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View Full Version : Different speeds and flat turns.

M_Gunz
11-23-2010, 07:51 PM
At different speeds your plane may be able to pull limited G's in a flat turn, and may not be able to sustain those G's.

At 300 kph for example, most of these planes can pull 4 G's or less and can't maintain more than about 3 1/2 at sea level and less with increased altitude. Start of turn 300kph and 4 G's bleeds down to slower and less G's. Typical turn fighter?

You have this dynamic between speed and G's that gives the radius of the turn. Below some speed the plane will stall but at that speed it will turn the tightest radius for the G's applied. But the tightest 3 G turn, is that the tightest possible?

So here is the setup: Some other plane going faster than his lowest 6 G speed may be able to make a near equal or even tighter radius and will take time to bleed down to where he can't pull 6 G's... call it 'smash'.

And if you are in DF and see this happen where perhaps the known better turning plane is out-turned then hey what do you say?

K_Freddie
11-23-2010, 09:34 PM
You're Gaston in disguise.. aren't you ?? http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

M_Gunz
11-24-2010, 02:38 AM
Since when did G use anything that can be checked? This is about GEOMETRY and PHYSICS. Does G use those?

go check the light blue table about 60% of the way down (http://www.aerospaceweb.org/question/performance/q0146.shtml)

200 kts - 2 G's - 2050 ft
300 kts - 4 G's - 2060 ft

2x more G's at 50% more speed and almost the same radius.

The formulae are there if you can handle them. I'm just pointing out some implications that don't seem to get much consideration by a real segment of the forum who nevertheless like to play mix-and-match with unstated facts.

So how can a 109 out-turn a Spit? Perhaps by catching the Spit where it can't turn as hard, ie going too slow to turn hard. Anybody dumb enough to think that only applies to 109 vs Spit?

This isn't about FAIR turn performance comparisons. It's about showing where the falsehoods get thrown in.

BTW, one pilot who flew Black Six, a 109G-6, found the 1G clean stall to be about 155 kph. Double that is 310 kph and about there that plane should have been able to pull 4 G's at the stall edge.. and need to lose alt to keep it up.

Kettenhunde
11-25-2010, 10:36 PM
http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

M_Gunz
11-26-2010, 01:15 AM
And this is only FLAT turns. Add the vertical element and there is enough to show how energy fighting can result in kills very hard to avoid.

jameson2010
11-26-2010, 03:20 AM
er... 300 knots = 555.6 kph. So turning in a 109 at that speed with it's concrete elevators?

M_Gunz
11-26-2010, 10:31 AM
I wrote about kph which is kilometers per hour. Knots is kts, no per hour as that's part of the word knots.

jameson2010
11-26-2010, 12:01 PM
Oh ok. Then 310kph is too slow to be dogfighting in a 109, at that speed you are dogmeat. The expectation of coming across a spitfire flying at 200kph, well just about possible I 'spose but unlikely. And it makes a flat turn at that speed? I'd say that would be a fatal error wouldn't you.

TheGrunch
11-26-2010, 12:09 PM
You don't fly around at that speed hoping to find an enemy. What Gunz is saying is that that's around about the aircraft's best sustained turn speed. If you've got down to that speed it's all gone to hell anyway.

waffen-79
11-26-2010, 12:32 PM
Hi!

are you guys flying spits or early russian birds?

why you need to perform flat turns?

M_Gunz
11-26-2010, 04:46 PM
Originally posted by jameson2010:
Oh ok. Then 310kph is too slow to be dogfighting in a 109, at that speed you are dogmeat. The expectation of coming across a spitfire flying at 200kph, well just about possible I 'spose but unlikely. And it makes a flat turn at that speed? I'd say that would be a fatal error wouldn't you.

Oh that Chart shows knots! I only used it to show how the matched turns are possible by geometry without using math Here.

Sorry but I thought when you wrote 300 knots that you meant my words about 300 kph able to pull about 4 G's, not the chart.

And really, 109 stick wasn't that hard below level maximum speed anyway, not concrete.

M_Gunz
11-26-2010, 05:00 PM
Originally posted by waffen-79:
Hi!

are you guys flying spits or early russian birds?

why you need to perform flat turns?

You shouldn't. I try to get around to that from constant forum battles over what? Oh yes, flat turn performance! And what kind of 'evidence' is used and abused so much? Oh yes, combat reports! Will I mention names? No. Only that someone keeps using combat reports to tell of FW 190 as a great low speed turning plane.

What good is flat turn performance? Exactly to tell one part the useful agility of an airframe with sustained flat turn telling about ability to hold/replace energy in maneuver. Those apply to other maneuvers than turn, you know? But hard flat turn *for combat* is wasteful of energy and only has place some times, such as to bring a quick end to the target 20 degrees to the side.

M_Gunz
11-26-2010, 05:14 PM
Originally posted by jameson2010:
Oh ok. Then 310kph is too slow to be dogfighting in a 109, at that speed you are dogmeat. The expectation of coming across a spitfire flying at 200kph, well just about possible I 'spose but unlikely. And it makes a flat turn at that speed? I'd say that would be a fatal error wouldn't you.

Around 310 the 109 can pull about 4 G's. Spit can pull 4 at just a little slower IIRC because slightly lower stall. And neither one can maintain a 4 G turn.

Point is that someone moving fast enough to pull 6 G's with enough extra to maintain 6 before bleeding down too slow is not at a disadvantage.. but I think you already know this.

It is about Energy For Angles and how with energy to spend a "lesser turning" plane has not lesser outcome. Same coin: It is about observations of one plane turning inside another does not always mean the one inside has the better equal condition turn performance.

IAS 300 kph in combat, IMO you'd better be awfully high up unless you like being an easy target.

M_Gunz
11-26-2010, 05:17 PM
Originally posted by TheGrunch:
You don't fly around at that speed hoping to find an enemy. What Gunz is saying is that that's around about the aircraft's best sustained turn speed. If you've got down to that speed it's all gone to hell anyway.

Another who knows well. Yet we have the circle fighters and worse yet, flap-circle fighters.

Wildnoob
11-26-2010, 06:32 PM
Hauptmann Heinz Lange, an ace with 70 victories said:

"I believe the Fw 190 was more manoeuvrable than the Messerschmitt — although the latter could make a tighter horizontal turn, if you master the Fw 190 you could pull a lot of Gs [g force] and do just about as well. In terms of control and feel, the 109 was heavier on the stick."

Source: Osprey Fw 190 Aces of the EF.

At least with the Fw 190 A in IL2, we have much less acceleration as it had in rl as far as I know. Also about his comment of the 109 being heavy at stick, it's interesting to see how pull hard manuvers was tiresome. That's why I defend a stamina bar.

jameson2010
11-26-2010, 07:16 PM
Gunz, I do not disagree with the logic of your argument just the point of it. The better I get at flying in this game the less I want to pull any more than 1g.

Ideally, the best 109 attack is at 550 to 600 kph descending rapidly out of the sun in a long arcing turn below and behind the target, climbing back up in his blind spot and stabbing him in the underbelly and leaving him to bleed to death if he isn't dead already.

Turning at 6g you've blacked out or on the verge of doing so, so sustaining such a turn is a moot point given in a 109 you'd also be burning speed like no tommorow, which is what it would be if he's got a wing man nearby. I don't know if anything in the game can sustain 6G in a turn. G. Wellum claimed he went out like a light at 5g in his Spitfire, and did so everyday!

Point is, given your scenario there are much better methods of attack which retain speed, climbing say, then rolling over and down into the target pulling less g and possibly gaining speed on the descent. Your info is interesting but not exactly practical given 'speed is life'.

I hope Gaston is feeling well, I thought he'd be along by now, he wonky propeller theory would be great if it worked!

regards

M_Gunz
11-26-2010, 09:30 PM
My methods of attack are not through prolonged hard maneuvers. I'd rather cross someone's circle/arc and hit them from deflection than think of following their path. I know how to run a lower energy path just fine, have for many years.

I thought that I made it clear what I started this thread for. I guess I hadn't.

jameson2010
11-27-2010, 04:48 AM
Gunz, I wouldn't dare to suggest that your methods of attack are less than perfection, but as you are a leading light on the forum, and therefore is assumed to know what he's on about, this thread could be construed as a bit confusing for the average nugget.
Sacrificing speed for position, i.e. energy for angles is valid under some circumstances but a bit of a one shot wonder in your scenario as both wind up in a tight flat circle, attacker still unable to pull lead enough to get a shot.

To fly 109's fast they need to have trim adjusted nose down somewhat which makes the elevators even less effective than they are modelled ingame at 500kph, so I'm still nosing in on occasion wondering what's happening!

What we all need is a 'no energy for angles' attack, bit like Gaston's only a shade more realistic. Something for you to get your teeth into.

All the best...

M_Gunz
11-27-2010, 07:03 AM
I never claimed perfection but once I was pretty damned good and did learn a lot. Even got a copy of Shaw's book and read all the non-missile parts back in the late 90's. Some I learned from had been Air Force fighter pilots IRL and many were just damned good and then some. What I try to discuss here is so far beneath perfection I don't worry much about measuring up.

I've been trying to explain about how a difference in speed can make one plane able to turn inside another even though both at the same speed as the slower one, it could not.

This applies to combat reports, especially those that don't give the speeds of both planes. Hence I can read about 109's turning inside Spitfires during the BoB and understand how that can happen which BTW can also be from power at alt difference and just pilot experience too. Funny though, I don't see it as 109's inherently turning faster under equal conditions at speeds between 240 and 300 kph.

It also applies in-game and there I think that the nuggets would benefit knowing how it can happen.

I'm a big believer in using the vertical to control my speed and store energy at the same time. Yoyo's and barrels are some of my favorite moves. I don't like diving too far to make a strike, 150kph closing speed is about the most I usually want and I tend to start shooting from 300-400m as very soon after I'll be working my exit strategy as I had learned from reading Hartmann quotes. But I very rarely ever was able to shoot from as close as he did in any WWII sim without ramming as well, so no.. I'm far from perfect.

Tell you what. Why don't you start a thread on the style you find works best?

M_Gunz
11-27-2010, 07:12 AM
Originally posted by jameson2010:
What we all need is a 'no energy for angles' attack,

I'd rather cross someone's circle/arc and hit them from deflection than think of following their path. I know how to run a lower energy path just fine,

That's a subject in itself, flying a lower energy path than your target and shooting him at the crossings.

You can beat a faster plane that way if the other pilot just cooperates by jinking, turning and staying on the flat. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

There's at least 4 or 5 basics like that behind my old bag of tricks and I never knew all the good ones. I'm sure of that because of the people online that would do things to me I never figured out!

freakvollder
11-28-2010, 09:58 AM
My view of tuning is this:
The tightest turn with the fastest rate starts allways from corner-speed and goes down to the maximum sustainable speed(the Il2-Compare-value)
For example a 109 starts at corner around 450 kph(all speeds are IAS), next the pilot pull the stick close to black-out until he reach around 330kph and than he stays there.
That is the best turn you will get with the tightest radius and the highest turn-rate!

starting a turn at the Il2Compare sustained turn speed, which in the case of the 109 example is around 330kph, you will only get slower, because it is very hard to stay at 330kph all the time. Your turn will really get worse! The radius will be smaller but the rate decrease also! And that's worse.

S

M_Gunz
11-28-2010, 01:31 PM
I guess that the speeds depend on which 109 you are flying. Best sustained turn for these WWII fighters is less than 4 G at IAS less than twice 1 G stall. A very powerful fighter might sustain 3.5 G but only at low altitude, and less than 3 G up high, high being for the plane and not absolute X meters alt = high.

What 109 has 1 G stall at half of 330 kph, 165 kph? Most G models stall about 155. I think it's very good practice to keep a speed margin, stay above the stall, but the best turn rate that can be done is without that margin. 3.5 G requires about 1.9 times 1 G stall btw. Perhaps the 109K-4 has stall around 170 kph or more? I would be surprised so surprise me!

freakvollder
11-29-2010, 11:08 AM
I think 109k stalls also at 155kph(IAS) but I don't know it exactly.
I realy don't know much about specific G numbers and turning circumstances.
I try to turn as less than possible http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

S

M_Gunz
11-29-2010, 02:34 PM
I'd rather keep the speed up anyway. If I need to slow down in a turn then I zoom a bit to do it and turn 20 or 30 degrees using the vertical, then drop and make another bit of turn, wash, rinse, repeat ala yoyo.

However I wanted to start out with the flat turn case just to cut down on variables and show things about mixed turns at different speeds and g-loads, and that is all for this thread. If I can cut out some of the seeming mysteries and paradoxes then I've done well IMO.

freakvollder
11-30-2010, 03:54 AM
could it be that it is so simply that one can say: the more speed an aircraft has the more lift it can produce and because of that It can turn faster/better? Surly up to a point the airframe and or the pilot can stand it(blackout/wingboke etc.)

S

M_Gunz
11-30-2010, 04:36 AM
Yup. Most WWII docs I've seen put the limit at 6 G's because of the pilot. Modern military chart I've seen goes to 9 G. For very short times more can be stood, the Red Bull pilots show going to 10 and 11 in over the top loops.

Shaw also covers this and he says pretty much what you did. You have lift limits, airframe limits and pilot limits. With these fighters the pilot is the weak link.

BTW, available lift is by speed squared. Twice as fast allows 4x the lift. That's why I like to use 4 G's as an example, the square root of 4 is nice and clean 2. Square root of 6 is like 2.45 so I say a bit less than 2.5. That's 2 extra G's for less than +1/2 extra speed!