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Bankoletti
11-26-2010, 04:23 AM
In reality - do worse turning planes bleed more energy during turns?

In IL-2 simulation it certainly seems so - if we only take a look at Spitfire vs 190 or A6M vs Hellcat as two representative "pairs" - Spit and Zero not only turn better (rate and radius) at usual speeds, but also retain energy better (Hellcat and Focke bleed speed much faster through turns since they achieve much higher AoA than Spit and Zero during a turn with the same parameters). Is this also the case in reality?

M_Gunz
11-26-2010, 10:07 AM
True though in flying you have to be careful about your speed and crossing into stall. The 190 needs more speed than the Spit to turn at the same G's. Getting co-speed slow and trying to follow in a turn is a major disadvantage for 190 vs Spit.

By the same token a 190 should be able to turn a wide fast (over 500 kph?) circle that the Spit can't follow, but can turn inside while losing distance. Add a slight climb and the shoot from behind gets much more difficult.

ElAurens
11-26-2010, 07:09 PM
Do remember that the F6F could not stay with the "Zeke" for more than about half a turn in reality.

The laws of physics are a harsh mistress.

M_Gunz
11-26-2010, 09:32 PM
It says a LOT for the Hellcat pilot to arrange to have hung on for a half-turn! I'm sure he didn't start co-speed!

Bankoletti
11-27-2010, 08:16 AM
Originally posted by ElAurens:
Do remember that the F6F could not stay with the "Zeke" for more than about half a turn in reality.


Sounds pretty logical, but was this the case also at high speeds, where Zeke controls became heavy? I was under impression that in reality Hellcat was more maneouverable than the Zero at high speeds - it could roll and turn faster than the Zero, so it could outmaneouver (for example outscissor) the pursuing zero and shoot it down. In IL-2 trying anything like this would be a suicide in most cases, since Hellcat while indeed more maneouverable than Zero at high speeds, on the other hand bleeds energy so fast it becomes a slow sitting duck in no time and the outmaneouvered Zero can simply climb away and came back down with his guns blazing.

BTW, I really do not want to turn this into a Hellcat vs Zero thing, it's just an example. The same goes for any other similar pair of planes, for example Tempest and early 109Gs, or Fw190A vs SpitV. If for example you are flying at high speed in your 190 and you are caught by a diving spit, and then you try to out-barrel-roll him with a Fw190 (a maneouver which if memory serves me well LW pilots used in reality to outmaneouver pursuing spits due to much better roll), you'll bleed speed very fast and become slow long before outmaneouvering him. Once slow, spit eats you up. The only case where I've been able to use scissors to outmaneouver the spit and reverse the hunter-prey role when I was in 190 and followed by a SpitV was in a steep dive - the dive enables 190 to keep the speed up, where you can indeed outscissor a Spit. Essentially, gravity makes up for a speed-bleed.

K_Freddie
11-27-2010, 09:41 AM
If you're not outturning a better turning plane, you're doing something drastically wrong.
http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

JtD
11-27-2010, 09:42 AM
F6F vs. A6M is probably not the best example to illustrate high energy bleeds, because a well flown F6F can hold its own in a dogfight against the A6M. In particular if it involves the later, heavier A6M models. Not in a pure, sustained turn fight though, that's for sure.

If you need to keep the speed up, try diving manoeuvres, and keep that tendency in the dogfight.

ROXunreal
11-27-2010, 10:44 AM
J2M is an example of a plane that can turn very tightly but bleeds a lot of E doing so. It can trun like a spit, but in sustained truns it will soon be left hanging dead in the sky.

M_Gunz
11-27-2010, 02:09 PM
Originally posted by Bankoletti:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by ElAurens:
Do remember that the F6F could not stay with the "Zeke" for more than about half a turn in reality.


Sounds pretty logical, but was this the case also at high speeds, where Zeke controls became heavy? </div></BLOCKQUOTE>

How about where one bounces the other and they're not at close to the same speed? Like Zero drops on Hellcat, is it bye-bye Hellcat? LOL!

Co-speed is for trying to follow and shoot from a fixed distance isn't it? Otherwise... why else?

Bankoletti
11-27-2010, 05:56 PM
Gentlemen I think I might have made a wrong impression. I'm not asking for an advice on how to beat the Zero with Hellcat (or SpitV with the 190) in IL-2. Both BnZ planes are vastly superior to their counterparts and you can rack kills up like there is no tomorrow against them when you use them right. My personal best if I remember correctly is 8 Zeros and Oscars with a Hellcat on a full real online server - and it can get even uglier on pit off I guess. Using the stock Hellcat with a lot less ammo than it had in reality. BUT - that's using the plane as a pure BnZ-er without practically any kind of maneouvering with enemies.

But then again, planes like Hellcat, Tempest or Mustang were in reality known to outmaneouver planes like Zeke and 109 at high speeds - particularly outscissor (combining both the roll and pitch, which should both get heavy at said opponent planes at high speeds). Now if you try anything like this in IL-2 you'll get in trouble in no time since any maneouvering at high speeds slows you down so fast you have no time to outmaneouver your opponent that way.

This discrepancy has led me to a thought that the E-bleed at high speed maneouvering might be a bit too high in IL-2 flight modelling.

Sorry M_Gunz, I have no idea what you are talking about. Could you please rephrase yourself?

M_Gunz
11-27-2010, 07:43 PM
Okay. If I'm in a Hellcat and close on a Zero at 60 mph relative, his turn and stick forces will be at lower speed than mine and vice-versa. Sometimes in combat both planes are near the same high or low speed, often not. So when talking about at high speeds they compare one way while at low another there are still the cases where one is significantly (10+%) faster than the other.

When I see that the Hellcat could stay with a Zeke for 180, I guess they mean in a desired tactical situation that should be part of the context but is not because those people it was made for knew it already, and I can only guess what it is based on USN training and doctrine materials I know of and remember... like keep your speed up and make slashing attacks!

M_Gunz
11-27-2010, 08:51 PM
Originally posted by Bankoletti:
But then again, planes like Hellcat, Tempest or Mustang were in reality known to outmaneouver planes like Zeke and 109 at high speeds - particularly outscissor (combining both the roll and pitch, which should both get heavy at said opponent planes at high speeds). Now if you try anything like this in IL-2 you'll get in trouble in no time since any maneouvering at high speeds slows you down so fast you have no time to outmaneouver your opponent that way.

Perhaps it depends on what you think of as high speeds. Engaged in maneuver combat you want to run up to your maneuver speed, the IAS you can pull full stick on ONE AXIS and not break your plane. Any faster and you have to take care to use less stick and your radius will be wide.

You know that pulling the stick diagonally makes more drag than banking first then pulling back? And when you switch bank on the scissors, try rolling in the direction you're already banked until you bank the other way or unloading while changing your bank instead of going back and forth while under load which is what rolling and pitching at the same time does. You might even combine some porpoising in there, it will make you harder to hit by his wingman.

BillSwagger
11-27-2010, 10:44 PM
Is this also the case in reality?

I've had planes pass me head on, cut a tight 180 and catch up to me with in a few seconds after their turn.
If you actually calculate the turn time, something like 3-4 seconds for 180 degrees, and their start speed, it would be something like a 12-15G turn. I'm not sure how real that kind of turn is, i would think a tight turn bleeds more speed until it reaches sustained turn performance.

M_Gunz
11-28-2010, 12:39 AM
Love to see a track of that!

freakvollder
11-28-2010, 09:31 AM
Originally posted by Bankoletti:
In reality - do worse turning planes bleed more energy during turns?

In IL-2 simulation it certainly seems so - if we only take a look at Spitfire vs 190 or A6M vs Hellcat as two representative "pairs" - Spit and Zero not only turn better (rate and radius) at usual speeds, but also retain energy better (Hellcat and Focke bleed speed much faster through turns since they achieve much higher AoA than Spit and Zero during a turn with the same parameters). Is this also the case in reality? I like to say something;
Your observation is true because of a simple reason --> wing-loading, is the main factor here, in the case of turning at corner speed(low speed turning). The Spitfire has a much lower wing-loading as the Fw190A. So how do these two plane hebave in a turn? First remember what you need to turn an airplane?? Naaa? Yes! Lift! Airplanes create lift by inducing the so called angle-of-attack(AOA). The spitfire need a relatively lower AOA to make the same turn as the Fw190A does because the wings are much bigger compared to its weight. We know also that a higher AOA cause higher drag. The higher the AOA in a turn is (not only in a turn) the higher the drag will be. So the solution is simple. The lower wing-loaded plane induces less drag than the higher-wing-loaded plane. The lower-wing-loaded plane in our case the spitfire can turn with much lesser induced drag by its wings, that is the reason because the energy loss(correctly speed loss) is at a lower rate in the turn.
correct me if I am wrong here! http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

S

JtD
11-28-2010, 11:02 AM
I think Bill has pointed in the right way - in game you will very often make extreme manoeuvres, applying maximum control force, pushing the airframe to the limit. Different story in real life, where the 50lb stick force actually mean 50lb, not just 1lb for the joystick. This would make the manoeuvres more gentle overall, leading to less energy bleed, which would be beneficial for the planes with the higher energy bleed. It might explain where some of the differences between the game and real life reports come from.

As for the physics behind it, induced drag is roughly proportional to lift^2/wingspan^2. So if you take a Spitfire V at 3tons with 11.2m wingspan and a Fw 190A at 4tons with 10.5m wingspan, both doing the same turn, the Fw will bleed twice as much E as the Spitfire.

Bankoletti
11-28-2010, 11:05 AM
Originally posted by freakvollder:
correct me if I am wrong here! http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif


You appear to have overlooked the fact that induced drag at equal AoA is much higher at spit simply because its wing is much larger than the wing of Fw190. That's why it's not so obvious that at the same turn rate 190s wing creates more drag due to higher AoA, since both wings are not of the same area. Spits wing, while at lower AoA, might very well create more drag due to much larger wing-area.


Originally posted by M_Gunz:
Okay. If I'm in a Hellcat and close on a Zero at 60 mph relative, his turn and stick forces will be at lower speed than mine and vice-versa. Sometimes in combat both planes are near the same high or low speed, often not. So when talking about at high speeds they compare one way while at low another there are still the cases where one is significantly (10+%) faster than the other.

When I see that the Hellcat could stay with a Zeke for 180, I guess they mean in a desired tactical situation that should be part of the context but is not because those people it was made for knew it already, and I can only guess what it is based on USN training and doctrine materials I know of and remember... like keep your speed up and make slashing attacks!

Well, what I'm speaking about is a scenario where a Hellcat flies at about 500kph and a Zero jumps it and finds itself behind a Hellcat at, say, 100m at approximately equal speed (at 500kph Zekes controls should already be frustratingly heavy). Skilled Hellcat pilots, in reality, were able to outscissor such Zeke at those speeds and bring themselves to Zeke's tail and shoot it down, since Zekes controls were nearly frozen - Zeke couldn't match Hellcat in turn nor in roll at 500kph.

Try anything like that in IL-2 and Zeke will eat you up easily, since you bleed your speed so fast during scissoring. Once slow, Zeke of course outmaneouvers a Hellcat more than easily.

Bremspropeller
11-28-2010, 11:24 AM
Pulling 50lb stick-force once or twice isn't a big deal (especially when you're engaged defensive) - sustaining it is, however.
You just can't pull it all day or do it all the time.

Even more of a problem is standing the repeated onset of g-forces and retaining situational-awareness at the same time.

People don't NEARLY recognize how physically exhausting this stuff actually is.

That's the reason why modern fighter-pilots spend almost as much time in the gym as they spend in the cockpit http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif


the Fw will bleed twice as much E as the Spitfire.

Unless both planes actually have their throttles outside the idle-detent. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

freakvollder
11-28-2010, 11:30 AM
Originally posted by Bankoletti:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by freakvollder:
correct me if I am wrong here! http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif


You appear to have overlooked the fact that induced drag at equal AoA is much higher at spit simply because its wing is much larger than the wing of Fw190. That's why it's not so obvious that at the same turn rate 190s wing creates more drag due to higher AoA, since both wings are not of the same area. Spits wing, while at lower AoA, might very well create more drag due to much larger wing-area.
</div></BLOCKQUOTE>
No I don't have overlooked it http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif
The difference in wing-size is not significant. At the same AOA the spits-wing create much more LIFT but not that much more drag. It is simpler as you might think --> wing-loading is the deciding factor nothing else. The spitfire-wing is not a magic RAF secret http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

S

JtD
11-28-2010, 11:41 AM
Originally posted by freakvollder:

...wing-loading is the deciding factor nothing else...

Now you're really oversimplifying. Wing loading might be good as an indicator for a general tendency, but it certainly isn't the only deciding factor.

freakvollder
11-28-2010, 11:47 AM
Originally posted by JtD:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by freakvollder:

...wing-loading is the deciding factor nothing else...

Now you're really oversimplifying. Wing loading might be good as an indicator for a general tendency, but it certainly isn't the only deciding factor. </div></BLOCKQUOTE>
Must I repeat it again http://forums.ubi.com/images/smilies/blink.gif
If you want to make things complicated, please go ahead. http://forums.ubi.com/images/smilies/11.gif

Bremspropeller
11-28-2010, 11:52 AM
If you want to make things complicated, please go ahead.

Well, people have tried building airplanes based on "guessing" for a couple of thousand years - it took "science" to actually make it happen http://forums.ubi.com/images/smilies/11.gif

freakvollder
11-28-2010, 11:55 AM
Originally posted by Bremspropeller:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">If you want to make things complicated, please go ahead.

Well, people have tried building airplanes based on "guessing" for a couple of thousand years - it took "science" to actually make it happen http://forums.ubi.com/images/smilies/11.gif </div></BLOCKQUOTE>What do you want to say bremspropeller?

JtD
11-28-2010, 12:24 PM
Originally posted by freakvollder:
Must I repeat it again http://forums.ubi.com/images/smilies/blink.gif
If you want to make things complicated, please go ahead. http://forums.ubi.com/images/smilies/11.gif

No need to make it complicated, it's enough for me if it is more accurate. And as I have pointed out before, the relevant number here is spanloading, i.e. weight/wingspan.

A low wing loading generally allows for a lower stall speed which has its own benefits regarding level turning, but for energy bleed the deciding factor, if you want to reduce it to one, is spanloading.

M_Gunz
11-28-2010, 01:10 PM
Originally posted by Bankoletti:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by freakvollder:
correct me if I am wrong here! http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif


You appear to have overlooked the fact that induced drag at equal AoA is much higher at spit simply because its wing is much larger than the wing of Fw190. That's why it's not so obvious that at the same turn rate 190s wing creates more drag due to higher AoA, since both wings are not of the same area. Spits wing, while at lower AoA, might very well create more drag due to much larger wing-area. </div></BLOCKQUOTE>

Induced drag does have speed, wing area, aspect ratio and lift co-efficient. Speed can change and so can the lift co-efficient. Lift co-efficient changes directly with change in AOA. Wing area and AR stay the same. Please note, only speed and AOA change while the others remain constant. The change in speed and AOA both increase induced drag by the square of the change just as lift increases by the squares as well. So if you need twice the lift then by change in either speed or AOA or both you must double your induced drag. If you increase speed then you also increase parasitic drag, by another square of change. Mostly the change is made through pitch control to change AOA.

FW is made to run at higher speed. At low speed -for the FW- the AOA is relatively high compared to the Spit at the same speed which is not so low for the made to run slower Spit. But so what, each uses what it does and then the change is what matters.

But AOA can only be so much and then stall. So change in AOA has a limit. And speed... the more drag you pull the less your speed can increase without losing height, and pull enough drag you lose speed and lift which most players try to counter with more back-stick and then reach the stall under G's at speed maybe they don't expect or recognize.. but they do see the bleed!

I find that all these planes do fine in turns up to the point of stall. Pull them tiny bit harder and you cross into stall which slows you down a little and slows the turn rate. The slowing down of speed and turn rate compound by the second until you loosen up on the stick not just back to where it was when you were going faster but even less and you may begin to recover your speed.
Instead many players just pull more stick reflexively while cursing the heavy bleed they are causing if they even notice. What are they noticing? The target they are after and their relative positions and angles, everything else is background. I know because I've been there often enough, target fixated and not paying attention to my flying 'for a few seconds' which is all it takes. The snap roll or spin will change the fixation if it goes far enough, LOL! Difference between players is does it change the attitude of the player to in future stay aware of speed and turn rate and find tactical answers to 'not turning fast enough' or does the problem become plane is at fault?

At every IAS you can maintain certain G's without slowing. 1 G = straight and level flight, you can go top speed. Any more than 1 G required to turn flat and you must slow down. Fact of life we all accept. Heavy Speed Bleed OTOH happens when we cross a line that in sim you can't feel and must intuit through -continuing- change of speed and turn rate beyond change in stick pull. You get that then time to loosen up on the stick and switch to a different tactic if need be.


<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by M_Gunz:
Okay. If I'm in a Hellcat and close on a Zero at 60 mph relative, his turn and stick forces will be at lower speed than mine and vice-versa. Sometimes in combat both planes are near the same high or low speed, often not. So when talking about at high speeds they compare one way while at low another there are still the cases where one is significantly (10+%) faster than the other.

When I see that the Hellcat could stay with a Zeke for 180, I guess they mean in a desired tactical situation that should be part of the context but is not because those people it was made for knew it already, and I can only guess what it is based on USN training and doctrine materials I know of and remember... like keep your speed up and make slashing attacks!

Well, what I'm speaking about is a scenario where a Hellcat flies at about 500kph and a Zero jumps it and finds itself behind a Hellcat at, say, 100m at approximately equal speed (at 500kph Zekes controls should already be frustratingly heavy). Skilled Hellcat pilots, in reality, were able to outscissor such Zeke at those speeds and bring themselves to Zeke's tail and shoot it down, since Zekes controls were nearly frozen - Zeke couldn't match Hellcat in turn nor in roll at 500kph.

Try anything like that in IL-2 and Zeke will eat you up easily, since you bleed your speed so fast during scissoring. Once slow, Zeke of course outmaneouvers a Hellcat more than easily. </div></BLOCKQUOTE>

500 kph TAS in a Zero, below 10,000 ft he can't hold that speed in level flight, his IAS is already less. And when I am in-game it is IAS I go by. It is IAS that tells me what maneuver I can pull, how much.

Can any Zero fly level at 500 kph IAS at any alt? Hellcat can. With minimal swerve the Hellcat should be able to pull away. At over 400 kph the Zero has less ability to turn than the Hellcat and will lose more speed in the same turn. Unfortunately since he is behind by some distance, he doesn't have to turn as much to keep his nose on you. He is on your six. He also has less ability to climb even very shallow without slowing more than you and turning even less. Your plane has excess power while his is at or very near the limit. Who has more options? Who is able at that speed to sustain more maneuver?

BIG CAVEAT on that. If you do not trim well, if your stick wobbles or spikes, if you are not smooth and careful throughout then your Hellcat will not reach its maximum performance. One thing you can try is to add FILTER to your stick settings as a kind of 'dolby' for the spikes and incremental step flutter (from digitizing stick position, if the position is right between two values then the digitized result can flip-flop between the two) that can occur as well a very small muscle tremors that you may not notice but the stick hardware does. The heavier the hand on the stick, the less you will notice too.

The AI might be stupid but they always fly clean. Until you can fly better than 90% as well, life's a beotch.

He is on your six. Drop a little as you turn sideways slightly, you will keep your speed through losing a little height and 10m drop will spoil his aim. Don't reflex yourself into slowing down to where he is not having trouble just keeping up. You've already screwed up or he wouldn't be there, don't compound the mistake by slowing down more than a small amount.
What you do next shouldn't always be the same but perhaps a very shallow climbing spiral keeping speed high will do the trick. Or there's the old tried and true, split-S and dive that worked for WILDCAT pilots who didn't get too slow trying to dogfight Zeros. Rule one: don't get slow. Rule two: don't dogfight Zeros. Rule three: if you violate 1 & 2 then don't expect immediate escape by diving, twist and turn on the way down.

Regardless of how heavy his stick is (which BTW trim can cover that), he doesn't have the power to go fast +and+ maneuver or climb better than you. Your biggest problem is his aim and his gun range. Your friends are your height and your greater excess power at high speed. He -can- turn to get you in sight but every bit costs him speed. How you avoid getting shot while keeping speed up is your problem but you have plenty of options besides flat turns hard enough to bleed more than small amount of speed. Perhaps you should spend time working on those in solo flying practice without a distraction on your tail?

K_Freddie
11-29-2010, 05:38 AM
Ever thought of writing a book ?
http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

M_Gunz
11-29-2010, 07:27 AM
Ever thought of growing up?

K_Freddie
11-29-2010, 08:59 AM
It was a genuine question, but I'll reply http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif..

..so that it's acceptable to you ?
http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

M_Gunz
11-29-2010, 10:12 AM
Go buy a copy of Fighter Combat by Robert Shaw. That covers the entire subject well enough, why bother writing another?

And then there's the whole book as opposed to forum posts or even published paper thing. 4000 or 8000 words on a subject may seem like a lot to some people but it's nothing compared to a book unless it's a book for beginning readers.

I could write a real thin book on internet trolls perhaps. Something to match the depth they display.

ElAurens
11-29-2010, 10:45 AM
Originally posted by M_Gunz:
I could write a real thin book on internet trolls perhaps.

Personal knowledge is your friend here...

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

freakvollder
11-29-2010, 11:13 AM
Originally posted by JtD:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by freakvollder:
Must I repeat it again http://forums.ubi.com/images/smilies/blink.gif
If you want to make things complicated, please go ahead. http://forums.ubi.com/images/smilies/11.gif

No need to make it complicated, it's enough for me if it is more accurate. And as I have pointed out before, the relevant number here is spanloading, i.e. weight/wingspan.

A low wing loading generally allows for a lower stall speed which has its own benefits regarding level turning, but for energy bleed the deciding factor, if you want to reduce it to one, is spanloading. </div></BLOCKQUOTE>
spanloading http://forums.ubi.com/images/smilies/blink.gif never heard such thing before...?
Could you mean the aspect ratio?

S

Bankoletti
11-29-2010, 11:15 AM
M_Gunz, it appears I still haven't been clear enough. I know very well how to deal with Zeros in IL-2 simulation.

The point of this thread however is not "F6F vs Zero in IL-2 simulation", it's rather "F6F in IL-2 simulation vs F6F in reality". Or any other plane for that matter, the thread appears to revolve about this example (F6F vs A6M). Or more accurately: "Energy bleed during high speed maneouvering in IL-2 vs the same in reality".

Again, in reality an F6F could outscissor a pursuing Zero at high speed (or a Tempest a 109). In IL-2 simulation it can't. Why not? Because you bleed speed so fast that you are slow before you have outmaneouvered an A6M, which lead me to a thought that at high speed maneouvering planes in IL-2 simulation bleed speed faster than in reality.


Originally posted by freakvollder:
The difference in wing-size is not significant. At the same AOA the spits-wing create much more LIFT but not that much more drag. It is simpler as you might think --> wing-loading is the deciding factor nothing else. The spitfire-wing is not a magic RAF secret http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif


Sorry but that's completely wrong. We are not speaking about parasitic drag, but induced one. Induced drag is proportional to the wing area (and to the density of air and to the square of TAS - in the most simple form).


Originally posted by JtD:
As for the physics behind it, induced drag is roughly proportional to lift^2/wingspan^2.

Could you elaborate on this a bit more please? Where did you derive this dependance from? EDIT: Never mind, found it.

JtD
11-29-2010, 11:37 AM
Originally posted by freakvollder:
spanloading http://forums.ubi.com/images/smilies/blink.gif never heard such thing before...?
Could you mean the aspect ratio?

No, most certainly not. Aspect ratio is wingspan/mean chord. Spanloading, as stated already, is weight/wingspan. You will find that induced drag depends on that to a great extend. You can look up induced drag at wiki, but for their formula you have to remember that wing area * aspect ratio is nothing else but wingspan^2.


Originally posted by Bankoletti:
...at high speed maneouvering planes in IL-2 simulation bleed speed faster than in reality.

Il-2 is reasonably accurate in that regard. So what is probably different, is how the manoeuvres are performed in game. Sorry for the partial quote.

Erkki_M
11-29-2010, 12:31 PM
If you cant outmaneuver a Zeke off your 6, flying F6F at or above 400kmph-ish IAS in il2, there is 100% chance the fault is somewhere between the monitor and the seat.



Dont you dare to blaim your controllers lol. http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

kimosabi79
11-29-2010, 12:37 PM
The keyboard?

Bankoletti
11-29-2010, 12:54 PM
Did I step on someone's tail around here? Can't see any other reason for pointless ridiculing.

Of course people who contribute nothing but a silly mockery to debates usually can't provide tracks of any sort about how to do it consistently and tend to misinterpret things (in this case "ouscissoring so as to come to one's 6 and shoot him down" with a simple "shaking off").

I'd love to see anyone in an F6F try to maneouver with a well flown Zero tailing him, and succsessfuly outmaneouvering and shooting him down - at any speed (of course without diving away, outclimbing and coming back in a good ol' BnZ attack). Result of a heap of luck - yes. Consistently? Show me. Words are useless.

M_Gunz
11-29-2010, 01:53 PM
Originally posted by Bankoletti:
Again, in reality an F6F could outscissor a pursuing Zero at high speed (or a Tempest a 109). In IL-2 simulation it can't.

Depending on the pilot. Unless every Hellcat pilot who scissored with a Zero won the fight?

In IL2 you don't have to do much at 500 kph TAS to leave the Zero behind. You only have to avoid being hit for a while. The IL2 Zero can't even reach 500 kph TAS below 10,000 ft without diving, even on WEP.

What the Zero pilot needs to do is get the Hellcat to slow down and the tiniest bit of turn does that to the IL2 Hellcat or so I am informed. Same thing I've seen over and over about the 190's yet every blessed time I try these planes out, I only get more than a small loss of speed when I pull hard moves which ain't necessary at all in high speed scissors.

When you read about Hellcat pilots scissoring with a Zero in pursuit at 310mph, do they tell how hard they weave? Please? Huh?

My question is this: Why is MY COPY of IL2 so different? I don't use mods and I get these same general results since the demo I got in Sept 2001 yet I keep reading different, that my IL2 experience is impossible, so there must be another IL2 game out there. And what's even funnier is, the same thing happened before with 3 other sims as well!

My view is simpler. The statement "this can't be done in IL2" should be replaced with "I can't do this in IL2".

I need to start using my old sig line: When a pilot takes a plane up to see what it can do, he finds out what he can do with it.

K_Freddie
11-29-2010, 01:55 PM
Don't worry about it.. an occasional bit of historical banter won't do any harm... talk about putting one's big foot in it.

BTW.. there are plenty these tracks floating around. Actually the P40 would be a better match than the F6 against the zero.

M_Gunz
11-29-2010, 02:05 PM
Originally posted by JtD:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by freakvollder:
spanloading http://forums.ubi.com/images/smilies/blink.gif never heard such thing before...?
Could you mean the aspect ratio?

No, most certainly not. Aspect ratio is wingspan/mean chord. Spanloading, as stated already, is weight/wingspan. You will find that induced drag depends on that to a great extend. You can look up induced drag at wiki, but for their formula you have to remember that wing area * aspect ratio is nothing else but wingspan^2. </div></BLOCKQUOTE>

Might as well post the induced drag formula and show the relation. I figure you get span loading from weight, AR and wing area?

M_Gunz
11-29-2010, 02:22 PM
Originally posted by Bankoletti:
Of course people who contribute nothing but a silly mockery to debates usually can't provide tracks of any sort about how to do it consistently and tend to misinterpret things (in this case "ouscissoring so as to come to one's 6 and shoot him down" with a simple "shaking off").

LOL! How do you shoot a Zero in scissors unless you get behind him? In reality or in IL2? And HOW do you do that without slowing down more than he does? In reality or in IL2? Of course if you do start to get behind, the Zero can't slow down even more!

But HEEYYYYYYY, the F6F SLOWS DOWN TOO MUCH IN SCISSORS!

Please, you don't want to slow down but you want to get him in front of your guns then what you want is BnZ -or- ROLLING SCISSORS/YOYO and that's for when you come up from behind, not when he has gotten on your tail.

Don't they explain these things in war stories and combat reports? Oh.. wait... usually they don't but somehow "you just know".


Did I step on someone's tail around here?

The parts where you say "can't be done in IL2" when there are others who have copies that work like mine?
No, you didn't step on someone's tail but perhaps you stepped -in- something and haven't wiped it off?

Like I replied to you before, if you get serious bleed it means you've pushed the plane too hard.

Buzzsaw-
11-29-2010, 05:43 PM
Originally posted by JtD:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by freakvollder:

...wing-loading is the deciding factor nothing else...

Now you're really oversimplifying. Wing loading might be good as an indicator for a general tendency, but it certainly isn't the only deciding factor. </div></BLOCKQUOTE>

Correct.

The other factor is the design of the aerofoil and its tendency to resist compressibility effects.

For example, the P-51's semi-laminar flow wing resists compressibility much better than standard design wings at high speeds. It generates less drag at low G than a more conventional wing, and therefore generates more lift at low G's and the better lift allows it to turn better.

Put a P-51 and a conventional aerofoil equipped plane in 1G turns at 350 mph and the P-51 will easily outturn the other aircraft.

Same applies for the Tempest with its semi-laminar flow aerofoil.

M_Gunz
11-29-2010, 09:53 PM
1 G "turns"?

Kettenhunde
11-29-2010, 10:30 PM
Ahh bleeding energy.....

freakvollder
11-30-2010, 03:28 AM
Originally posted by Bankoletti:
The point of this thread however is not "F6F vs Zero in IL-2 simulation", it's rather "F6F in IL-2 simulation vs F6F in reality". Or any other plane for that matter, the thread appears to revolve about this example (F6F vs A6M). Or more accurately: "Energy bleed during high speed maneuvering in IL-2 vs the same in reality". To bring the whole question to a point; Yes! The planes in Il2 behave exactly as in reality or close to, the FW in IL2 is just good - OUT http://forums.ubi.com/images/smilies/crackwhip.gif



<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by freakvollder:
The difference in wing-size is not significant. At the same AOA the spits-wing create much more LIFT but not that much more drag. It is simpler as you might think --> wing-loading is the deciding factor nothing else. The spitfire-wing is not a magic RAF secret http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

Originally posted by Bankoletti:
Sorry but that's completely wrong. We are not speaking about parasitic drag, but induced one. Induced drag is proportional to the wing area (and to the density of air and to the square of TAS - in the most simple form). </div></BLOCKQUOTE>In this example we have nearly equally fighters: In this case the wing size does not really matters, but the AOA does! http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif

freakvollder
11-30-2010, 03:37 AM
Originally posted by freakvollder:
completely nonsense but I hope you know that already http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif Buzzsaw- I want to apologize me for these stupid words I've used http://forums.ubi.com/images/smilies/blush.gif after reading it again I find is was not the right way.

S

M_Gunz
11-30-2010, 05:07 AM
It's funny how one fact can be used to build a ladder of abstraction that has little to do with reality.

------------------------------------------------------------------------------------------------------------

NASA, history of flight. (http://www.hq.nasa.gov/pao/History/SP-468/ch1.htm)


The zero-lift drag coefficient CD,O is a nondimensional number that relates the zero-lift drag of the aircraft, in pounds, to its size and the speed and altitude at which it is flying. Generally speaking, the smaller the value of this number, the more aerodynamically clean the aircraft. For example, the value Of CD,O for the North American P-51 "Mustang" fighter of World War II fame is about 0.0161 (table III) as compared with about 0.0771 for the Fokker E-III fighter of World War I (table I). Accordingly, the P-51 is a much cleaner aircraft than the Fokker E-III.

Looking at table I, the P-51 shows 0.0163. P-38 shows 0.0268, F6F-3 shows 0.0211.

Now here's the FUN PART. Lift to Drag when your Drag is LOW doesn't mean MORE LIFT. It means LESS LIFT. You get MORE LIFT when you have MORE DRAG. That's how ratios work.

For the SAME DRAG as the Hellcat, the P-51 does have more lift BUT flying level, the P-51 has LESS DRAG so the ASSUMPTION that the lift is high is just a bit cracked. You need to know the weight of the plane and the AOA as trimmed.

You can't say how great the lift is based on L/D and in general THICK WINGS MAKE MORE LIFT +AND+ EVEN MORE DRAG.
L/D coefficient alone does not determine lift!

-----------------------------------------------------------------------------------------------------------------

1 G flight is straight and level or straight and constant rate of ascent or descent or an accelerating descent in combination with turn. The 1 G is about wing loading. The wings are loaded to 1 G in straight and level, etc. If you turn the plane and maintain height then your wing loading MUST be more than 1 G. G's in turn is not just about force towards the center of the turn. This is also why 1 G stall is not determined while losing height and that's not "just theory", it is FAA law.

JtD
11-30-2010, 08:19 AM
Originally posted by Bankoletti:
I'd love to see anyone in an F6F try to maneouver with a well flown Zero tailing him, and succsessfuly outmaneouvering and shooting him down - at any speed (of course without diving away, outclimbing and coming back in a good ol' BnZ attack). Result of a heap of luck - yes. Consistently? Show me. Words are useless.

It's pretty easy against AI. But then you said "well flown Zero", so I guess this doesn't count. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

Xiolablu3
11-30-2010, 12:14 PM
I know this doesnt factor in to the F6F vs Zero debate, but dont wing slats/slots also have an effect in this area? (meaning just wing loading is very misleading if said aircraft is so equipped)

Kurfurst__
11-30-2010, 01:02 PM
Slats/slots permit the wing to reach high angle of attack without stalling. Higher angle of attack = higher lift, but also higher drag.. ultimately it depends on whether the aircraft has enough thrust/engine power to overcome that extra drag. If it does, it can pull more Gs and turn faster without loosing speed. If it doesn't, it can turn faster for some time w/o stalling but it will quickly bleed off speed (drag>thrust) and soon slow down its turn rate, unless the pilot eases back on the stick.

Best sustained turn is where the most Gs could be pulled without slowing down. Since drag has two components, induced drag (depending on AoA) and parasitic drag (depending on air resistance, increasing w. airspeed), there is an optimum speed for it.

Bremspropeller
11-30-2010, 01:09 PM
t generates less drag at low G than a more conventional wing, and therefore generates more lift at low G's and the better lift allows it to turn better.

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


@ Xio:

Yes, technically, they do, but that's not what they're supposed to do (function-wise).
They're there to energize the boundary-layer, thus delaying it's disattachment for a couple of degrees more.

They're changing CLmax and attainable AoAmax to higher values.

M_Gunz
11-30-2010, 01:11 PM
Originally posted by Xiolablu3:
I know this doesnt factor in to the F6F vs Zero debate, but dont wing slats/slots also have an effect in this area? (meaning just wing loading is very misleading if said aircraft is so equipped)

They can pull more AOA but as I was shown by Brems http://forums.ubi.com/images/smilies/34.gif , it's the same lift slope after slats extend as before. So what you get is increasing lift until stall the same as without slats. With or without slats your lift and drag increase right up to stall angle though... the more rounded the top of the lift curve, the less extra lift per degree AOA you get before the stall which is not a bad thing in that you have some warning through tailing-off performance before stall. Not watching for that`is where a lot of players pull themselves right into heavy bleed without knowing it. You got to watch speed and turn rate and loosen up on the stick when they trend downwards, especially the turn rate, ie nose coming around.

Still to me, I see in a 109 a plane that without slats can't make enough lift to stay in flight down to reasonable landing speed. The lift curve and coefficient only apply to how much wing you have and that must apply against your weight. As freakvollider shows, the wing loading is critical. You want the extra lift, you have to take the extra drag as well. Smaller wings are less draggy than same wing only bigger and then there's width to length and surface finish just to make that no simple rule of thumb, now we have span loading and MORE... it's almost like nature doesn't want simple solutions.

Xiolablu3
11-30-2010, 01:33 PM
Thanks for all your replies.

I find slats/slots a very interesting subject. IIRC most modern jets utilise them in some way? SO they were obviously the way forward for some aircraft designs.

M_Gunz
11-30-2010, 02:29 PM
OTOH: I'd hate to be in a 109 that had battle damage to the slat on one side. I'd hope to find out before getting low and slow and have a chance to become a parachute tester instead.

Bremspropeller
11-30-2010, 02:34 PM
Fast, flat approach will do the job http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

@ Xio:

Yes and no.
Most modern jets (fighters) do have leading-edge devices, but due to different aerodynamics, their functioning is different.

Airliners do have leading-edge slats much similar (yet still different in the way they operate) to the HP-slats.

freakvollder
12-01-2010, 05:16 AM
The Messerschmitt engineers chose very small wings; they goal was to minimise drag at high speeds; but this small wings can't produce enough lift at slower speeds, which was the reason to put leading edge slats on it to increase the flying safety. That was certainly a very straightforward solution for this time period (1935-40). The focke wulf engineers went the same way by developing the Fw190 in 1938, only 3years after the bf109. These wings were conventional high speed sections, which was certainly a good compromise for the needed speed-range.

It seems that the German engineers looked for speed in the first place and regard tight turning as not so important. We all feel this way when we fly a 109 or 190 in the game; the damn thing can not turn as good as the historical adversaries can do; later in the war the situation was more equal. Interestingly the british and american engineers looked for speed as well, but they build planes in a more conventional way, thus this plane had the abillity to turn really good. In the early stages of the war the allied planes were not as fast but they turned better at slow speeds.

As sayed above, later in the war the situation was mor equal. Planes like the P51, P47, Spitfire(late Marks) and Tempest, in the case we regard only the western front fighters, were not radical desighns. They were very conventional as well. We have relatively big wings, compared with the german fighters and in the result a not as high wing-loading in general. If one look at the weight in combat and compare this with the wing-area of the fighters, one will find a relatively low wing-loading in almost all cases. Despite developments like laminar-flow wings, they never went the same radical way.

That above are my own views; coments are wellcome! http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

S

BillSwagger
12-01-2010, 05:48 AM
Originally posted by freakvollder:
this small wings can't produce enough lift at slower speeds, which was the reason to put leading edge slats on it to increase the flying safety

It allowed for a better stall warning but i'm not sure it allowed for more safety. Most pilot comments indicate buffeting and mushy controls while maneuvering with the slats out at slower speeds. I wonder how much they improved turn performance, if at all, or if they just helped the pilot manage the stall behavior better.



We have relatively big wings, compared with the german fighters and in the result a not as high wing-loading in general. If one look at the weight in combat and compare this with the wing-area of the fighters, one will find a relatively low wing-loading in almost all cases.

I think thats why you find bigger disparities in vertical performance rather than horizontal when it comes to weight.
The size and shape of the wing can be very crucial in determining the best flight envelope and altitude to fly the plane.
Wing area can also be beneficial to lift in thinner air, places where smaller wings might not be as effective especially where engine performance suffers and the plane can no longer keep sufficient speed required to produce the same lift at lower altitudes.

I've also learned that drag because of weight becomes less a factor with increased speed, but generally weight is a consideration for climb and fuel economy.

M_Gunz
12-03-2010, 12:48 AM
Originally posted by BillSwagger:
Most pilot comments indicate buffeting and mushy controls while maneuvering with the slats out at slower speeds.

The slats come out for a few extra degrees of AOA only, are always out at the stall. So highlighted above you have a description of near stall behavior for most planes with or without slats.. on planes with slats of course the slats will be out! However that does not mean the moment the slats come out the behavior is buffeting and mushy, the buffets are stall buffets while the slats come out before buffets.
Trying to generalize all slats behavior by what happens at/near stall... could I say that since Spitfire has buffets and mush at/near stall that it is that way the rest of the time?

This is what happens when 'deciding' performance or handling by anecdote. The words of one set of conditions get stretched to cover other conditions as well. That is the act "filling in 'fackts'" whether the person doing it knows or more often honestly does not.

Here is context for the near future "I didn't say that" reply:



Posted Wed December 01 2010 04:48 Hide Post

quote:
Originally posted by freakvollder:
this small wings can't produce enough lift at slower speeds, which was the reason to put leading edge slats on it to increase the flying safety



It allowed for a better stall warning but i'm not sure it allowed for more safety. Most pilot comments indicate buffeting and mushy controls while maneuvering with the slats out at slower speeds. I wonder how much they improved turn performance, if at all, or if they just helped the pilot manage the stall behavior better.



The slats extend the usable AOA of the wings with ALL that implies. Please if you don't know the implications then don't go grab and misapply quotes, we have G for that!

BillSwagger
12-03-2010, 04:50 AM
You've misapplied the context of my statements, again http://forums.ubi.com/groupee_common/emoticons/icon_rolleyes.gif opposing an argument i was never making.

To keep it in context what i was responding to, the slats made it easier to manage stall behavior but it was not necessarily an improvement to safety.

I make no argument about the 109s turn radius, i only question how much more the slats improved turn. Surely, the slats weren't the equivalent of wing fairies that gave the 109 the slow speed turn ability of an early Zero.
It may have made more a difference in negating poor high speed stall characteristics but what it actually adds to the turn in terms of radius would be interesting to know.


Most pilot comments indicate buffeting and mushy controls while maneuvering with the slats out at slower speeds.

Those are stall characteristics but the reference(s) are more specific to that particular part of the flight envelope where the plane is flying at slow speed.
I'm mainly referring to the tests found on Kurfurst's site, and i wouldn't refer to them as entirely anecdotal.
What you take them for is your choice but please don't twist my words or make assumptions so that you can attack me in an argument outside the context of what was being talked about.

Stick to Math Gunz, i can tell English was not your strong suit.
http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Bill

M_Gunz
12-03-2010, 06:50 AM
Originally posted by BillSwagger:
You've misapplied the context of my statements, again http://forums.ubi.com/groupee_common/emoticons/icon_rolleyes.gif opposing an argument i was never making.

To keep it in context what i was responding to, the slats made it easier to manage stall behavior but it was not necessarily an improvement to safety.

I make no argument about the 109s turn radius, i only question how much more the slats improved turn. Surely, the slats weren't the equivalent of wing fairies that gave the 109 the slow speed turn ability of an early Zero.
It may have made more a difference in negating poor high speed stall characteristics but what it actually adds to the turn in terms of radius would be interesting to know.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Most pilot comments indicate buffeting and mushy controls while maneuvering with the slats out at slower speeds.

Those are stall characteristics but the reference(s) are more specific to that particular part of the flight envelope where the plane is flying at slow speed.
I'm mainly referring to the tests found on Kurfurst's site, and i wouldn't refer to them as entirely anecdotal.
What you take them for is your choice but please don't twist my words or make assumptions so that you can attack me in an argument outside the context of what was being talked about.

Stick to Math Gunz, i can tell English was not your strong suit.
http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Bill </div></BLOCKQUOTE>

Not my strong suit? LOL to YOU! have you learned the difference between 'there' and 'their' yet? How about 'your' and 'you're'? But you tell me that English is not my strong suit! You get things wrong from 2nd and 3rd grade!

I haven't twisted anything you wrote. And you STILL don't get it!


To keep it in context what i was responding to, the slats made it easier to manage stall behavior but it was not necessarily an improvement to safety.

I replied:
The slats come out for a few extra degrees of AOA only, are always out at the stall.
I replied:
The slats extend the usable AOA of the wings with ALL that implies.

And you still persist:
i only question how much more the slats improved turn

It may have made more a difference in negating poor high speed stall characteristics but what it actually adds to the turn in terms of radius would be interesting to know.


quote:
Most pilot comments indicate buffeting and mushy controls while maneuvering with the slats out at slower speeds.

Those are stall characteristics but the reference(s) are more specific to that particular part of the flight envelope where the plane is flying at slow speed.

The slats extend the usable AOA of the wings with ALL that implies.

The more AOA a wing can pull, the more lift -at speed- it can make. Turn is by Lift. More AOA allows for a tighter turn at the same speed. More AOA allows for a lower stall speed.

Slats IN, the 109 turns less tight than slats OUT (higher AOA) at the same speed. Spitfire without slats can pull to a certain AOA just as 109 with slats can pull AOA to its own limit.

Is that so complicated you have to wonder about magic fairies? Then perhaps you need magic fairies to explain LIFT as well because that is all it's about!

Go fast enough in a 109 and you can't pull enough AOA to get the slats out without exceeding your G limits. Go fast enough in a Spitfire and you can't reach stall AOA without exceeding your G limits either. So yes slats don't get to come out at high speed unless the pilot screws the pooch. And you don't pull full AOA on non-slats wings at high speed either.

Perhaps you should see a theme here, you can pull AOA up to stall and SLATS allow the AOA to be higher. That is what they do, and completely without good magic fairies or bad magic gremlins either. (Thank You for getting me straightened back out on that, Brems!)


Those are stall characteristics but the reference(s) are more specific to that particular part of the flight envelope where the plane is flying at slow speed.

1 G stall being the slowest the plane can fly straight and level, what plane is not like that near stall when there isn't capacity to pull enough more lift to maneuver quickly? GOING SLOW, what plane does not have the nose and AOA high?
BUT you also ask questions turns and tightness. These are done at higher speed even when near or at STALL AOA and wonder of wonders you get the buffets in turns near stall (not 1 G stall, but loaded stall which happens at the SAME AOA) in every well-designed WWII fighter. The SLATS do not make exception.

Please in that reference show where the poor handling begins as soon as the slats come out! Slats coming out are NOT the onset of stall or stall handling just because slats are out at/near stall. They are out BEFORE then.

BillSwagger
12-03-2010, 07:46 AM
http://forums.ubi.com/groupee_common/emoticons/icon_rolleyes.gif
Gunz i know what the slats do. I'm not arguing with you, geez.
I was just pondering how much more turn the slats actually give the plane.
Its not even your place to answer that, but its an area of focus i'm interested in. Spare me your antics and your eloquent prose.


Please in that reference show where the poor handling begins as soon as the slats come out! Slats coming out are NOT the onset of stall or stall handling just because slats are out at/near stall. They are out BEFORE then.
Typical back seat Gunz.
http://www.kurfurst.org/

You have the reference, read up my friend. I'm not gonna walk you through every detail.
To focus my point so you don't go grabbing at assumptions again, the low speed handling under 200kph was the area of the envelope described. The handling was said to be better above 250kph in regards to slats and turn.
Handling in this sense is said to be whats felt through controls, not that the plane was exhibiting bad flight characteristics, only that the controls were mushy and buffeting was experienced at speeds under 200kph.
One report actually describes it as "aileron snatch", a symptom of the slats deploying unevenly.

My guess would be that at lower speeds and with different angles of bank the slats don't come out as evenly as they might at higher speeds. The combination of slats opening and closing at disproportionate rates presented a marginalized handling characteristic at low speeds



Bill

M_Gunz
12-03-2010, 08:06 AM
I'll just leave you to try and wring every nuance out of all the reports you can cherry pick and then Kurfurst and Brems can maybe help you get your head back in daylight.

Find me any WWII fighter that has good crisp handling at 30% above stall speed please. 200 kph / 155 kph = 1.29.
One without slats of course, to show the difference.

Asymmetric slat deployment... not normal operation, check with Kurfurst first and then see if Hopp will tell you it really is. Gunther Rall when asked said no, but what did he ever know about every report or opinion written?

Nahhh, you're NOT looking for whatever you can find or insinuate to say that slats on 109's were not good. It's just my poor English!

BillSwagger
12-03-2010, 08:30 AM
Nahhh, you're NOT looking for whatever you can find or insinuate to say that slats on 109's were not good.
http://forums.ubi.com/images/smilies/blink.gif
I made no such claim.
You must still be bitter about the P-47 thread. http://forums.ubi.com/images/smilies/34.gif
Why quibble over subtle remarks and completely miss the main point of a post, never mind that it completely sidelines the thread.

To keep it in on topic, the slats made it easier to manage stall behavior but it was not necessarily an improvement to safety.
Why..........?
At lower speeds the slats presented unfavorable control characteristics.
If you did the homework you would know this Gunz. Its no bad reflection on me for what you willfully ignore.

I make no argument about the 109s turn radius, i only question how much more the slats improved turn.



Bill

M_Gunz
12-03-2010, 12:37 PM
Originally posted by BillSwagger:
To keep it in on topic, the slats made it easier to manage stall behavior but it was not necessarily an improvement to safety.
Why..........?
At lower speeds the slats presented unfavorable control characteristics.

And the Spitfire, P-47, and P-51 wings have twist to ease the stall behavior, the inner wing stalls before the outer wing and the ailerons are on the outer wing. 109 has slats on the outer wing so the inside wing stalls first. Two solutions to the same end, one allows smaller wings to produce very high lift for their size and the other is simpler. Both are acceptable and surprise, suprise, slats are still used today.

Could it be used in turns? That depends on the pilot.

Q: The plane it had these wing slats and you mentioned they pop open uneven?
A: Two meter slots on fore wings. The reason was to increase the lift during low speed take off and landing. To reduce the length of runway you need. In the air, if you make rough turns, just by gravity, the outer slot might get out. You can correct it immediately by release of stick, you know? Only little bit, psssssssht, its in, then its gone. You have to know that. And if you know it, you prevent it.
Q: Did you use this extra lift from the slats in combat?
A: Not at all. I mean, its also a matter of experience of the pilot, you know?

A pilot who wants to stay fast has no need of the extra AOA the slats. An experienced pilot makes smooth turns.

Deployment of one slat due to a rough turn does not characterize all or most normal operation.

Here are the magic words from a British pilot who spent how long in 109's?

The Me.109 pilot summed up his general impressions of the aircraft as a fighter in the following manner. "From all this dog-fighting I am certain that if the pilot of a Hurricane or Spitfire finds himself attacked by a Me.109 he can easily out-turn it, and can lose it straight away by doing any violent manoeuvre,; the Me.109 just cannot be made to do a really quick manceuvre because at high speeds the controls are much too heavy, and at low speeds the slats come out, causing the ailerons to snatch, followed by the aircraft stalling if the manoeuvre is done more rapidly. "

And Rall said: In the air, if you make rough turns, just by gravity, the outer slot might get out. You can correct it immediately by release of stick, you know? Only little bit, psssssssht, its in, then its gone. You have to know that. And if you know it, you prevent it.
...
I mean, its also a matter of experience of the pilot, you know? <<---- ... FULL CONTEXT ABOVE

You know what? There's British evaluation of the P-47 as well. Let's go by that next time you bring the P-47 up since you think so much of their testing of foreign aircraft.

Or perhaps pilots new to a plane with no formal training on it really do get the most out of it after a few hours?

You're selling Cherries, Bill. Go pick some more. It's a standard forum tactic.

K_Freddie
12-03-2010, 12:48 PM
Oh yeah! Page 4 and rolling, keep it up boys.. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

M_Gunz
12-03-2010, 01:15 PM
I'd rather see more on topic than a dead horse (long ago) bone hunt. Do you know how old the slats fight is just on this forum?
It was old, tired and beat to death before you signed up as Freddie!

K_Freddie
12-03-2010, 01:26 PM
This aka is my 3rd one on UBI.. I've been around a longggg time, a lot longer than my 3655 posts
http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

Edt: looking at it, I'd say somewhere around the same time as BC

M_Gunz
12-03-2010, 06:14 PM
I had one name-change, started maybe as late as Oct 2001.

2002-2003 were the really big years here.. The Oleg Years, because back then Oleg would post and reply in his Ready Room.
It's gotten a LOT more quite since then. And yet, the same old subjects rehashed as if they've never been discussed to death before. All those poor horses and for nothing!

Xiolablu3
12-04-2010, 01:39 AM
Reg Hallam, an experienced Bf109 modern display pilot loves the Bf109's slats :--

http://www.youtube.com/watch?v...ture=related#t=8m11s (http://www.youtube.com/watch?v=EgvfklVzYZo&feature=related#t=8m11s)

M_Gunz
12-04-2010, 09:27 AM
He says you don't get the snatch rolls that you do with some slat-using types.

Bremspropeller
12-04-2010, 10:36 AM
Getting the slats out asymmetrically means you're in an uncoordinated turn, which is just as dangerous on airplanes with slats as it's on aircraft without slats at slow speeds. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

M_Gunz
12-04-2010, 12:07 PM
Would that agree with Herr Rall's words about depending on the "experience of the pilot"?

Xiolablu3
12-04-2010, 01:04 PM
It clearly depends on the knowledge and skill of the pilot as to whether the slats are used in turns.


Reg obviously likes using the slats in hard manouvers and has no problems with them.

'very benign' 'very smooth'

M_Gunz
12-04-2010, 05:46 PM
Making wide high speed turns doesn't cost me too much speed in an FW or P-47. When your turns are made at high speed you can have a good deal of vertical variation in shallow zoom. Just hold speed to 400-450 kph and see how much turn you get.

Then ask yourself what could you do to make that more? Trim? Slip? Radiator? Engine? Prop? Joystick wobble/spiking? All check?

If you know your 1 G stall for how you fly by checking what you get, at twice that IAS you're safe to go 3 G's while your engine+prop cover most or all of the drag. But you want to be 3+ x 1 G stall and able to pull full unsustainable G's for short periods and the sustainable turns there are very wide compared to sustained stall turns at less than 2 x 1 G stall IAS, but the shallow climb rate is very good and the zooms are even more so.

All you got to do is watch your IAS and be able to realize when it's time to change tactics instead of pull more stick.

BillSwagger
12-04-2010, 06:49 PM
Originally posted by M_Gunz:
I'd rather see more on topic than a dead horse (long ago) bone hunt. Do you know how old the slats fight is just on this forum?
It was old, tired and beat to death before you signed up as Freddie!

i guess for me its not so much a dead horse, and i'm sure you're well read on the subject as most people who've been into aviation and simulators are. I think my comments were directed more at the original poster and not so much meant for making a case about slats and how well they improve turn performance.
If your like me, you read up on a plane or topic which raises more questions to read about.
I don't think it always needs to be beat over or drilled into peoples heads, if they were interested they could read the information themselves.


You're selling Cherries, Bill. Go pick some more.
actually, what i provide are watermelons.
The cherry pickers only need shake the tree to see what falls.
If you really want to look into a plane you have to give it a bit more effort than a casual browse over common sites.

There's British evaluation of the P-47 as well. Let's go by that next time you bring the P-47 up since you think so much of their testing of foreign aircraft.
lol...If the British were not so distracted by the sexiness of their Spitfires I'd be more inclined to take there evaluations of USAAF aircraft more seriously.
Most of them offer good comparisons, but i sometimes find them to be a bit loaded such as comparisons with the T-bolt II and the Tempest. The T-bolt was compared with out using water injection, which would slant the results a bit don't you think? Truth be told, British pilot doctrine didn't favor heavier war birds often supplied by the USAAF. Despite my opinions, i wouldn't completely ignore them because the information they do provide is still somewhat useful.


Bill





Bill