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Aviar
01-28-2010, 04:49 AM
We know that the power stall characteristics of the P-38 are modelled incorrectly in IL-2. To see a real-life demonstration, check out this video. The relevant portion begins at 9:15.

http://www.youtube.com/profile?user=airboyd#p/u/23/gq_2UmiCoJk

I was just wondering if anyone knows if Team Daidalos is planning on looking into this issue.


Aviar

AndyJWest
01-28-2010, 05:12 AM
We know that the power stall characteristics of the P-38 are modelled incorrectly in IL-2.

Actually, we don't. There seems to be something off about the single-engine torque characteristics, which I believe TD have acknowledged, and may look into at some point, given what has been posted on the Ubi forums in response to this issue.

The only other thing I know about the P-38 FM is that it attracts an inordinate amount of controversy. Whether this is due to a faulty FM, or to unrealistic expectations about the performance of the actual aircraft is open to question. I suspect that if it modelled the historical behaviour more accurately, there would be less demand for 'increased elevator response', 'better roll rate' etc, and more complaints that it was over-sensitive. I'm sure that the poor guys who had to fly it felt the same way, though a good few of them never had the opportunity to complain. It was a WWII aircraft, not a magic carpet. Like any other aircraft of the time, if you mishandled it, it would kill you. If you were unlucky it might kill you even if you got everything right. The IL-2 simulation is almost certainly not 100% correct, for this aircraft or any other. All the same, it is just a simulation. Be thankful.

Crumpp
01-31-2010, 06:58 PM
unrealistic expectations about the performance of the actual aircraft

That is 99% of it.

julian265
02-04-2010, 03:54 AM
^ Says someone who has flown IL2 once.

Sure, there's a fair amount of griping by new players about stalling and climbing, but there are plenty of legitimate gripes too. The 109K4 is almost unusable at high altitudes due to lack of elevator effectiveness (or excessive forces required) and the P38 shouldn't be experiencing elevator ineffectiveness below 10kft.

Crumpp
02-04-2010, 11:29 AM
^ Says someone who has flown IL2 once.

That is not true. I play your game in SEOW once a week for the past few weeks with one of our museum members.

99% of the gripes I read about stem from unrealistic expectations of the poster. It is not a dig that they have no experience outside of a game and a bookstore, just a fact. They read an anecdote and do not any real frame of reference to apply it. Therefore it becomes a blanket claim for a simplistic one size fits all mental model of how aircraft work.

What is even better is when they do this and are hostile about it! Nothing like hostility and ignorance on the internet to get yourself ignored. :)

JG27CaptStubing
02-04-2010, 03:26 PM
I would say generally speaking most of the guys playing IL2 don't have experience in any of the planes in the game...

IceFire
02-05-2010, 01:07 AM
I would say generally speaking most of the guys playing IL2 don't have experience in any of the planes in the game...
Some of us know that and some others don't :)

It's true...there are many unrealistic expectations made out of historical propaganda passed down through books and TV shows and the like. We all know them so I won't mention any of them :) Those turn in to legitimate beliefs and they are sometimes crushed when they meet IL-2 which tried to do reality as best as they could with a 2001 PC (plus some upgrades since then).

The P-38 does have a funny stall sometimes and some FM bugs... it isn't a super aircraft (nothing is)... it is just an aircraft and the game doesn't simulate it perfectly. Improvements would be great for all aircraft but I and many others are realistic about what is possible and hope for more in the future.

Crumpp
02-05-2010, 03:13 AM
I would say generally speaking most of the guys playing IL2 don't have experience in any of the planes in the game...

Don't have experience in any airplanes, in the game or otherwise. If they did they would know it is not lift, thrust, or drag that makes an airplane fly. The airplane flies on money.

:P

they meet IL-2 which tried to do reality as best as they could with a 2001 PC (plus some upgrades since then).

For a PC game it is not bad at all. Most importantly, It is fun.

Aviar
02-06-2010, 04:29 PM
Here is another real life video concerning the P-38 stall characteristics, basically confirming the first video I posted. You can jump forward to 04:50 (4 minutes, 50 seconds) to see the pilot demonstrate that the P-38 does not 'flip over' in a stall....it simply drops it's nose straight down until the speed increases.

http://www.youtube.com/watch?v=RVsRKNzZmGM&feature=related


Aviar

AndyJWest
02-06-2010, 04:50 PM
As far as I can tell, in an unaccelerated stall, the IL-2 P-38 has no tendency to 'flip over' if you keep it straight: This is stick full back, sinking like a stone, but staying level:
http://i958.photobucket.com/albums/ae65/ajv00987k/P-38stall.jpg
In an accelerated stall (a tight turn for instance), it will 'flip' if you pull really hard, but there is ample warning from buffeting.

I doubt if a modern pilot flying a P-38 would treat it sufficiently roughly to make it 'flip', at least intentionally.

Viking
02-06-2010, 10:01 PM
http://en.wikipedia.org/wiki/Thomas_McGuire

He sure flipped!

Regards

Viking

Crumpp
02-07-2010, 02:48 AM
the pilot demonstrate that the P-38 does not 'flip over' in a stall.

Most airplanes don't "flip Over" in a stall either.


As far as I can tell, in an unaccelerated stall, the IL-2 P-38 has no tendency to 'flip over' if you keep it straight:

Exactly, that is normal too.

In an accelerated stall (a tight turn for instance), it will 'flip"

As it should....again normal.

Goes right back too:

unrealistic expectations about the performance of the actual aircraft


He sure flipped!

Exactly. He may have further aggravated it by applying asymmetrical power, a very dangerous and risky technique.

AndyJWest
02-07-2010, 03:23 AM
I suspect that part of the problem may be the way IL-2 allows some fairly horrendous instantaneous G-loads to be applied with some aircraft. Under those conditions, any asymmetric stall is going to produce an exaggerated rolling moment, which may indeed flip you inverted. A real-life pilot would be more aware of what was occurring, and less likely to stall in the first place. You also suffer from lack of peripheral vision, which would give you a better idea of your flightpath, and particularly changes in roll/yaw as you tighten the turn.

None of this is particular to the P-38, but given its benign handling up to the stall, it may be more liable to catch you out when it happens. Pulling a tight turn in a Fw-190 for instance, you need to use considerable rudder input to keep the ball centred, so you get used to the symptoms of it not being straight - I rarely actually look at the ball in tight turns, though I probably should. If it starts to yaw, you automatically correct with rudder, and ease off on the stick. With the P-38, turns are more or less coordinated without much rudder, so you get used to just pulling until you get the turn rate you desire - this is fine until you overdo it, because once it starts to go, the high polar inertia in roll and yaw makes immediate recovery unlikely. The real problem with the P-38 in IL-2 may not be anything to do with the FM at all, but instead due to the limitations of 'flying' from a PC. The only solutions I can offer for P-38 pilots are to (a) fly something else occasionally, just to remind yourself of how hard other planes can be, (b) when you have plenty of height, practice accelerated stalls until you can recognise the onset, and (c) shut off an engine occasionally, just to enjoy the sensation of flying something that will climb on one engine, and lands more easily like that than some single-engined planes do without the power deficiencies.

palidian
01-03-2012, 02:22 AM
I have to agree the P-38 is not modeled correctly.

The P 38 reacted slowly to the ailerons, but once it started rolling it rolled well. The P 38 should be able to turn inside a p 47.
I continually get out run buy what should be slower aircraft.
There was 750+ lbs of ammo on the nose, this affects the center of gravity.
The compressibility issue was fixed by the L model

WTE_Galway
01-03-2012, 04:01 AM
Some wartime interviews ... overall consensus would seem to be "the P38 does not stall easily but that does not make it a turn fighter". The interviews are worth reading in full.


Interview with MAJOR JOHN W. MITCHELL, USAAF in the Bureau of Aeronautics 18 June 1943

http://www.researcheratlarge.com/Aircraft/GuadalcanalP-38s/ (Page 6)

Q. For fighter airplanes, would you comment on the desirability of twin engines versus single engines?

A. I've flown twin engine planes only a couple of hundred hours; but I like them much better than single engine, especially in that over-the-water fighting, because if one engine is damaged you can come back on the other. That is the main advantage. Stability in maneuvering is also important - you can pull up and slow down, do a loop and get out in zero miles an hour; and it will just mush down a little, come around and pull down and out. There's no tendency to spin. The P-38 is the most stable airplane I've flown. You can do aerobatics with it beautifully.




Interview with Joe Foss (US Medal of Honor), 26 April 1943, about the P38 ...

http://www.researcheratlarge.com/Aircraft/VMF-121/ (page 5)

Q. What was your impression of the P-38's?

A. The P-38 is really a good plane as an interceptor, above 20,000 feet. If you get notice that a bogey is coming in, and don't have much time, give it to the P-38's; they can really get up there. If it's above 20,000 feet they make their runs, go on out far enough to make a turn, and come back for another run, When the P-38's were sparring around with me, they would buzz way down below me, take a look, then go up through a hole in the clouds, take a short look around and come back down. They ran all around the sky while I was doing my best just to stay where I was.

Q. Was any attempt made to use them at the limit of their range?

A. They went clear up to Bougainville. They sent P-38's to fly cover on B-17's and on B-24's. There would be Zeros above them and below them would be more Zeros, float bi-planes and float Zeros, but their orders were to stay in formation with the bombers. If any of the enemy fighters made an attack, they'd just pull up, give a short burst, and the enemy fighter would pull right back up out of range. When they failed to do this one day, three of them were shot down. They went down below 20,000 feet to get some "easy meat", (these float bi-planes that can turn on a dime) - went down and tried to dogfight - that was the end of three P-38's.




Interview with CAPTAIN THOMAS G. LANPHIER, USAAF, Bureau of Aeronautics, 18 June 1943

http://www.researcheratlarge.com/Aircraft/GuadalcanalP-38s/ (Page 11)


One day about thirty Zero's came over the field. Fifteen Grummans, a few P-40's and six P-38's were up. The P-40's saw the Zeros come in and went after them; the Grummans didn't see the fight for about five minutes. The Zeros, up around 20,000 feet, had pulled us off to the side; and while we were fighting them, the Jap bombers sneaked in at about 500 feet and dropped their bombs, doing little materiel damage but killing a few men. The Grummans went after the bombers and left us six P-38's to fight the thirty Zeros, and we shot down seven. We lost two men. One followed a Zero, and at Cape Esperance over a hill about 3,000 feet high both planes went into a cloud and neither was seen to come out. The other boy went after two Zeros trying to get home; his belly tank was still on, and a Zero probably put a couple of incendiaries through it because he blew up. That's the only time I've seen an American plane blow up; it just went all to pieces. We lost two planes and got seven -- not very good since we had plenty of altitude.

If we spotted Zeros first, we had no trouble keeping up with them. If we saw each other at the sane time and on the same level, we could always climb with them; they can't climb any faster than we. We have the advantage of being able to launch a high speed climb of about 190 miles an hour. (On one mission Captain Lanphier indicated 200 miles an hour, climbing about 2200 feet a minute - about wide open). One of our best ways of getting away from the Japs was to pull up in a high speed climb. Of course, if they began to climb when we did, we'd get up at the same time; but we were usually so far away they couldn't shoot at us.

The P-38's never tried to tangle with the Japs at any altitude. We'd follow them from 30,000 feet to sea level, but never tried to fight them; couldn't possibly do it at any altitude, regardless of whether we used our flaps or not. (Those new flaps, incidentally, are a great help in turning). We can outrun the Zeros straight and level at any altitude, from sea level up.




Interview with MAJOR JOHN W. MITCHELL, USAAF in the Bureau of Aeronautics 18 June 1943

http://www.researcheratlarge.com/Aircraft/GuadalcanalP-38s/ (Page 3)

Q. What kind of tactics do you use in the P-38's against the Zeros?

A. Well, I had a four-plane section which had flown together for about a year, which is unusual for the Army. Each of us felt very responsible for the others; I was responsible for my wing man and he for me. We never had occasion to use any evasive maneuvers; we were never surprised from behind. We had planned that if we were completely surprised and had to get out in a hurry we would pull off in a dive and scissor the way naval aviators do in the dive, except we would endeavor to pull off sidewise and back. In an attack, my first two planes would go in formation.

Four Grummans, away beyond their altitude at 26,000 feet, were jumped by some Japs from above. We P-38's went in at 240-250 miles an hour indicated and had a lot of speed when we got up to the Jap planes. I got a direct hit at one; another pulled off to the side and followed me. I pulled away at full throttle, about 180-190 miles indicated. The Jap fell back and back, keeping at the same level but no longer shooting. When he turned around to leave, My wing man got him.

We try to stay in a ball within a mile area, each keeping his wing man in sight. The leader, being the ranking man, has first chance to shoot; and the wing man, although he also wants to shoot down enemy planes, suppresses that desire until the leader has taken care of his Jap. Then it's the wing man's chance, with the leader protecting him. We operate that way - just two fellows working together. It is the leader's responsibility, however, to keep the two pairs of planes in proximity to each other. Naval aviators are far better disciplined than Army, primarily because they've flown together longer.

Q. Is the high wing loading of the P-38 a handicap in combat?

A. It has a high wing loading on paper but not in the air. It won't stall because of the action of the two engines. You pull it right up; when it is time to stall, you look at the altimeter. You feel no sensation until it starts to drop. You can get right up steeply; if something is following you keep pulling up and up until it indicates zero, then start falling.

Q. You went head-on at the Zeros?

A. I only got two head-on passes. If the Zeros saw there was a chance of our getting around them, they'd turn and go off; we couldn't seem to get them to tangle with us. The P-38 is a very maneuverable plane, despite its size.

IceFire
01-03-2012, 04:24 AM
I have to agree the P-38 is not modeled correctly.

The P 38 reacted slowly to the ailerons, but once it started rolling it rolled well. The P 38 should be able to turn inside a p 47.
I continually get out run buy what should be slower aircraft.
There was 750+ lbs of ammo on the nose, this affects the center of gravity.
The compressibility issue was fixed by the L model
I can tell you with some degree of certainty that the P-38 can definitely turn inside of a P-47 and once you pop the combat flaps you can REALLY turn inside the P-47. In a stall fight you can compete with some versions of Bf109.

Which aircraft are out running you? The P-38J will run away from many 109 and some 190 variants depending on the year (especially in 1943) although occasionally acceleration is an issue. Most Japanese fighters don't stand a chance. Late war the P-38 isn't the fastest on the block anymore and you can't expect to outrun a MW50 boosted Bf109K-4.

I find the biggest "issue" for P-38 pilots is that they are often caught hauling loads of rockets and/or bombs and even when the ordinance is expended the leftover attachment points from that reduce the top speed significantly.

MrBaato
01-03-2012, 08:48 AM
I can tell you with some degree of certainty that the P-38 can definitely turn inside of a P-47 and once you pop the combat flaps you can REALLY turn inside the P-47. In a stall fight you can compete with some versions of Bf109.


I have to agree with this. In a stall fight it's very good and in medium speeds you can outturn alot of fighters by trimming it. IMO it's does good in a dogfight but it's still a heavy plane.

If you want to fly it with boosted performance, compete with any single engine fighter in a turn... play Aces High, made in the USA ;)

(oh and in the stall video's they didn't drop the speed to where the plane actually fell out of the sky, not really an eye opener.)

EJGr.Ost_Caspar
01-03-2012, 09:29 AM
As far as I can tell, in an unaccelerated stall, the IL-2 P-38 has no tendency to 'flip over' if you keep it straight: This is stick full back, sinking like a stone, but staying level:

Indeed. And if you do not use elevator in an climb with idle power, it just will nose down at stall.ing It's exactly what I see in the vids.

palidian
01-03-2012, 01:44 PM
Playing online, A 109g2 and a jack were chasing me, the 109 could keep up and the jack gained ground. In addition, most of the late war Russian stuff as the La 5 will out run a p38L.

In Il2 the p38 is stable, and hard to stall.

There still is the rolling issue, the ammo center of gravity issue, and the compressibility issue.

Luno13
01-03-2012, 07:30 PM
Indeed. And if you do not use elevator in an climb with idle power, it just will nose down at stall.ing It's exactly what I see in the vids.

+1

What a lot of people don't seem to realize is that in Il-2, the stall is occuring much before the blue "Stall!" warning appears. It's possible to completely stall aircraft without that blue message appearing at all. As such, it's quite useless, except to explain to the noob why he's suddenly corkscrewing uncontrollably and why pulling up more doesn't help.

The P-38 is very docile in game, and only spins out if you really try.

PS - it's important to note that 2 inches back on your joystick is probably equivalent to 40 lbs of force on the real thing ;)

EAF331 Starfire
01-04-2012, 11:37 AM
Quote:
unrealistic expectations about the performance of the actual aircraft

That is 99% of it.

Like people complaining about the warwinning P-51's turnrate :rolleyes:

IceFire
01-04-2012, 09:26 PM
Playing online, A 109g2 and a jack were chasing me, the 109 could keep up and the jack gained ground. In addition, most of the late war Russian stuff as the La 5 will out run a p38L.

In Il2 the p38 is stable, and hard to stall.

There still is the rolling issue, the ammo center of gravity issue, and the compressibility issue.

None of that is surprising. The 109G-2 is a very fast fighter and the J2M3 is also a very fast fighter. The late war Russian aircraft are also extremely fast but only at very low altitudes. Take that La-5FN up to approximately 10,000 feet or higher and the P-38L Late (with high boost) gets faster and faster while the La-5FN drops right off.

WTE_Galway
01-04-2012, 09:59 PM
None of that is surprising. The 109G-2 is a very fast fighter and the J2M3 is also a very fast fighter. The late war Russian aircraft are also extremely fast but only at very low altitudes. Take that La-5FN up to approximately 10,000 feet or higher and the P-38L Late (with high boost) gets faster and faster while the La-5FN drops right off.

All true ...

But now imagine a P38 with a pair of Griffon 65's running 21psi and 150 octane gas :D

Luno13
01-05-2012, 06:12 PM
It would probably be too nose-heavy, unless the booms were extended. Interesting concept though.

To underscore what IceFire said: The P-38 was less successful in Europe as it was over Africa and the Pacific. The Jack was a relatively rare fighter, with only several hundred produced, and most flew bomber interception sorties. The late-war Russian stuff was light and fast (even Kozhedub is reported to have shot down two Mustangs which attacked him in his Lavochkin). The lightning was fast, but not faster than the late-war stuff on that list.

If flown well, it is a good fighter, but the P-38 really wasn't a "magic carpet".

If the development of the design hadn't been so protracted, it could have been a truly great plane.

JtD
01-06-2012, 05:44 AM
I think it was anyway.

palidian
01-06-2012, 03:29 PM
Airplanes have a center of gravity, some components are fixed, and never change the center of gravity, as the engine, others are expendable, as fuel. Aircraft designers, attempt to keep the expendables in the center of gravity so the plane does not change its flight characteristics. The two worst US aircraft, were the P51, and P38, the P51 had to use the 85 gallon tank up first, to make the plane fly normal, the P38 had the weapons way out front, making for a severe center of gravity change. Most planes place the ammo, and fuel in the wings, so expending both will not change the center of gravity.

The p38 handled differently after it used up ammo.

EJGr.Ost_Caspar
01-06-2012, 07:29 PM
I think it was anyway.


For such an unconventional twin engine it's been fabulous!

EDIT: Not to forget: its beautifull!

http://upload.wikimedia.org/wikipedia/commons/4/48/P-38_Lightning_head-on.jpg

Xilon_x
01-06-2012, 07:39 PM
uaoooooo bellissima foto goog i like much much this photo whit sea.

Jumoschwanz
01-16-2012, 02:43 PM
Like people complaining about the warwinning P-51's turnrate :rolleyes:

The P-51 was not a "war-winner", the war was already won when it came into use in any numbers at the beginning of 1944. By this time the large part of the Luftwaffe's aircraft and best pilots were gone, not to mention that Germany was a small country with very limited resources and never had anywhere near the number of aircraft that the allies had.

The P-51 did well when it finally did get to the war because of these factors, and because it was supported by a wingman and it's squadron. A lone pilot in a P-51 did not fly over the channel and start shooting down "Gerries" right and left.

Chuck Yeager said in his book that pilot with the most experience will always win, no matter what they were flying, and by 1944 Germany was out of experience pilots....

Thinking the P-51 was a war-winner is Fanboy talk...

EJGr.Ost_Caspar
01-16-2012, 03:05 PM
It was nethertheless a plane with very good performance for its time and - much more important - able to escort the bomber formations to their target and back.

K_Freddie
01-16-2012, 08:25 PM
As Goering commented ... in Berlin ;)

The P38 is a fast hit and run (strike) aircraft.. fly it within it's limits and advantages and she'll 'service' you well.
It can also take a fair amount of damage and get you home.
:)