originally posted by Kettenhunde:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> keeping same radius and flying faster through the turn

Velocity and radius are linked. Least that is what I was taught in all the Aerodynamic and Aircraft performance classes I took for my degree. How are we going to increase our airplanes velocity without affecting the radius?

Our aircraft's design particulars determine the sustainable angle of bank. However we can easily do a quick parametric study to determine the effects of increasing our velocity.

Two aircraft traveling at 200Kts make a 65 degree bank.

Radius of turn:

R = Vk^2 / (11.26 * tanAoB)

200^2 / 11.26 * 65 = 1656.5 ft

1656.5 ft radius

Rate of Turn

(1091 * tan 65) / 200 = 11.7 deg/sec

30 seconds to complete a 360 degree turn.

210^2 / (11.26 * tan 65)

Radius = 1826 ft

A 170 ft increase in radius!!!

Well he is not going to outturn anything by increasing his speed!

Let's see the effect on Rate of turn. That increase in speed should help somewhat.

(1091 * tan 65) / 210 = 11.14deg/sec

32 seconds to complete a 360 degree turn.

Well that did not work either. We have increased our rate of turn not decreased it and are going through our circle at .56 degrees a second less than before! Not really going to be noticeable but with that increase in radius, we are not going to be really outturning anything that could match the original parameters.

The airplane with slower stall speed generally speaking must go slower if he is to outturn his opponent. He must bring the fight down to the vicinity of the less capable at sustained turn performance aircrafts stall speed before any real turn advantage is realized.

Since we know that velocity is the key to zoom climb performance, the moment one opponent begins to be outturned, he can zoom above his opponent. This works in general for all aircraft. If he has not given up altitude, then he will be above his better turning opponent.

Studying these pages might help to shed some insight!


http://selair.selkirk.bc.ca/aerodynamics1/Lift/Page13.html


Keep in mind that the radius of turn equation is universal, therefore this graph is valid for any airplane, from a C-150 to a Boeing 747.

http://selair.selkirk.bc.ca/aerodynamics1/Lift/Min_Radius.html

</div></BLOCKQUOTE>

All of the above is true but you are completely missing the point here. You are fixated at bank and forgetting that better turning plane can maintain higher bank at same speed than worser turning plane.

That's how better turning plane can out turn the opponent. If we take example where worser turning plane is making maximum turn at 200 mph than it's Ps is 0, at same part of flight envelope better turning plane will have positive Ps.

That's surplus in Ps is than transformed in angles. You have 4 possibilities than in better turning plane.

1. Throttle down and maintain position

2. Make climbing turn and maintain horizontal separation but increasing alt and E advantage.

3. Maintain same radius which will result in higher bank and speed

4. Keep speed which will result in increased bank and smaller radius.

All of this can be easily seen on EM chart.
http://img201.imagevenue.com/loc360/th_05614_Turning_122_360lo.jpg (http://img201.imagevenue.com/img.php?image=05614_Turning_122_360lo.jpg)

FC

Kettenhunde
03-22-2008, 08:03 PM
All of the above is true but you are completely missing the point here. You are fixated at bank and forgetting that better turning plane can maintain higher bank at same speed than worser turning plane.

Hi Fatcat,

I don't believe I missed the point. In fact I point that out.


<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">keep speed and fly tighter

I know what you meant FatCat. This is the scenario the better turning aircraft can do. He is keeping his velocity but can choose from a higher angle of bank. This will result in in him outturning the other plane.

He is not increasing his velocity if he wants to outturn his opponent. So there is not "two" things the aircraft with better sustained turn performance can do, there is only one!

However the range of angles of bank that this superiority is exhibited is a very small portion of the envelope. Until the dirt barrier is reached, the other aircraft can still gain angles if he wishes.

The largest influence on turn performance is going to be the aircraft velocity. Generally speaking, the superior turning aircraft is the slower velocity aircraft.

All the best,

Crumpp </div></BLOCKQUOTE>


That's surplus in Ps is than transformed in angles. You have 4 possibilities than in better turning plane.


Your idea is correct but I think your have a misconception on the scale of that excess power.

Let's answer the question:

If we are making a maximum performance sustained turn, where is all this surplus PS?

If we are making less than a maximum performance sustained turn, are you aware of how much power is needed to effect performance? I think your having a problem of scale here. Your concept is correct however there simply is not that much power available to do much of anything that will make a difference in the air. Remember, our performance differences have to be rather dramatic to even be noticeable.

We need a large amount of excess power. I doubt any WWII fighter has that much excess PS and still can outturn another aircraft.

This isn't thrust either! This is power that we still have to convert to thrust.

Now let's make a quick SWAG of a Spitfire Mk IX Merlin 66 (+18) vs. FW190A8. Not to argue about specific numbers but let's just look at the excess power available at the Spitfire's maximum sustainable load factor.

It's not the numbers we care about, it is the performance trend.

The Spitfire can sustain ~3.65G's using all 1402.5 THP available.

The FW190A8 using all of its available 1683 THP can sustain about 3.27G's.

This leaves us a total of a .38G sustained turn advantage for the Spitfire.

To SWAG our Pr difference for the Spitfire:

D2/D1 = W2/W1

D2/1402.5 = (7500 * 3.27)/(7500 * 3.65)
D2 = {(7500 * 3.27)/(7500 * 3.65)} * 1402.5
D2 = 1256 THP

1402.5 - 1256 = 146.6 THP

That is a whooping 244lbs of excess thrust at the Spitfires best sustained turn performance velocity of 195KEAS.

Our ROC if we decide to "climb away" in our turn is going to be:

sin y = 244lbs/(7,500* 3.27) = .0099

ROC = 101.3 * 195KEAS * sin y

ROC = 196.5 fpm or 3.27 fps. In a 10 second period, our Spitfire would be 30 feet above it's starting altitude.

In short there is not anything really useful the Spitfire can do such a tiny bit of excess power.

Now compare that with a 9800lbs aircraft pointing its vector of lift just 5 degree's below the horizon produces ~512THP or 854lbs of thrust!

That is a ~589 SHP increase to our excess power. Of course we have lost ~200 feet in 10 seconds of flight but our velocity gain can make that back up.

All the best,

Crumpp

JG14_Josf
03-23-2008, 12:05 AM
If we are making less than a maximum performance sustained turn, are you aware of how much power is needed to effect performance?

Anyone,

Chances are the words used in the above sentence refer to a level turn where altitude is maintained at a steady g load and a steady or constant speed, bank angle, and angle of attack. Such a turn is not a maximum performance turn since a maximum performance turn is accomplished at the maximum possible g load at the lowest possible speed or corner velocity.

On an EM chart, such as those charts made by John Boyd, the sustained turn is plotted on the sustained turn stall line where, for example, the Mig-15 holds the sustained turn advantage. Someone might say: The Mig-15 turns faster than the F-86 and the actual meaning of that statement is much like the quote above where ˜maximum performance' can be misleading when that involves a requirement to sustain altitude, sustain bank angle, sustain angle of attack, sustain g load, and sustain airspeed (true).

The maximum sustained level performance turn may be only a fraction of the maximum performance turn at corner speed when measuring g load, turn rate, and turn radius.

The EM charts bears this out as the F-86 maximizes a higher g load, at a lower speed, with a faster turn rate, and a smaller turn radius well in excess of the Mig-15s maximum performance sustained turn.

The copy of the chart is not easily read with precision however the turn rate for the F-86 turning at corner speed is nearing 25 degrees per second while the Mig-15 at its best sustained turn rate is merely 18 degrees per second. One can hardly claim that the Mig-15 has a better turn rate than the F-86 when comparing maximum performance during a turn.

Similarly the F-86 is able to turn a smaller turn radius while turning at corner speed while the Mig-15 turns a much larger turn radius in a sustained turn where all the variables are held constant.

Even if the Mig-15 is maximizing turn performance at corner speed the F-86 corner speed is better by nearly 2 degrees per second.

I think that discriminating between maximum performance turns at corner speed and sustained turn performance turns can expose much of the confusion where combat pilots intend to describe relative performance. The description of relative turn performance spoken of by combat pilots may not be limited to lesser performing sustained level turn performance and the description of relative turn performance spoken of by combat pilots may actually be maximum turn performance at corner speed.

One would have to ask the combat pilot who speaks as to the indented meaning of his word choices. When someone says plane X turns faster than plane Y the person may be speaking about corner speed rather than sustained turn performance.



If we are making less than a maximum performance sustained turn, are you aware of how much power is needed to effect performance?

My guess is that the above describes the lesser performing turn performance.

Kettenhunde
03-23-2008, 02:31 PM
Hi Fatcat,

Let's examine your other three points specifically in light of what we have learned about our ability to "climb away" with that excess power. Maybe you will see that all of these are really just the same thing.

Our only real choice is to increase our angle of bank over a narrow range at the same velocity or reduce velocity even further. This is exactly why angle fights tend to get "low and slow".


FAtcat says:
Maintain same radius which will result in higher bank and speed

I have shown you that it is not possible to maintain the same radius and increase our velocity with our parametric study.

If you mean increase our rate of turn by increasing our bank angle, you are correct. Rate of turn and airspeed are not the same thing.

The aircraft is still traveling at the same airspeed. It does reduce the drag as a side effect of load factor reduction but as has already been demonstrated the performance gains are not easily exploitable in a dogfight. WWII fighters simply do not exhibit enough of a performance difference for this to come into effect.

This scenario still applies:


Crumpp says:

However the range of angles of bank that this superiority is exhibited is a very small portion of the envelope. Until the dirt barrier is reached, the other aircraft can still gain angles if he wishes.


Fatcat says:

Keep speed which will result in increased bank and smaller radius.

Not sure what you are trying to say here with this one. If you mean he can maintain his original turn superiority using all of the excess power, then you are correct.

An aircraft with sustained turning superiority only has a finite number of bank angles to choose from. Once he matches his opponent's bank angle then he will turn exactly the same and will not exhibit any superiority.

He cannot keep speed and turn at a smaller radius than his opponent at the same angle of bank. At the same angle of bank and velocity, all aircraft make exactly the same turn.


Fatcat says:
Throttle down and maintain position

We have already talked about the amount of excess power. This one should be pretty obvious.

I am sure you understand that if we are making a maximum performance sustained turn, we have no excess power. The only excess power our aircraft has is the difference between our aircraft's maximum and the opponent's maximum.

It takes a very large difference to become a noticeable advantage in combat. He could throttle down that 10% and match.

However if his opponent has a more agile aircraft, then he is begging for that opponent to roll his vector of lift below the horizon, convert weight to a useful component of thrust, gain angles, and roll back to gun solution! If that works at the superiority turning aircraft's maximum angle of bank, then will work even better at a reduced angle of bank!

So we can see that the philosophy followed by such design firms as Grumman, Republic, Vought, Mtt, and Focke Wulf was very effective basic formulation for a fighter aircraft. Otherwise, everyone would have just made bigger wings for their designs!

All the best,

Crumpp

gkll
03-23-2008, 11:30 PM
Originally posted by JG14_Josf:
.........

So...just saying that the German pilot is wrong because the game models things a certain way may be assuming to much about unknown variables; the 190 was said to be very maneuverable by more than one person. If the person does not understand what ˜very maneuverable' actually means the person may assume that the combat pilot is wrong when he says that the 190 could out-turn the 109 at any speed.

It may be a good idea to seek more accurate information before jumping to the wrong conclusion concerning things said by combat pilots who have actual experience in the actual planes during the actual war.

Mig IS double superior, with however a bunch of options foreclosed by bad handling at the limit, ie unrecoverable stalls (as per Yeagers autobiography) suggest perhaps some inherent instability which pushes the accelerated stall line to the right. However this is no analogy for 109s against 190s. The Mig had <problems>, that stall line <should be> pretty close to the 86, that would be typical, except the Russkies screwed up in the 'on the limit' handling, oops.

109s wont have accelerated stall lines offset to the 190 like Boyd and Yeager found for the 86 to Mig. So I dont agree your analogy to the thread subject.

Gday all

Xiolablu3
03-23-2008, 11:40 PM
Guys, guys, it wasnt the German pilot who said that, it was the ENglish Narrator who has probably never flown a Fw190 or a Bf109 in his life.

gkll
03-23-2008, 11:49 PM
Originally posted by Kettenhunde:
So we can see that the philosophy followed by such design firms as Grumman, Republic, Vought, Mtt, and Focke Wulf was very effective basic formulation for a fighter aircraft. Otherwise, everyone would have just made bigger wings for their designs!

All the best,

Crumpp

Perhaps modern day fighters have such enormous power available that they can afford to drag around big wings.... I note that after some ugly experience with 'poor turning' aircraft such as phantoms, 105s etc against Migs, the Americans never again bothered making a fighter that didn't turn as well as possible. F16s, Eagles Hornets Eurofighters all are more like a spitfire than they are a 190 in that sense. Not sure the Brits ever did go the 'brick with wings and a huge motor' as the Yanks did though, the Lightning turned very well for the time, not like a 104 at all for eg.

Scale changes everything though, with less power the drag from a bigger wing must have been a relative larger change, ie what would you gain from a Falcon with a (say) 1/3 smaller wing and a little less drag? On a P47 you could prob tell easy? The Japanese made quite a number of fighters initially with 2 or 3 sizes of wings, they must have seen large enough differences and they didn't always pick the biggest wing either.

When the 109 is turning against the 190 the difference shows up if the fight last more than a turn... the 109 with better power loading and wingloading will retain speed, so while you have the 190 slicing, the 109 may <already be> engaged in repositioning, in lag... with an alt advantage and the same speed. You say there is nothing in it <except> at low speed, however alt and speed count eh?

The way we fly is totally modern BFM and any advantage can be used. In our world the planes could be modelled just right and we could exploit your calc advantage, it shows up as our fabled 'e-retention'. RL no, not in WW2 anyways.

Kettenhunde
03-24-2008, 05:34 AM
All this is way off subject so let's not drag the thread. Let's start another thread if you want to discuss modern aircraft development after this reply. If you start the thread, I will move there to discuss it. Perhaps a moderator will be nice enough to just move both of our postings.


I note that after some ugly experience with 'poor turning' aircraft such as phantoms,

The F4 Phantom has to be considered one of the most successful designs in History.

The "ugly" experience you refer too has nothing to do with aircraft performance. It was a complete lack of pilot training in Air to Air combat due to the fact air to air combat was seen as obsolete with the advent of missiles. The first few F4's did not have even mount a gun.

That was a serious design flaw in a fighter and combined with an untrained pilot makes for a disaster.


The poor kill ratio also led the navy to establish its Fighter Weapons School, afterwards to become famous as Top Gun, which improved the ratio to 13 to1 and later to 22 to 1.

http://www.richard-seaman.com/Aircraft/Misc/F4dAirToAir/index.html

In Israeli service:

http://www.geocities.com/capecanaveral/hangar/2848/phantom.htm


With the upgrades already performed and those under contract, the F-4 Phantom II will probably still be flying in 2015 -- nearly 60 years after its first flight.

http://www.boeing.com/history/mdc/phantomII.htm


105s etc against Migs

The F-105 was designed as a Nuclear Strike Aircraft. It was designated a fighter only because it could carry air to air missiles. Remember, the thinking at that time was that dog fighting was over.


Republic Aircraft began work as a company venture on a new high-performance, single-seat low-level nuclear strike aircraft. The new aircraft, which was given the company designation of "AP-63", where "AP" stood for "Advanced Project", was to replace the Air Force's Republic F-84F Thunderstreak.

Many different design concepts were considered, gradually evolving towards something along the lines of a "stretched" F-84F with a bombbay for a nuclear weapon. The aircraft was to be fitted with an Allison J71 engine, though as it turned out, this powerplant would not prove powerful enough for the aircraft that finally flew and was never actually used.

The AP-63 would also be able to carry air-to-surface missiles (ASMs) and air-to-air missiles (AAMs) on underwing pylons. It was to have a top speed of Mach 1.5 and would be capable of defending itself against enemy fighters.

The F-105 was never conceived as an air superiority fighter.

http://www.faqs.org/docs/air/avf105.html


F16s, Eagles Hornets

I think you need to do some more research on this. IIRC, Boyd had some issue with the F-18 and F-16.

You are correct thought that thrust vectoring, high thrust engines, and other technology have combined to that modern fighters can push the envelope much farther than designers in the past.

However, your basic premise of designers seeking fighters with the best sustained turn characteristics is wrong.

All the Best,

Crumpp

Kettenhunde
03-24-2008, 05:38 AM
Guys, guys, it wasnt the German pilot who said that, it was the ENglish Narrator who has probably never flown a Fw190 or a Bf109 in his life.


That is a known fact, Xio. The discussion is the science of how aircraft turn which demonstrates why sustained level turn performance is not viewed as a primary characteristic in a fighter.

Mainly because of the fact all aircraft at the same angle of bank and velocity will make the same turn!

All the best,

Crumpp

JG14_Josf
03-24-2008, 11:32 AM
Mig IS double superior, with however a bunch of options foreclosed by bad handling at the limit, ie unrecoverable stalls (as per Yeagers autobiography) suggest perhaps some inherent instability which pushes the accelerated stall line to the right. However this is no analogy for 109s against 190s. The Mig had <problems>, that stall line <should be> pretty close to the 86, that would be typical, except the Russkies screwed up in the 'on the limit' handling, oops.

109s wont have accelerated stall lines offset to the 190 like Boyd and Yeager found for the 86 to Mig. So I dont agree your analogy to the thread subject.

Gkll,

The F-86 plotted against the Mig-15 on the EM chart shows a corner speed advantage for the F-86 against the Mig-15.

I want to make that clear first.

F-86 has a faster turn rate, greater g production, smaller turn radius, at a slower speed than the Mig-15 according to the plotted data on the chart.

You claim that the Mig-15 is double superior.

The Chart shows how the F-86 pulls more g force at slower speeds.

That is very clearly the way reality is right now. The EM chart exists for those two planes. There is no EM chart for the 109 versus the 190.

One more time: The EM Chart for the F-86 plots as lower corner speed at higher g, faster turn rate, and smaller turn radius and you claim that the Mig-15 is double superior.

You claim that the F-86 versus Mig-15 chart does not agree with ˜my' analogy concerning the relative difference in performance between the 109 and 190.

Here is my problem with that claim. What do you think is ˜my analogy?

How about this:

Do you think that the 190 corner speed was higher g or lower g than the 109?

Do you think that the 190 corner speed was a higher g at a lower speed than the 109?

I ask because I don't know the answer since no documentation has managed to record an accurate answer for any 190 compared to any 109 for corner speeds.

Why are you claiming to know what ˜my analogy' is or is not? Why not ask?

Shaw describes specific, rather than vague, performance characteristics leading to a determination of single or double superiority and Shaw also describes the tactics that work for planes having a single superiority advantage against a single inferior opponent.

Typical of a single superior plane is the use of nose to tail geometry and vertical maneuvering like the dive to extend, pull out, and pitch back after a nose to tail turn.

Are you saying that the F-86 with the lower corner speed in the EM chart would not hold an advantage when using nose to tail geometry and vertical maneuvering over a Mig-15 if both planes performed according to the EM chart (rather than performance opposite to the EM chart)?

I am curious as to your claim of double superiority and what information you use to base that claim.

As to the 190 and 109 I can't offer any EM charts where corner speed is accurately measured against sustained turn performance. Many people have written comments on the differences in performance but there are no numbers recorded for corner speeds; as far as I know.


Mig IS double superior, with however a bunch of options foreclosed by bad handling at the limit, ie unrecoverable stalls (as per Yeagers autobiography) suggest perhaps some inherent instability which pushes the accelerated stall line to the right. However this is no analogy for 109s against 190s. The Mig had <problems>, that stall line <should be> pretty close to the 86, that would be typical, except the Russkies screwed up in the 'on the limit' handling, oops.

109s wont have accelerated stall lines offset to the 190 like Boyd and Yeager found for the 86 to Mig. So I dont agree your analogy to the thread subject.

We seem to be talking about two different things and I have no idea what inspires you to claim that the Mig-15 stall line should be this or that since the chart records where the stall line is relative to the F-86 for those two planes at that altitude. More data is better.

If you have data and can post data recording the accelerated stall lines for any WWII plane please do so and back up your opinion concerning what those accelerated stall lines are.

Again – data is better.

gkll
03-25-2008, 12:02 PM
Originally posted by JG14_Josf:


Are you saying that the F-86 with the lower corner speed in the EM chart would not hold an advantage when using nose to tail geometry and vertical maneuvering over a Mig-15 if both planes performed according to the EM chart (rather than performance opposite to the EM chart)?

.....

I am curious as to your claim of double superiority and what information you use to base that claim.


.

If we assume the chart is correct (I did) then the 86 will 'outturn' the Mig, <when high energy>. Say they merge coe nose to nose. Looking at the chart the 86 has some time to capitalize on the poor handling of the Mig. However if a kill or kill position is not achieved within (say) a turn or two, once the 86 has bled down the Mig holds all the cards. The Mig either ends up at the same speed but higher, at a higher speed and co-alt, and at that point with higher thrust/weight and less e-bleed from manuevering, can dominate the fight. The 86 will have to dive away or die.

No I don't know what the accelerated stall line looks like for the 109 and 190, however 109s only run into handling problems at high speeds (apparently) due to stiff elevators. Its stall line should probably be to the left of the 190 slightly. Migs on the other hand did have 'on the limit' handling problems and it is my supposition that this is why the accelerated stall line is to the right, normally the stall line would be similar or advantageous to the lighter wing loaded fighter. However I guess the Mig designers screwed up, this would not be the typical would it? ie a fighter with power and wing loading advantage having a stall line offset to the right?

gkll
03-25-2008, 12:21 PM
Originally posted by Kettenhunde:
All this is way off subject so let's not drag the thread. Let's start another thread if you want to discuss modern aircraft development after this reply. If you start the thread, I will move there to discuss it. Perhaps a moderator will be nice enough to just move both of our postings.

However, your basic premise of designers seeking fighters with the best sustained turn characteristics is wrong.

All the Best,

Crumpp

Teh second half of my post tried to tie the new fighter stuff to 109s and 190s, not so off topic?

My post is being taken too literally. You had posted something to the effect that the heavy fighter concept via Grumman etc was the way forward. I was just pointing out that after the generation of fighters such as Phantoms, 105s 104s, which are not really 'turn' fighters, the US went back to a balance of capabilities. Next gen fighters are perhaps even more maneuverable yet, ie eurofighter. It (turn capability) went from being 'unimportant' to 'important', as they realized 'dogfighting' was still a possibility and had to be designed for. That was all I was trying to say, plus that with modern powerplants you don't have to make as many compromises as in ww2.

Kettenhunde
03-25-2008, 07:18 PM
You had posted something to the effect that the heavy fighter concept via Grumman etc was the way forward. I was just pointing out that after the generation of fighters such as Phantoms, 105s 104s, which are not really 'turn' fighters, the US went back to a balance of capabilities.

I think you have read too much into my posting. A balance of capability has always been the goal for fighter design. I pointed out that firms such as Grumman understood this and did not seek sustained level turn ability as a primary performance characteristic. Sustained turning ability as a primary characteristic has not been a design goal since WWI. It has only recently returned to favor with designer due to technological advancements.

This is due to some sound scientific reasoning on the nature of how aircraft turn performance works.


Next gen fighters are perhaps even more maneuverable yet, ie eurofighter.

Certainly, Power available to power required is the fundamental relationship of turning performance.

Technological advancements such as thrust vectoring have opened up possibilities that did not exist a few years ago.

However this technology allows aircraft to enter the realm of "super maneuverability" which is on a whole different level from a conventional aircraft.

Turning has become more important only due to super maneuverability. Super maneuverability is only possible through these advancements in technology.

The only counter to aircraft with this technology is another aircraft with the same technology.

No comparison exists to aircraft lacking this technology.

All the best,

Crumpp

gkll
03-25-2008, 11:25 PM
Originally posted by Kettenhunde:

....

Turning has become more important only due to super maneuverability.


.....

All the best,

Crumpp

This is where I dont agree, turning got 'back on the table' with the Eagle and ilk, <compared to> the philosophy represented by Phantoms or 104s (and P47s? 190s?). Eagles turn good because the designers forsaw 'dogfights', 104s don't because their design teams didn't. Change in this 'balance of capabilities'.

But sure we largely agree. Let the thread get back to 109s?

Kettenhunde
03-26-2008, 02:45 AM
turning got 'back on the table' with the Eagle and ilk,

The Eagle is not a great sustained level turner.

It is highly maneuverable however.

Maneuverability and sustained level turn ability are not the same thing.

The FW-190 remember was rated by everyone who tested it as very maneuverable.

http://img264.imageshack.us/img264/5087/spitixsg1.jpg (http://imageshack.us)

http://img264.imageshack.us/img264/6066/spitvbnd8.jpg (http://imageshack.us)


All the best,

Crumpp

JG14_Josf
03-26-2008, 04:44 AM
If we assume the chart is correct (I did) then the 86 will 'outturn' the Mig, <when high energy>. Say they merge coe nose to nose. Looking at the chart the 86 has some time to capitalize on the poor handling of the Mig. However if a kill or kill position is not achieved within (say) a turn or two, once the 86 has bled down the Mig holds all the cards. The Mig either ends up at the same speed but higher, at a higher speed and co-alt, and at that point with higher thrust/weight and less e-bleed from manuevering, can dominate the fight. The 86 will have to dive away or die.

No I don't know what the accelerated stall line looks like for the 109 and 190, however 109s only run into handling problems at high speeds (apparently) due to stiff elevators. Its stall line should probably be to the left of the 190 slightly. Migs on the other hand did have 'on the limit' handling problems and it is my supposition that this is why the accelerated stall line is to the right, normally the stall line would be similar or advantageous to the lighter wing loaded fighter. However I guess the Mig designers screwed up, this would not be the typical would it? ie a fighter with power and wing loading advantage having a stall line offset to the right?

Gkll,

Thanks for the response. I'm going to respond as well as I can (limited, of course, by my ability to define the term ˜well').

If you are flying an F-86 and there is the slightest advantage in energy maneuverability it is suggested, by Shaw, to utilize a nose to tail turn since the nose to nose turn will favor the plane with the angles advantages. Why do you set up a nose to nose turn to prove the double superiority of the Mig-15? Do you assume that the F-86 is better at angles fighting the Mig-15?

When I read the reports on how the F-86 was used effectively in combat against the Mig-15 I read how energy tactics were used and that is where I find the data supporting the opinion that the F-86 was not double inferior to the Mig-15. More data is available from John Boyd as John Boyd describes ˜Fast Transients'.

The EM chart merely adds data to the pile in the effort to quantify performance. A sustained horizontal nose to nose fight or ˜stall fight' will certainly favor the Mig-15 based upon its superiority at turning a horizontal turn at slower speed, higher g, faster turn rate, and a smaller turn radius.


If we assume the chart is correct (I did) then the 86 will 'outturn' the Mig, <when high energy>. Say they merge coe nose to nose. Looking at the chart the 86 has some time to capitalize on the poor handling of the Mig.

Here is a good place to offer any data confirming or quantifying what you term as ˜poor handling'. If you have a means of transferring the data that quantifies poor handling then I can process that data too. According to the chart the Mig-15 will turn inside the F-86 in a level, sustaining altitude, turn. How poor is the Mig-15's handling?

If by poor you mean that the Mig-15 will stall when following the F-86 at corner speed, then I can see that on the chart. In order to get on the chart the plane has to be flying. The Mig-15 will stall where the F-86 keeps on flying. That is not ˜poor' – that is stalled. In between flying and stall is a region called ˜buffet' and an easy handling plane, if I understand this right, will buffet a lot before stalling. The stall will be easy to feel as the onset of the stall is buffeting. Is buffeting what you mean by ˜poor handling'?

If by ˜poor handling' you mean that the Mig-15 was prone to an abrupt stall, then that means the plane was flying right up to the stall efficiently – then it stalled abruptly. That would increase turn performance and decrease handling. If that was the case and now you are saying that the Mig-15 was not flown to the limit and that explains the accelerated stall line being less for the Mig-15 (because the pilot didn't fly the plane to the limit), then that would be more data to chew on.

I'm pretty sure that Chuck Yeager was capable of getting the plane flown to the limit. I could be wrong – of course. The pilot anecdotes confirm single superiority held by the F-86 as they use energy tactics against the Mig-15 and John Boyd describes the advantage in terms of "Fast Transients". This has to do with dynamic performance or agility. Shaw tends to communicate the energy fighting performance advantages in more obsolete terms like ˜sustained turn rate'. Actually; Shaw spells things out well and warns about an over reliance upon published numbers.


However if a kill or kill position is not achieved within (say) a turn or two, once the 86 has bled down the Mig holds all the cards. The Mig either ends up at the same speed but higher, at a higher speed and co-alt, and at that point with higher thrust/weight and less e-bleed from manuevering, can dominate the fight. The 86 will have to dive away or die.


If the F-86 pilot tries to gain advantage using angles or stall fighting tactics where the stick is continuously pulled and the nose is continuously held level or climbing, then the Mig-15 will surely gain angles in time. The chart certainly documents that fact.

The actual F-86 pilots went vertical. That is classic energy tactics described by Shaw. Pitch back, Sustained Turn Technique, Diving extensions, pull-outs, zoom climbs, and nose to tail geometry or Energy Tactics. Not angles tactics. Angles tactics favor the angles fighter (single superior) Mig-15.

Do you assume that the Mig-15 would gain more energy over the F-86 in vertical diving and vertical zooming and/or turns at high speed and/or turns during a hammerhead or pitch/back? If so then, why do you assume that to be true? Dive acceleration is not on the chart. Zoom climbing deceleration rate is not on the chart. The chart does have high speed turn performance but there isn't any way, not a way that I know, of quantifying the energy loss on the EM chart during a corner speed turn. That would show up as a dive angle as far as I can tell. And that EM chart is specific to an altitude – not a dive.


higher thrust/weight and less e-bleed from manuevering, can dominate the fight. The 86 will have to dive away or die.


The Mig-15 will "BLEED less E" in a sustained level turn according to the chart. At corner speed the dynamic changes and that may be due to your ˜poor handling' or it may be due to a huge increase in drag for the Mig-15 at high speed and high g. Drag BLEEDS E.

I think game players are infected with game performance and that infection causes error in accurately perceiving reality. To assume that all aircraft behave as a game behaves is hard to believe to me. The nature of the accelerated stall line, on the EM chart, for the real planes, is what it is and the F-86 has a steeper accelerated stall line. To say that any plane ˜should' have the same accelerated stall line and to say that the reason for the poor Mig-15 accelerated stall line is ˜poor handling' is saying something. What is ˜poor handling'?


The 86 will have to dive away or die.


In between the initial merge and diving away, if I have this right, an energy fighter has geometry, perhaps turn rate at high speed, dive acceleration, and zoom climb deceleration advantages to employ before having to dive away (and try again). The concept of ENERGY BLEED is a two way street. If you don't know this fact, then you may want to learn it. John Boyd calls it "Fast Transients" and the plane that can decelerate faster will perform a tighter "Natural Hook" turn because turn rate maximizes, and turn radius minimizes, at the highest g, and AT THE SLOWEST SPEED so taking too much time in the process of BURNING ENERGY in a turn will increase turn radius and decrease turn rate relative to the plane that can BURN ENERGY FASTER. That is assuming, of course, that the air mass being moved isn't being wasted, rather, the air being moved is being employed in the production of lift force. There is an assumption that all wings have the same L/D at all speed and all g loads and that would, if it could be true, plot out as the same accelerated stall line curve (moved left or right on an EM chart) as far as I can tell.



No I don't know what the accelerated stall line looks like for the 109 and 190, however 109s only run into handling problems at high speeds (apparently) due to stiff elevators

That is not true. That is a myth. The 109 was equipped with an adjustable horizontal stabilizer incidence angle so the pilot can trim elevator heaviness out of the controls. I am speaking about combat speeds. The Spitfire has the opposite problem. The pilots had to push the stick forward just to keep the plane from going up (pulling out of the dive) at high speed (above combat speeds) so the pilot had to trim nose low or push on the stick (according to what I've read). Combat Speeds, like corner speed, for Fighter Planes were speeds where control problems were not a problem. If they were then it, if I may offer my opinion, was not a fighter plane.

To assume what any two aircraft would plot for an accelerated stall line is one thing. Having a Chart that does plot the accelerated stall line is something else. How many game players will insist that the Mig-15 ˜should' have a lower corner velocity over the F-86? How many will insist that is ˜should' when the game models the Mig-15 with a lower corner speed than the F-86?


...normally the stall line would be similar or advantageous to the lighter wing loaded fighter. However I guess the Mig designers screwed up, this would not be the typical would it? ie a fighter with power and wing loading advantage having a stall line offset to the right?

Perhaps the efficiency of the wing, measurable as loaded lift over drag determines the shape of the accelerated stall line and wing loading and power loading (not vectored thrust) merely moves the accelerated stall line to a higher or lower speed (moved left or right on the chart).

Even so...that steepness or shallowness of the accelerated stall line does not directly measure ENERGY BLEED as far as I can tell so far. I think it may be worth considering since a less efficient wing would expend more energy moving air out of the way and less energy thrusting air opposite the lift vector as lift force.

People have this idea that the higher weight plane is the poor energy fighter. That is false.

gkll
03-26-2008, 11:25 PM
Originally posted by JG14_Josf:
Gkll,


The actual F-86 pilots went vertical. That is classic energy tactics described by Shaw. Pitch back, Sustained Turn Technique, Diving extensions, pull-outs, zoom climbs, and nose to tail geometry or Energy Tactics. Not angles tactics. Angles tactics favor the angles fighter (single superior) Mig-15.

Do you assume that the Mig-15 would gain more energy over the F-86 in vertical diving and vertical zooming and/or turns at high speed and/or turns during a hammerhead or pitch/back? plane is the poor energy fighter. That is false.

Yes I do assume this. Two reasons, neither directly on the chart. The Mig had lower wing loading and had higher power loading. It will pull less AOA (lower induced drag) and accelerate better, it has higher excess power at a turn and speed which would be typical in manuevers such as you describe. It will relentlessly gain energy on the Sabre. The Sabre has as its advantage the ability to run high g manuevers, it will bleed e rapidly for this reason (it can actually maneuver in that part of the envelope), and because of the lower power loading and higher induced drag. So whereas the Sabre would have no advantages in moderate 'vertical' maneuvering and plenty of disadvantages, it would have a big angles advantage as long as it held the e to operate out towards its stall line. Its interesting that the american pilots used vertical tactics against the Migs. BFM was in its early days?

By 'poor handling' I don't mean anything specific. It could be poor elevators, it could be (as you suggest near the end of your post) bad lift, which could invalidate what I say just above. It could even be Yeager not pushing the limit. It is documented he was warned not to spin, N Koreans lost many pilots that way. So spin testing was a no no.... this last seems as likely as anything, instability under high g leading to oscillating, pitching up and quick unrecoverable spins. This is how Yeager described the handling in the very test you are referring to

Nice chatting, atypically I largely agree with your post. I personally don't like high e-bleed, don't consider it an advantage as you do. You can always chop your motor or pop flaps if you need that effect....

EDIT< to be fair I am painting an 80% scenario Mig vs Sabre. 80% being the ~ amount of variation in combat capability, fighter vs fighter, explained by wingloading and powerloading. If the Mig suffers oscillation and pitchup leading to fatal spins then perhaps back in behind the stall line it is not doing so well for drag.... this is the 20% that can invalidate the 80.... however Yeager describes the handling as good under the limit so I guess not. >

gkll
03-26-2008, 11:44 PM
Originally posted by Kettenhunde:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">turning got 'back on the table' with the Eagle and ilk,

The Eagle is not a great sustained level turner.

It is highly maneuverable however.



All the best,

Crumpp </div></BLOCKQUOTE>

Hopefully you are speaking to a broader audience to some extent, or do you really see me as someone who doesn't understand 'sustained turn', BTW this comes from you in this thread, I never used the term once.... though you seem to want me to?

Eagles and their brethren 'turn' a ton better than 104s and theirs, and represent a shift in philosophy, this is fact. 'Dogfights' (whatever those are precisely... certainly angles fighting to some degree) were not considered in the relentless and single minded design of the 104. There was in fact a shift in thinking. Based on experience of jet combat. Turning got back on the table.

I am mindlessly repeating myself on this because you appear to disagree with the above? Or maybe you think I don't ahve a copy of Shaw, haven't looked on the net (plenty there) and don't 'get' maneuverability vs sustained turn?

Anyway over time I have learned a lot from your posts and continue to, no harm no foul.

Kettenhunde
03-27-2008, 02:22 AM
Turning got back on the table.

This is what I disagree with. Maneuverability got back on the design table, not turning. That is a fact.

The previous aircraft where designed in a time when the thinking was that dog fighting was dead due to missile technology.

The next generation was designed with the fact dog fighting was still a reality. In a dogfight you need maneuverability.

All the best,

Crumpp

JG4_Helofly
03-27-2008, 04:22 AM
Interesting discussion.

The more I read in here, the more I have the impression that the gaming world is not very close to RL.
In il2 there are 2 options: speed or turning. If you fly a fw 190 or a p 51, don't touch your ailerons or your elevator. If you fly a spit: stick back!
So what is the high manoeuvrability for, the 190 have? Even with the high roll rate I can't get away from a spit at high speed. I even prefer to simply push the stick full forward then rolling over and dive because the second manoeuvre takes longer. If you pull too hard you will loose very much speed and stall, if you are easy on the stick you are a nice slow moving target.


So the theorie of manoeuvrability for dogfight is interesting, but does not seem to work in this game IMO. If you don't have a big energy advantage in a fw 190 against a spit for exemple, you can start running for home.
This is my opinion after several years of playing this game. Manoeuvrability is nice if you are approaching at high speed and you have to correct your flight path for the shot. In such a case the 190 is better than the 109.


Now the question about manoeuvrability today whith modern jets. IMO it's very dangerouse to run away from an enemey if you are already close to him, because he could simply fire a medium range missile and it's game over for you. So if you can't hold your nose in his direction you will soon be dead. That's how I would explain it, but I am by far not an expert.

Just my 2 cents

Manu-6S
03-27-2008, 05:20 AM
http://forums.ubi.com/images/smilies/agreepost.gif

Waiting SoW...

JG53Frankyboy
03-27-2008, 06:18 AM
Originally posted by JG4_Helofly:
..................
Now the question about manoeuvrability today whith modern jets. IMO it's very dangerouse to run away from an enemey if you are already close to him, because he could simply fire a medium range missile and it's game over for you. So if you can't hold your nose in his direction you will soon be dead. That's how I would explain it, but I am by far not an expert.

Just my 2 cents

thats also my belive... the old tactic of the "canon"-times, where you dived ore climbed away, are with the very reliable air-to-air missiles over - you cant run away anymore. You HAVE to stay.

propably some modern fighterpilots here can make the things more clear.

Bremspropeller
03-27-2008, 10:03 AM
Zooming away neither is agood idea in the age of HMS and all-aspect T/V heaters.

"If looks could kill" definately has a different meaning today.

JG14_Josf
03-27-2008, 12:17 PM
The Mig had lower wing loading and had higher power loading. It will pull less AOA (lower induced drag) and accelerate better, it has higher excess power at a turn and speed which would be typical in manuevers such as you describe. It will relentlessly gain energy on the Sabre.

gkll,

I am at a loss as to why you fail to address my question while you think you have addressed my question.

Suppose we take a sentence out of your supposed answer and see if that answer has anything to do with my question?


It will pull less AOA (lower induced drag) and accelerate better, it has higher excess power at a turn and speed which would be typical in manuevers such as you describe.

Is the problem a failure to read the EM chart accurately?

The F-86 is flying at higher g and lower speed (lower corner velocity), so, how can your sentence (that supposedly answers my question) be true?

Your answer could answer a question asked about sustained turn performance. That was not my question.

How about taking my question apart into the components that appear to make a good energy fighter in practice (not necessarily what is supposed to happen based upon the estimated or calculated performance figures).

First let's look at maximum turn performance or corner velocity (and this could be done for any two planes that have an accurate record of corner velocity derived from flight tests such as The Wind Up Turn or Loaded Decelerations).

Which plane has a higher maximum turn rate, a lower minimum turn radius, and a therefore which plane has a high speed turn advantage (as opposed to a slow speed turn advantage or ˜sustained' turn advantage)?

I'll repeat my question in case I've forgotten what I did ask:


Do you assume that the Mig-15 would gain more energy over the F-86 in vertical diving and vertical zooming and/or turns at high speed and/or turns during a hammerhead or pitch/back? plane is the poor energy fighter. That is false.

"...turns at high speed...."

The F-86 wins. The F-86 keeps on turning while the Mig-15 is stalled.
Here is your answer again:


It will pull less AOA (lower induced drag) and accelerate better, it has higher excess power at a turn and speed which would be typical in manuevers such as you describe.

So...your answer fits if you answer a question asked about ˜sustained' turn performance. Your answer is false if your answer intended to answer my questions concerning high speed turn performance.

What about vertical dive acceleration? Which Jet wins that race?

Before looking into some of the available information it may help to begin constructing a scenario whereby a single inferior (energy superior) fighter will fight a single superior (angles fighter) in reality.

Suppose two planes were flying nose to nose and both planes were flying slowly (at or near cruise or some other word describing relatively slow flight). Both planes see each other and both planes dive for speed before turning at high speed.

Got that?

I'm not suggesting that the angles fighter would dive for speed in that situation. I am comparing specific performance advantages.

Both planes are slow. Both planes dive for speed. Both planes are setting up a turn at high speed. We already know that the F-86 will turn at higher g, higher turn rate, and smaller turn radius, at a slower speed (lower corner speed), so, the F-86 will reach corner speed at a lower speed and therefore the F-86 can dive for that speed to dive to his advantage over the Mig-15.

Which plane accelerates in a dive faster? How much of an advantage is the advantage if an advantage in dive acceleration exists?

Dive (http://migluver.wordpress.com/2007/10/08/f86-sabre/)


Mahurin: It depends on the circumstances of the combat. On several occasions, I dogfought, like World War I, with a MiG. Once we started fighting about 37,000 feet, went around and around down to the ground and back up to about 26,000, before I shot him down. So that hadn't changed much since World Wars One and Two. It was very exciting and a lot of fun. On a couple of other occasions, we caught them when they didn't know we were there. That was just a matter of going in and shooting down an unaware pilot. But we could outperform them with the F-86's slab tail, we could turn faster than they could, we could dive faster, and we could pull out quicker. We didn't try to climb with them, because they could climb higher than we could. We tried to keep the combat on those elements where we had an advantage. Whenever they were gaining an advantage, we could always leave, we could always turn around and dive away.

So...in the comparison so far the F-86 gains speed faster in a dive and it will therefore reach its lower corner velocity sooner as the F-86 and the Mig-15 see each other head-on and both begin to dive for maneuvering speed at corner velocity. Again – and of course – the angles fighter having a higher climb rate may do well to avoid fighting the energy fight, which was not my question.

One plane will accelerate faster with the nose down and I think the evidence presented (it may be wrong of course) is clearly showing which plane dove faster in reality.


Whenever they were gaining an advantage, we could always leave, we could always turn around and dive away.

My question was not: If both planes start turning sustained or climbing turns, if both planes tried to keep turning and climbing or turning and maintaining level flight, which plane would gain more energy?

Both planes dive and the F-86 dives faster. Does it gain total energy quicker or is the loss of altitude a net loss of energy despite the more rapid increase in speed? Perhaps Tagert can plot that on a chart – and it would be interesting.

My question concerned dive acceleration (F-86 is better), turns at high speed (F-86 is better), zoom climb deceleration, and slow speed (gravity assisted) reversal turn performance.

Here is where the data fails to answer my question. Suppose that the scenario were to occur in reality. The two pilots are flying slow and both pilots nose over to gain speed up to corner speed or as Shaw puts it "vertical maneuvering speed, whichever is higher" and by the available information the F-86 reaches that speed first. Now, suppose, the F-86 pilot uses the superior turn rate, superior g production at a slower speed to convert the superior rate of speed increase into a vertical, straight up, zoom climb.

Which plane stalls first? Does the plane that starts the turn sooner stall first (that would be the F-86)? Does the plane that starts the turn sooner from a higher speed stall first (that would be the F-86)? Does the plane that completes the turn from dive to zoom climb sooner stall first (that would be the F-86)?

Forget about dodging the question with a comment about why the Mig-15 pilot wouldn't play that game or would gain angles, eventually, by playing that game because the next example of ˜how to' use energy advantages with energy tactics is to employ nose to tail geometry with Shaw's Sustained Turn Technique. This initial question merely intends to identify which fighter plane gains in vertical maneuvering and high speed turns.

I think that few planes will have any significant advantage in rotating around during a slow speed gravity assisted turn at the top of a zoom climb unless the fighter plane is equipped with vectored thrust.

So...

Which plane dives faster?

F-86

Which plane turns faster at high speed?

F-86

Which plane rotates around with gravity assisted turns at the top of a zoom climb or slow speed hammerhead type wing-over turns?

No data

Which plane decelerates quicker or faster in a vertical zoom climb?

?

Here is where the answer can be dodged again just like the answer was already dodged. If the answer is to say that the Mig-15 will gain energy faster during climbing at best climb angle or even best climb speed, then the answer dodges the question.

Both planes dive.

The F-86 reaches a lower corner speed quicker and begins to maximum a turn from dive to vertical zoom climb. The F-86 will complete that turn sooner.

Now the F-86 starts going straight up sooner. The Mig-15 follows.

Now both planes are going straight up.

Which one decelerates and begins to rotate around into a hammer-head or wing-over sooner and which plane has gained more altitude?

If the assumption is such that the Mig-15 will "Bleed energy" slower and therefore the Mig-15 will stall last and stall at a higher altitude because of its higher power-loading and lower wing-loading, then why does that assumption ignore drag loading?

Putting aside the complete lack of actual data that can be used to answer the question accurately and even allowing for both planes to reach the vertical zoom climb attitude at the same time and at the same altitude the fact is that the F-86 will be at a higher energy state at the same altitude and at the same speed and therefore it will require more air resistance (drag) to slow the F-86 down. That is fact. The more massive F-86 will require more force to slow it down than the force required to slow down the less massive Mig-15 in a vertical zoom climb. That is fact. Both plane cannot accelerate going straight up. Both planes will stop accelerating (adding velocity) the moment they begin turning at the bottom of their dives (and the F-86 accelerates faster going down and the F-86 spends less time turning from down to up).

When both planes are pointed straight up there will be too much force resisting any acceleration so the one that decelerates faster will lose energy faster.

Again: to assume that the Mig-15 will not decelerate as fast as the F-86 going up is an assumption and that assumption really isn't any different than an assumption that predicts that the Mig-15 will accelerate faster than the F-86 in a dive.


Whenever they were gaining an advantage, we could always leave, we could always turn around and dive away.

That sounds a whole lot like the fighter pilots who comment on how much faster the Fw190 could dive away from the Spitfires and then how the P-47s could dive away from the Fw190s.

To assume, as the game models, that the lighter planes can accelerate faster going vertically down is to go against the actual data that exists. To go on and ignore the error of that assumption and then assume that the vertically up trajectory would also favor the lighter planes is, again, ignoring the available data as if the available data never existed.

Why be ignorant on purpose?

That is a serious question. If I ask, for example, which plane dives faster, then why not answer that question rather than ignore that question?

I can move onto the Sustained Turn Technique and nose to tail geometry next. I think it is worth discussing; I'd rather not ignore it.


The Mig had lower wing loading and had higher power loading. It will pull less AOA (lower induced drag) and accelerate better, it has higher excess power at a turn and speed which would be typical in manuevers such as you describe.

That is an error compounded upon an error. Again – the F-86 can keep on flying at a higher g load and a slower speed while the Mig-15 cannot (it stalls).

The Mig-15 stalls while the F-86 keeps on turning. That means the Mig-15 has to go past its maximum AOA to produce as much acceleration on the lift vector as the F-86 (despite the Mig-15s lower weight, lower wing-loading, and higher power-loading).

If the assumption is such that an advantage in maintaining and gaining altitude automatically becomes an advantage in dive acceleration, then I can see why the error is made.


Whenever they were gaining an advantage, we could always leave, we could always turn around and dive away.

Those are words written by someone who flew combat missions.


The Mig had lower wing loading and had higher power loading. It will pull less AOA (lower induced drag) and accelerate better, it has higher excess power at a turn and speed which would be typical in manuevers such as you describe.


It will pull less AOA (lower induced drag) and accelerate better, it has higher excess power at a turn and speed which would be typical in manuevers such as you describe.

Where did I describe maneuvering? If the F-86 has a lower corner speed it then has higher excess power at that speed, that g, and during that moment of dynamic flight – the Mig-15 stalls before reaching that g load at that speed.

Why ignore that fact?

Why ignore the evidence that records a dive acceleration advantage?

This is the same type of thing ignored when all the evidence proves how the Fw190A was superior in acceleration to the Spitfire V. The game models the opposite. Will the game model the Mig-15 with greater dive speed acceleration and a lower corner velocity than the F-86 and, of course, that will be ignored or defended as being accurate – because the Mig-15 has a lower wing-loading?

Ignoring drag-loading appears to be complete.


So whereas the Sabre would have no advantages in moderate 'vertical' maneuvering and plenty of disadvantages, it would have a big angles advantage as long as it held the e to operate out towards its stall line. Its interesting that the american pilots used vertical tactics against the Migs. BFM was in its early days?


What is ˜moderate vertical maneuvering'? What disadvantages are imagined when the F-86 is fighting moderate ˜vertical' maneuvering? Is this more of the same assumption concerning acceleration advantages that does not exist for the Mig-15 in a dive, AOA advantage that doesn't exist for the Mig-15 at the F-86 corner speed, and another assumption concerning vertical rates of deceleration that has no data to support the claim (drag-loading)?

Why be so authoritative about error?

Which plane accelerated faster in a dive?


Whenever they were gaining an advantage, we could always leave, we could always turn around and dive away.

That can be an error – of course. It seem clear enough to me. That is much like the claims made of how the Fw190A could accelerate better "under all conditions of flight" over the Spitfire V and how the P-47 performed vertically. One was better than the other rather than the opposite being modeled in the game.


It will pull less AOA (lower induced drag) and accelerate better, it has higher excess power at a turn and speed which would be typical in manuevers such as you describe.

The Mig-15 cannot ˜pull less AOA (lower induced drag) and accelerate better" at the F-86's corner speed. The EM chart clearly shows that the Mig-15 will stall before reaching the F-86 corner speed. That is what is recorded on the chart.

Why ignore the information that is recorded on the chart? Why confuse ˜high speed' or ˜corner speed' turn performance with ˜sustained' or ˜maintaining constant speed and altitude' turn performance?

Sure, the Mig-15 can maintain maximum AOA during a ˜sustained' turn. That was not the question.


This is how Yeager described the handling in the very test you are referring to


If you have a source of information concerning the above quote please reference that source.


Nice chatting, atypically I largely agree with your post. I personally don't like high e-bleed, don't consider it an advantage as you do. You can always chop your motor or pop flaps if you need that effect....

Here is a link to "Fast Transients" where John Boyd describes a "Natural Hook" and there isn't any argument possible.

Fast Transients (http://www.d-n-i.net/boyd/pdf/fast_transients.pdf)



Examples
Blitzkrieg vs Maginot Line Mentality (1940)
F-86 vs MiG-15 (1951 - 53)
Israeli Raid (1976)

The plane that cannot slow down faster (Bleed energy faster) cannot turn a faster turn rate or a smaller turn radius during a turn from high speed to corner speed. Once at the stall the plane can be pitched into a nose low turn to maintain corner speed. The Natural HOOK describes a decreasing radius turn as the plane BLEEDS ENERGY from high speed to corner speed. If the plane can't slow down quickly it won't reach corner speed quickly and therefore the Natural HOOK will be a slower turn rate and a larger turn radius compared to the faster e-bleeding plane. That is fact.

If the plane ahead pulls the power it can decelerate to a lower speed faster and then dive at a higher dive angle at corner speed sooner. If the plane behind doesn't pull the power it will not reach corner speed as quickly unless it BLEEDS ENERGY fast even with the power on. If it too pulls the power then it too will BLEED ENERGY faster and reach corner speed sooner from a high starting speed.

You can choose to ignore the facts and can prefer to play a game that models less energy bleed for your favorite plane, while the physical facts remain factual. Energy bleed is a double edged advantage/disadvantage in reality. The game is a game.

The game models light planes as double superior as if drag-loading is not even a consideration. Light planes should decelerate faster because they are light and that should then require more power to accelerate them for the same reason. It takes less power (drag force) to decelerate lighter planes. It therefore takes more power to accelerate lighter planes against the force of drag. Of course, and I only have to add this because too often people claim that I ignore this, it takes more engine power to accelerate higher mass.

That is why the excess power formula has thrust divided by weight.

T/W

That is half the forces involved. The other half is drag loading where drag force is divided by weight.

D/W

Of course the lighter planes would accelerate faster in vacuum. There wouldn't be any D in D/W and the forces involved would only be T/W.

When air resistance is present, then the force of drag is present. The force of thrust is divided by weight

T/W

The same as it would be in vacuum.

The same weight divides the force of Drag.

D/W

Excess power is what is left when D/W is subtracted from T/W

T/W – D/W

W, or weight, divides (makes less) the power of thrust.

W, or weight, divides (makes less) the power of drag.

More weight means less acceleration due to thrust force.

Thrust force is the same, but weight decreases the ability to accelerate the greater weight.

More weight means less deceleration due to drag force

Drag force is the same, but weight decreases the ability to decelerate the greater weight.

I'm not ignoring the division of thrust force by weight. I am also not ignoring the division of drag force by weight.

If drag-loading is ignored the single inferior planes become double superior and I suspect that the Mig-15 will be modeled as double superior, a lower corner speed, and faster dive acceleration combined with a slower rate of deceleration in a vertical zoom climb. The F-86 will probably be modeled as a hit and run plane that must attack with advantage and leave before the second turn because the F-86 will be modeled with Energy WASTE like the Fw190s in the game.

Double inferior planes in the game decelerate fast without actually producing high g quickly as if these planes are modeled with air brakes, poor wing design, bad high g L/D ratios and sluggish non-agility.

Well this turned out to be along post.

HuninMunin
03-27-2008, 12:38 PM
It does sum all my thoughts on the general core FM though - good post.

JG14_Josf
03-28-2008, 01:35 PM
It does sum all my thoughts on the general core FM though - good post.

HuninMunin,

Thanks.

I wrote about and will continue to expand upon the concept of nose to tail geometry when employing energy tactics such as The Sustained Turn Technique (as originally described my Robert Shaw in Fighter Combat).

Any two planes can be compared for relative performance with this type of combat technique and employment of geometry. I prefer to elaborate on The Sustained Turn Technique when comparing two planes with accurate performance data on record.

The idea is to find two planes where one of the two is considered as an Angles Fighter and the other fighter plane is an Energy Fighter, since The Sustained Turn Technique was employed by an Energy Fighter to defeat an Angles Fighter.

Some possible match-ups for this type of evaluation are these:

Angles Fighter---------------Energy Fighter
Spitfire VB---------------------FW190A-4
Bf109G-2-----------------------P-47 (any version)
Mig-15--------------------------F-86


Of those possible plane sets to be evaluated for relative effectiveness while employing the Energy Fighters advantages against the Angles Fighters disadvantages the F-86 versus the Mig-15 offers the match-up that records the most accurate relative performance documentation.

So my intent with this next post is to describe how The Sustained Turn Technique can be employed to take advantage of Energy Maneuverability and how geometry plays a role in that employment.

The idea is to set up a comparative analysis so the idea is to place both planes ready to fight at the same altitude; same speed, and aimed at each other out of range much like the IL2 game sets-up a dogfight in the quick mission builder.

Before proceeding to describe this employment of geometry I am going to re-quote words from someone who was in the thick of air combat with that plane set: (http://www.acepilots.com/korea_blesse.html)


Blesse: Air-to-air fight was like a game. You had to know the rules. You had to know what you could do and what he could do. We had pretty good information on the MiG. It was a point defense airplane, smaller and lighter than the Sabre; it didn't carry as much fuel. Consequently it could out-climb us at any altitude and had more than double our rate of climb above 25,000 feet. It could outrun us at any altitude. So a MiG pilot had a lot to work with. But if you're an F-86 pilot you had a couple of things you could try with this gopher, and one of them is turn. You don't want to try to outclimb him if he's behind you. So you measure these things into the fact. When you first sight him you hope to get an advantage by getting in his rear quarter. You know that he's immediately gonna turn into you, and you need to know how to respond. You close in as close as you can. With fifty caliber machine guns you gotta get within 1200 feet to do any good. Most of the airplanes I shot down were within 400 to 1000 feet.

It's a matter of training and practice. What if he turns into you and gets too close, and you can't make that turn? You gotta know what to do. You gotta know that the nose goes up, and let him come down, and then when you come around you'll still be behind him. If you try to stay on his plane, you're gonna stall your aircraft. Pretty soon you're in trouble because he's gonna reverse his turn, and you're gonna be on the outside going away from him, and you're going to have him behind you. That's what we tried to teach. We tried to make sure that our people didn't unnecessarily expose themselves to a disadvantageous position in combat.


The set-up places a Mig-15 and an F-86 at the same altitude in level flight where both planes are flying toward each other at high speed. Both pilots are heading toward each other at full power as both pilots maximize energy production. In order to makes sense of how nose to tail geometry works a few visual references can illuminate the situation and prepare the reader for the thinking process working in the mind of the energy fighter during the time when both planes are approaching each other at the beginning of the fight.

http://4jg53.org/gallery/albums/userpics/87040_Turnradius.jpg

http://4jg53.org/gallery/albums/userpics/87053_Turnrate2.jpg

The F-86 and the Mig-15 pilot may use any tactic or technique to defeat the opponent after this set-up begins at the same altitude as both pilots head toward each other. In this illustration the F-86 pilot uses nose to tail geometry while the Mig-15 pilot fails to use nose to nose geometry despite any consideration of anything. This set-up intends to illustrate how the nose to tail geometry works during The Sustained Turn Technique. The charts merely help illustrate what is happening during the first pass after both planes merge toward each other.

The idea is to get inside the F-86 fighter planes head while the Mig-15 pilot follows a script (does not employ any defense against The Sustained Turn Technique). So...the F-86 pilot intends to create a nose to tail or two circle merge as the F-86 approaches the Mig-15.

If the game models the two planes as they exist on the EM Chart by John Boyd - The Sustained Turn Technique could work well for the F-86 in the game. If the Mig-15 is modeled in the game as double superior then The Sustained Turn Technique will be much more difficult to manage for the F-86.

The F-86 pilots will aim at the Mig-15 at first during the initial approach to the first merge. The Mig-15 can do the same or the Mig-15 pilot can try to set up a lead turn or one circle geometry merge – it doesn't matter because the F-86 pilot forces the issue either way.

If the Mig-15 moves in for a head-on shot at the first merge the F-86 pilot can sense that right away as the F-86 pilot begins to set up his nose to tail merge. The F-86 pilot will force as much lateral separation during the first merge as possible and that will be dependent upon what the Mig-15 pilot does during the approach.

Ideally the F-86 pilot will create less than one turn radius separation at the point where both planes merge and this is an important consideration whenever viewing what actually happens during any merge. If one pilot looks perpendicular to his flight path (9 or 3 o'clock) and finds the opponent perpendicular to his flight path (going the opposite direction) then that is the point where the two planes merge. At that point the other plane will either be exactly the same 90 degrees off (seeing the same thing out the window) or the opponent will have gained or lost angles at that point.

See this?

Both planes start heading toward each other and as both planes pass each other one plane will gain angles on the other plane or both planes will be exactly equal relative to each other (parallel) at the merge. The merge will be complete when the last plane views the opponent passing from the forward to the rear hemisphere.

The reason this is important to see concerns what happens before the merge and what happens after the merge. If the Angles fighter (the Mig in this case) is going for a head-on shot, that will obviously be a different situation compared to the Angles fighter who goes for a lead turn or the Angles fighter who goes for a one circle geometry, nose to nose, merge.

In any case the F-86 pilot forces a two circle turn and that can become a complex thing to imagine if the Mig-15 pilot tries to force a nose to nose merge.

We have to proceed with one case at a time so I'll proceed with the case whereby the Mig-15 pilot goes for the head-on shot and therefore the Mig-15 pilot does not go for the lead turn nor the nose to nose geometry.

Note: If you ever find a fighter combat player who does go for a nose to nose geometry turn during a merge you had better watch out because that one will shoot you down. It is almost unanimous that all players use two circle geometry even the ones flying the angles fighters (and therefore the angles fighters give up their geometric advantage).


So...the F-86 pilot has the Head-ON shooting Mig-15 out in the distance and approaching. The F-86 pilot has the Mig-15 as a dot in his gun sight. Now the F-86 pilot will begin to fly to the side of the Mig-15. The idea is to create separation and force a two circle geometry turn. As the F-86 pilot rolls away from the Mig-15 the Mig-15 moves to the left or right of the gun sight. The Mig-15, because it is going for the Head-ON shot, will then be lured into pulling lead since the F-86 will be moving off the Gun sight of the Mig-15.

Here the The Sustained Turn Technique becomes a technique rather than a simple ˜by the book' maneuver. The idea is to set-up the nose to tail turn at the right time and avoid any possibility of being hit when the opponent thinks he can get a Head-ON shot. The player would have to be familiar with this situation to understand it and for this illustration the idea is to assume that the Mig-15 pilot was unable or unwilling to pull enough lead to get the Head-On shot. The merge, in this case, becomes nearly parallel during the merge.

The nose to tail, or two circle geometry, turn now starts from an almost parallel situation where each pilot is looking at 9 or 3 o'clock and seeing each other turn into each other; suppose both are turning left and both see each other at 9 o'clock.

Note: Speaking in terms of clock possition is misleading since the actual merge during a turn will place the opponents up into their canopy as they bank and turn into each other during the merge. After the merge, however, both pilots are dealing with opponents in their rear-hemisphere.

Since the Mig-15 pilot did pull some lead (but not enough) the Mig-15 pilot should be gaining angles if anyone is gaining angles at this first merge. In other words; the Mig-15 is seeing a 10 o'clock F-86 while the F-86 is seeing a 8 o'clock Mig-15 just after the merge. This is hard to explain with words and what needs to be understood is the fact that both planes over-shoot eventually. What that means is that both planes end up in each other's rear-hemisphere after the merge. The only way that won't happen is in the case where one plane does manage a lead turn or ˜early turn' and for that to happen the other pilot would be asleep at the stick or allowing that to happen on purpose.

Timing is the key to the technique and to see this it may help to go back to the initial contact at long distance and walk through the progress as the two planes reduce range.

As the F-86 forces lateral separation (moves the Mig-15 to the side with a roll away from the Mig-15) the Mig-15 (who is going for a Head-ON shot in this case) takes away that separation by pulling lead on the F-86. The technique is to get the rolling away right; meaning, not too much and not too little and then to turn back into the Mig-15 at the right time, not too soon, and not too late. So...the F-86 moves the dot to the left, setting up a left hand two circle turn, and keeps the dot (as it grows larger in view and begins to take on the shape of a Mig-15) to the left until the range between the F-86 and the Mig-15 is ˜just right' and then the F-86 pilot turns into the Mig-15 with a maximum performance turn.

That ˜rightness' can be understood as the ability to let the Mig-15 think he can get a shot and remove that thought from his mind just at the right time. In other words the Mig-15 pilot isn't going to fly in front of you during the merge, rather the Mig-15 pilot is going to time his snap shot ˜just right' and just before it becomes ˜just right' for the Mig-15 pilot you are turning into him. That sets up a two circle geometry turn at high speed (well above corner speed and even above vertical maneuvering speed).

Both planes over-shoot each other (the Mig-15 gains more angles – perhaps) and the next step in The Sustained Turn Technique begins.

I don't want to pollute this thread with my meaningless drivel, however I will return to complete this later if possible.

Thanks again.

gkll
03-28-2008, 03:26 PM
Originally posted by JG14_Josf:
gkll,

I am at a loss as to why you fail to address my question while you think you have addressed my question.


<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content"> Do you assume that the Mig-15 would gain more energy over the F-86 in vertical diving and vertical zooming and/or turns at high speed and/or turns during a hammerhead or pitch/back? plane is the poor energy fighter. That is false.


What about vertical dive acceleration? Which Jet wins that race?


Well this turned out to be along post. </div></BLOCKQUOTE>

Yes it is a long post, pretty much too long to provide any kind of comprehensive reply especially to someone with the attention span of a gnat such as myself... that said...

You seem concerned about this manuevering, concerned that I don't understand the graph perhaps even... not so. The maneuvering you described does not sound like high g maximum rate turns, they sound like 'moderate maneuvers'. So my interpretation from your words is that we would be countering maneuvers in our Mig that are within our envelope, ie to the right of the stall line.

Josf said "The actual F-86 pilots went vertical. That is classic energy tactics described by Shaw. Pitch back, Sustained Turn Technique, Diving extensions, pull-outs, zoom climbs, and nose to tail geometry or Energy Tactics. Not angles tactics. Angles tactics favor the angles fighter (single superior) Mig-15."

Are these maneuvers carried out in the area where the Mig cannot fly? Sure sometimes, but when that is the case we are easing into towards angles fighting. So don't bother repeating what I have already said about the 86 owning the Mig under high g high speed manuevering, this is as obvious to me as it is to you, reread my previous posts perhaps.

The 86 will have weight+thrust minus drag available in a dive. Assume vertical so no complication from induced drag. The 86 is larger, likely has somewhat higher drag because of greater surface area and possibly cross sectional area, however it also has more weight to contribute to dive acceleration. On balance I would guess that the 86 has a general dive acceleration advantage. However in a vertical climb under full power all this weight is now added to drag with thrust to counter. On the upswing the Mig is better, particularly in the 'second half'of the vertical zoom, where drag lessens in effect (declines ~as the square of the speed) and it becomes a battle of weight and power. Fair enough?

You really don't appear to get what I am trying to say: the Mig is an aircraft with powerloading and wingloading advantages over the Sabre. It has some issue with design which kills its ability to run out to a stall line similar to the 86 (if we trust the graph, other (internet) sources are not so clear that this was the case). IMO this stall line for the 15 represents bad design, I maintain that typically if an aircraft has less wingloading it will have a stall line further to the left if anything. Obviously wing design lift factors etc etc can reverse this. Or bad handling as we have discussed. However this matchup is not what I would call 'typical'.

I haven't discussed or brought up the game, however since you did I would ask why you are so sure the game doesn't model D/W in some fashion?

Your 'hook' stuff.... allow me to repeat myself, whereas you can pop flaps and chop throttle to achieve this 'e-bleed' effect the inverse is not possible. So id prefer the plane with less inherent e bleed under heavy maneuvering.

You have with this matchup (sabre/mig) what seems to me to be atypical, you have a plane with ~25% better powerloading (Shaw would call this the e fighter) <and> ~10% less wingloading (Shaw would call this the angles fighter), this plane is the Mig. However by the graph we see the Mig has a problem with its handling, I still maintain this is not 'typical'.

I have clearly expressed how my reading of all this would lead to my choice of tactics on a head on merge for these aircraft. Yours are different. I would love to try it out.

gkll
03-28-2008, 03:39 PM
Originally posted by JG4_Helofly:
Interesting discussion.

The more I read in here, the more I have the impression that the gaming world is not very close to RL.
In il2 there are 2 options: speed or turning. If you fly a fw 190 or a p 51, don't touch your ailerons or your elevator. If you fly a spit: stick back!
So what is the high manoeuvrability for, the 190 have? Even with the high roll rate I can't get away from a spit at high speed. I even prefer to simply push the stick full forward then rolling over and dive because the second manoeuvre takes longer. If you pull too hard you will loose very much speed and stall, if you are easy on the stick you are a nice slow moving target.


So the theorie of manoeuvrability for dogfight is interesting, but does not seem to work in this game IMO. If you don't have a big energy advantage in a fw 190 against a spit for exemple, you can start running for home.
This is my opinion after several years of playing this game. Manoeuvrability is nice if you are approaching at high speed and you have to correct your flight path for the shot. In such a case the 190 is better than the 109.


Now the question about manoeuvrability today whith modern jets. IMO it's very dangerouse to run away from an enemey if you are already close to him, because he could simply fire a medium range missile and it's game over for you. So if you can't hold your nose in his direction you will soon be dead. That's how I would explain it, but I am by far not an expert.

Just my 2 cents

Well I am not clear what you think should be possible? In game we can practise our tactics, read books, refine our approach, utilize modern BFM, all in a nice structured and predictable environment. RL was none of these. So don't expect 'historical' results, you'll be disappointed.

I pursued this issue of the e-fighter staying to 'fight it out' with an angles fighter, you know, this fabled 'e-fighting' as it is termed on the net. I wanted to engage zeros with a spit, I wanted to directly contest the airspace and not disengage after each 'pass'. When I talked to Andy Bush over at SimHQ about this he said 'you can't lag a zero forever', a pithy statement which says more than it seems at first glance (Bush is an ex military pilot). There is a point where if the e-fighter has failed to get a kill, it is suicide to remain 'in close', you must get out of dodge.

If you are tackling a fighter which has wingloading <and> powerloading advantages (say a spit 25 at 2000 m vs a 190) then why would you expect, going up against a well practised, calm, fully SAware BFM capable foe that you will be able to do anything real with your roll rate? Sure in RL, not here. It doesn't mean the game is wrong, not at all. It <may be> wrong, but what you complain of is no proof of this, at all.

gkll
03-28-2008, 03:43 PM
Originally posted by Kettenhunde:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Turning got back on the table.

This is what I disagree with. Maneuverability got back on the design table, not turning. That is a fact.

The previous aircraft where designed in a time when the thinking was that dog fighting was dead due to missile technology.

The next generation was designed with the fact dog fighting was still a reality. In a dogfight you need maneuverability.

All the best,

Crumpp </div></BLOCKQUOTE>

So did the improvement happen in thrust, lift vector performance, or roll? Relatively? Roll improved a lot, but my point is lift vector performance improved most. I guess it is true I don't know this for a fact.

JG14_Josf
03-28-2008, 05:38 PM
The 86 will have weight+thrust minus drag available in a dive. Assume vertical so no complication from induced drag. The 86 is larger, likely has somewhat higher drag because of greater surface area and possibly cross sectional area, however it also has more weight to contribute to dive acceleration. On balance I would guess that the 86 has a general dive acceleration advantage. However in a vertical climb under full power all this weight is now added to drag with thrust to counter. On the upswing the Mig is better, particularly in the 'second half'of the vertical zoom, where drag lessens in effect (declines ~as the square of the speed) and it becomes a battle of weight and power. Fair enough?

gkll,

Fair?


However in a vertical climb under full power all this weight is now added to drag with thrust to counter.

What does that sentence mean?

While diving down; the effect of gravity is the same as going up and that effect is 9.8 m/s/s for any object Mig-15 or F-86 at any load-out. Both are accelerated the same up or down by gravity. The mass difference accounts for a drag loading difference and that drag-loading difference remains a drag-loading difference even if no gravity exists. You did acknowledge straight up and straight down trajectories for simplicity.

Here is your sentence again:


However in a vertical climb under full power all this weight is now added to drag with thrust to counter.

How is all that weight now added to drag? The drag loading can be expressed as D/W where total drag force is divided by weight. The higher the weight the less will be the rate of deceleration caused by the same, constant, drag force.

How is it that weight adds to drag?

Both planes are going straight up. Neither plane can accelerate. Both planes will decelerate. One plane will decelerate at a faster rate than the other plane. If you are suggesting that the Mig-15 (which you admit to having a slower rate of acceleration going vertically down) will decelerate slower than the F-86 then you can say so.

You can say:

The F-86 accelerates faster going vertically down.
The F-86 decelerates faster going vertically up.

You can be more specific, and I would appreciate this too.

Starting at the same speed and from the same altitude going straight down the F-86 will accelerated faster

Starting at the same speed and from the same altitude going straight up the F-86 will decelerate faster.

Gravity accelerates both planes at the same rate going down.

Gravity decelerates both planes at the same rate going up.

Engine power is the same for the F-86 going down and up.
Engine power is the same for the Mig-15 going down and up.

Drag force is the same (at the same speed and same altitude) going down and going up – for both planes (it does not change from down to up, yet it is not the same for both planes).

Weight does not change from down to up.

You can say this:


However in a vertical climb under full power all this weight is now added to drag with thrust to counter.

What does that mean?

Do you mean that the gravitational force accelerating the plane going down is now a decelerating force added to the decelerating force of drag while going up?

That force is 9.8 m/s/s and it is the same 9.8 m/s/s force that will decelerate the Mig-15 (at the same rate) and be added to the decelerating drag force of the Mig-15 (which is not known to be more or less than the F-86).

Drag-loading remains the same on the F-86 going up as well as down. In other words the high mass (high density) of the F-86 requires a lot of drag force to decelerate that high mass going up as well as going down.

In other words if the Drag-loading advantage contributed to the higher rate of acceleration for the F-86 going straight down, then the Drag-loading advantage remains a Drag-loading advantage going straight up. It still takes a lot of drag force to slow down the higher mass F-86.


However in a vertical climb under full power all this weight is now added to drag with thrust to counter.

Net thrust force continues to be subtracted by net drag force (as both are divided by weight) and that net force negative is added to the negative rate of acceleration caused by gravity.

Gravity is the same for both planes.

T/W does not change for either plane going up or down (straight up and down).

D/W does not change for either plane going up or down.

T/W is not enough force to overcome D/W and gravity going straight up.

Gravity is enough to overcome D/W going straight down.

I'm not understanding how your words explain how the F-86 can accelerate faster than the Mig-15 going straight down and then how the F-86 slows down quicker when going straight up. It seems to me the reason why the F-86 accelerates faster going straight down is the same reason why the F-86 will decelerate slower going straight up and that is drag-loading. It takes more drag force to slow down the higher mass F-86 and that is why the lower power-loaded and higher wing-loaded, higher mass plane accelerates faster going down. Level flight, especially at speeds where induced drag dominates (slow speed), acceleration probably favors the Mig-15, however, when the nose is pointed down a larger force of drag is needed to keep the higher mass from accelerating at the rate of gravitational acceleration.

Gravity force does not change. Gravity force is the same. The difference between the Mig-15 and the F-86 is drag-loading, or, the amount of drag required acting against the mass which is forced by the gravity constant. This has been hashed out over and over again. Higher mass (higher density) requires more drag force to decelerate the higher mass. D/W is drag loading. Weight divides the force of drag. This is the same as weight dividing the force of thrust or T/W.

This is why the Ps equation works.

T/W – D/W

Add weight and dive acceleration increases, level flight acceleration decreases, and the ability to decelerate decreases (such as a vertically up zoom climb).


The 86 will have weight+thrust minus drag available in a dive. Assume vertical so no complication from induced drag. The 86 is larger, likely has somewhat higher drag because of greater surface area and possibly cross sectional area, however it also has more weight to contribute to dive acceleration. On balance I would guess that the 86 has a general dive acceleration advantage. However in a vertical climb under full power all this weight is now added to drag with thrust to counter. On the upswing the Mig is better, particularly in the 'second half'of the vertical zoom, where drag lessens in effect (declines ~as the square of the speed) and it becomes a battle of weight and power. Fair enough?

Not accurate – fair has nothing to do with it.


On the upswing the Mig is better, particularly in the 'second half'of the vertical zoom, where drag lessens in effect (declines ~as the square of the speed) and it becomes a battle of weight and power. Fair enough?

What is meant by the ˜second half' of the vertical zoom?

Both planes are at the same speed and both planes point their noses down. The F-86 (according to one source) gains velocity faster and will reach a slower corner speed sooner (according to the EM chart). Suppose both planes are at the same speed at the same altitude going straight down when, at the same time, both planes begin a maximum performance turn from down to up.

If the F-86 starts that turn at just above corner speed it may complete the turn and be starting the straight up attitude right at corner speed. If the F-86 does this and the Mig-15 tries to follow the Mig-15 will stall. How is that not a battle of weight and power?

Again; Both planes start diving and the F-86 reaches corner speed. The F-86 builds a little more speed and then starts a maximum performance turn from straight down to straight up and then the F-86 unloads the wings pointing straight up from corner speed.

A. The Mig-15 doesn't accelerate as fast going down.

B. The Mig-15 isn't at its higher corner speed when the F-86 is already at it's corner speed.

C. The F-86 is turning energy into g force at its lower corner speed before the Mig-15 can even reach its higher corner speed.

D. The Mig-15 can try to follow the F-86 when the F-86 starts turning but the Mig-15 will stall before it reaches the rate of acceleration (g) that the F-86 can reach.

E. The Mig-15 can wait until it reaches its higher corner speed and then turn but since it has a higher corner speed its turn rate will be lower and its turn radius will be wider even though it can pull slightly more g force at a higher corner speed.

F. By the time the F-86 is already going straight up (unloaded) the Mig-15 is still turning a slower turn rate and a wider turn radius.

G. By the time the Mig-15 turns a slower turn rate and a wider turn radius the F-86 is well up into its zoom climb.

H. No one knows which one ˜burns more energy' in the turn because that data is not available.

The rate of energy loss due to turning is not a function of weight it is a function of efficiency. Adding weight moves the accelerated stall line to the right or to a higher speed. The EM chart already shows that the Mig-15 is less efficient to a point that the F-86 can turn a slower corner speed at higher g. Why would someone arbitrarily assume that the F-86 would be less efficient at using energy to accelerate mass on the lift vector compared to the Mig-15? In other words why would anyone assume that the higher mass plane was automatically going to burn more energy when turning?

A plane that burns more energy moving air out of the way (pressure drag?) and less energy thrusting air mass opposite the lift vector (dynamic pressure?) will have a higher D in L/D and a lower L in L/D and if that low L and high D is even worse at high g then that plane will burn energy rather than use energy to turn.

Here: (http://www.flightlab.net/pdf/8_Maneuvering.pdf)


The maximum lift line, or CLmax boundary, takes its parabolic shape from the fact that lift is a function of velocity squared (because lift is proportional to dynamic pressure, q, which is itself proportional to V2). You can draw the lift line based purely on an aircraft's 1-g stall speed at a given weight. At least you can for speeds to about Mach 0.3. Above that, compressibility effects take over, CLmax declines, and the slope of the curve decreases.

What that says, if I have it right, is that the accelerated stall line is a curve that is ideally a function of velocity squared (because lift is proportional to dynamic pressure, q, which is itself proportional to V2), so, the shape of the accelerated stall line is determined by that relationship between airspeed and the square of that airspeed because dynamic pressure (lift force) is velocity times velocity. That is a lot of lift force – ideally.

A barn door would probably not plot out with an ideal accelerated stall line. Round tubes for wings would probably not plot out an ideal accelerated stall line. Wings with radiators stuck on them would probably not plot out an ideal accelerated stall line.

Wings with leading edge slats that open at anyspeed, any g, because they open by dynamic force associated with AOA may be wings that plot out a more ideal accelerated stall line or not and assuming that all planes plot out the same accelerated stall line is probably prone to error. Assuming that a plane that is more massive will be a plane that plots out a poor accelerated stall line is another assumption that is probably prone to error.

Bud (http://migluver.wordpress.com/2007/10/08/f86-sabre/)


But we could outperform them with the F-86's slab tail, we could turn faster than they could, we could dive faster, and we could pull out quicker.


On the upswing the Mig is better, particularly in the 'second half'of the vertical zoom, where drag lessens in effect (declines ~as the square of the speed) and it becomes a battle of weight and power. Fair enough?


I haven't discussed or brought up the game, however since you did I would ask why you are so sure the game doesn't model D/W in some fashion?

I do not code games. I've seen some of the code since someone broke the code and it remains a mystery. The Fw190A, in the game, acts like a very large plane by measure of density compared to the Spitfire V in the game. My figures show the Fw190 to be twice the size of the Spitfire V if weight is held at the ratio recorded in historical documents. That is a wild guess because there isn't any way of knowing if weight is at the proper ratio.

I can ask you a similar question (similar because there isn't anything here but speculation) and consider what the game could do if the programmers added weight on a slider. You can ignore this as you see fit and I can understand if you do; it is expected actually.

If the factor of weight was adjustable in the game and the player could map that variable to a slider it would be possible to see how the game models drag loading.

A player could spawn in at combat weight on the runway. The player could then move the weight slider to zero and see if the plane is displaced by air. If the plane is displaced by air at zero then the plane would begin to accelerate upward. The player could then add weight and stop the acceleration. If the player adds too much weight the plane will accelerate downward.

That would be a good test for drag loading and all it would require is an adjustable weight control.

The player could then see what happens with the engine on under normal flight, say, during level flight. What would happen if the player reduced weight to zero during a level cruise?

If a player were in combat with friends on a dog-fight server and an opponent was on his six in a dive. What would happen if the player added a whole lot of weight?

What would happen during an unloaded vertical zoom climb if the player added a whole lot of weight? Would it slow down even faster because gravity was pulling the plane down faster or would it slow down less fast because drag was even less able to slow it down. How much weight removed would be needed to allow the plane to hover straight up like a helicopter and would the plane rotate around the roll axis while hovering?


Your 'hook' stuff.... allow me to repeat myself, whereas you can pop flaps and chop throttle to achieve this 'e-bleed' effect the inverse is not possible. So id prefer the plane with less inherent e bleed under heavy maneuvering.

It isn't "my" ˜hook' stuff....and I understood what you said the first time. I too prefer a plane that is not crippled in the game with a mysteriously inefficient wing that wastes energy for very little gain in angles.


You have with this matchup (sabre/mig) what seems to me to be atypical, you have a plane with ~25% better powerloading (Shaw would call this the e fighter) <and> ~10% less wingloading (Shaw would call this the angles fighter), this plane is the Mig. However by the graph we see the Mig has a problem with its handling, I still maintain this is not 'typical'.


Shaw also stated that the numbers on paper do not tell the whole story. The F-86 versus Mig-15 match-up led Boyd to his discovery of "Fast Transients" and the identification of a Natural Hook or rapidly decreasing velocity during a maximum performance decelerating turn where turn rate is fastest and turn radius reaches the smallest fastest.

My guess is that you will maintain whatever you want and that is fine by me. If the new game does end up modeling the Mig-15 and F-86 we can then see of the game is accurate to the chart. We can certainly find that out since the chart does exist. My guess is that the Mig-15 will be modeled with a much lower corner velocity and therefore the F-86 will be modeled as double inferior.

If, on the other hand, the game models the F-86 accurate relative to corner velocity on the chart and relative to the Mig-15 on the chart, then that match-up, in the game, will be a really good fight between an energy fighter and an angles fighter.


I have clearly expressed how my reading of all this would lead to my choice of tactics on a head on merge for these aircraft. Yours are different. I would love to try it out.

Me too.

Kettenhunde
03-28-2008, 08:00 PM
So did the improvement happen in thrust, lift vector performance, or roll? Relatively? Roll improved a lot, but my point is lift vector performance improved most. I guess it is true I don't know this for a fact.


Increasing thrust directly increases the angle of bank we can sustain. Our load factor limits go up when we increase our thrust available.

Now when the aircraft is at a high angle of attack, a portion of thrust does directly contribute to lift.

With thrust vectoring, we can increase this thrust lift of the design.

Make sense now?

I agree that all aspect missiles make conventional energy tactics obsolete. That is a good point raised by some of the other participants in the thread.

All the best,

Crumpp

gkll
03-28-2008, 10:25 PM
Originally posted by Kettenhunde:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">So did the improvement happen in thrust, lift vector performance, or roll? Relatively? Roll improved a lot, but my point is lift vector performance improved most. I guess it is true I don't know this for a fact.


Increasing thrust directly increases the angle of bank we can sustain. Our load factor limits go up when we increase our thrust available.

Now when the aircraft is at a high angle of attack, a portion of thrust does directly contribute to lift.

With thrust vectoring, we can increase this thrust lift of the design.

Make sense now?

I agree that all aspect missiles make conventional energy tactics obsolete. That is a good point raised by some of the other participants in the thread.

All the best,

Crumpp </div></BLOCKQUOTE>

Hi there,

Actually I was just trying to be clever with my 'lift vector performance' (I had in mind an Eagle) not some new bird with thrust vectoring....

However now that you bring it up (thrust vectoring) I see I don't get it.

So as you describe it implies nozzles pointed 'down' (away from the lift vector)? This could help at high speed by unloading the wing? At low speed it seems you would still need to turn the nozzles toward the lift vector to just spin the bird around.

No I don't get it....

Kettenhunde
03-29-2008, 05:28 AM
Hi gkll,


So as you describe it implies nozzles pointed 'down' (away from the lift vector)?

What happens is that at high angles of attack, our thrust vector is pointing downward. This offsets weight at the rate of sin <angle>.

The angle we use is called the thrust angle. It is found by adding the angle of attack to the inclination of the thrust axis with respect to the chord line.

Thrust vectoring increases the inclination of the thrust axis with respect to the chord line.

Thrust contribution to lift then can be expressed as:

Thrust contribution to lift = Gross Thrust * Sin <thrust angle>

This offsets weight which actually reduces the lift production.

The thrust gains for the lift limit are generally small in comparison to the load factor gains.

Angle of bank is directly tied to load factor in a fixed relationship.

Fro example, a 60 degree bank will always yield a 2g load factor in a turn. It does not matter what aircraft you make that bank in. An FW190, a Spitfire, or a 747 will all produce 2g's at 60 degree of bank.

This angle is bank and aircraft can sustain is tied directly to the amount of excess thrust. The more trust, the more angle of bank we can sustain.

Does this help to clear things up some?

If we are in a level sustained turn and want to climb at the same time, we need a very large amount of excess thrust to do it. Rolling the vector of lift below the horizon makes for very efficient and large thrust gains in comparison if our performance is thrust limited at a particular velocity.

All the best,

Crumpp

gkll
03-29-2008, 11:25 PM
Originally posted by Kettenhunde:
Hi gkll,

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">So as you describe it implies nozzles pointed 'down' (away from the lift vector)?

What happens is that at high angles of attack, our thrust vector is pointing downward. This offsets weight at the rate of sin <angle>.

The angle we use is called the thrust angle. It is found by adding the angle of attack to the inclination of the thrust axis with respect to the chord line.

Thrust vectoring increases the inclination of the thrust axis with respect to the chord line.

Thrust contribution to lift then can be expressed as:

Thrust contribution to lift = Gross Thrust * Sin <thrust angle>

This offsets weight which actually reduces the lift production.

The thrust gains for the lift limit are generally small in comparison to the load factor gains.

Angle of bank is directly tied to load factor in a fixed relationship.

Fro example, a 60 degree bank will always yield a 2g load factor in a turn. It does not matter what aircraft you make that bank in. An FW190, a Spitfire, or a 747 will all produce 2g's at 60 degree of bank.

This angle is bank and aircraft can sustain is tied directly to the amount of excess thrust. The more trust, the more angle of bank we can sustain.

Does this help to clear things up some?

If we are in a level sustained turn and want to climb at the same time, we need a very large amount of excess thrust to do it. Rolling the vector of lift below the horizon makes for very efficient and large thrust gains in comparison if our performance is thrust limited at a particular velocity.

All the best,

Crumpp </div></BLOCKQUOTE>

Yes I get it now, thankyou. Still there would be a use for applying simple rotation to the aircraft via the nozzles, at low speeds where the elevators are not as effective? I seem to have a visual memory of nozzles being used to flip some russian bird around in a second or two at <low> speed, some airshow or other....

Kettenhunde
03-30-2008, 04:33 AM
Still there would be a use for applying simple rotation to the aircraft via the nozzles, at low speeds where the elevators are not as effective?


You can't have supermanuverability without thrust vectoring!

There is no substitute for excess thrust if we want to improve aircraft performance.

That's why we have thrust vectoring, to increase that inclination of the thrust axis with respect to the chord line and improve our turning ability!

All the best,

Crumpp

JG14_Josf
03-30-2008, 07:39 AM
Yes I get it now, thankyou. Still there would be a use for applying simple rotation to the aircraft via the nozzles, at low speeds where the elevators are not as effective? I seem to have a visual memory of nozzles being used to flip some russian bird around in a second or two at <low> speed, some airshow or other....

gkll,

I wonder about that too. Since the nozzles thrust mass out the back (not a prop in the front) the change of angle of that thrust is bound to change the handling or CG (center of gravity) as airspeed varies.

Nasa (http://www.grc.nasa.gov/WWW/K-12/airplane/vecthrst.html)
http://www.grc.nasa.gov/WWW/K-12/airplane/Images/vecthrst.gif

Going very slow the main wings will be producing very little lift force and at high speed and high g the main wings will be producing a whole lot of lift force and that force is centered between the nose and the tail. Lift force is not at the nose and not at the tail. Lift force is centered between the nose and the tail.

Thrust force is behind the lift force center for a jet. Thrust force for a WWII prop plane with the prop blades at the front are ahead of the main wing lift force.

Tail elevator planes (not canard type control surface planes) have a force of lift that is behind the main wings and that too is relative to the CG (center of gravity).

http://www.boingboing.net/200712051035.jpg

That one has vectored thrust, elevator, canard, and the main wing. I'd like to see the various positions of the thrust nozzles during slow and fast maneuvering.

Kettenhunde
03-30-2008, 08:03 AM
Going very slow the main wings will be producing very little lift force and at high speed and high g the main wings will be producing a whole lot of lift force

gkll,

At wings level the amount of lift force produced remains constant no matter what the velocity.

When the aircraft is banked, the wings will produce only the amount of lift required to meet the horizontal and vertical component.


We can also see in the figure that the lift force curve is perfectly constant,

http://www.av8n.com/how/htm/4forces.html#fig-force-ias

Don't confuse the effects of powers and forces.

All the best,

Crumpp