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ZG77_Nagual
10-26-2004, 09:45 AM
I was hoping for a tweak to this bird's fm in PF but alas - she has a twitchier stall than many planes in the simm - and I still the the low speed turn is off.

That said - PF is fantastic! The new navy planes are great and the improved graphics are fab and do not seem to overly tax my system. Hat's off to Maddox for some superb work!

Philipscdrw
10-26-2004, 10:15 AM
Why do you need 2 threads to talk about the P-38 handling?

NN_EnigmuS
10-26-2004, 10:49 AM
sorry but i not agree here

never flown that much p38 in aep game but last time in aep+Pf i easily destroye online a bf109g6 with mk108 on noise in a dogfight

in using flaps the plane is a very capable aircraft and quite fast even on deck

p1ngu666
10-26-2004, 11:54 AM
enigus, the p38 should have stall similer a j8a, be very stable at all speeds

Korolov
10-26-2004, 02:09 PM
*sigh* Pingu, for the last time, the stall speed of the P-38 with flaps and gear down was 70mph. Go any lower than that, and it will snap over. Capice?

SeaFireLIV
10-26-2004, 02:32 PM
Korolov speaks truth.

crazyivan1970
10-26-2004, 04:12 PM
The tribe has spoken http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

p1ngu666
10-26-2004, 04:18 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Korolov:
*sigh* Pingu, for the last time, the stall speed of the P-38 with flaps and gear down was 70mph. Go any lower than that, and it will snap over. Capice? <HR></BLOCKQUOTE>

you is wrong
it should mush, not snap over http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif

actully, its prolly more mush than snap over for most planes, but a mix between the 2

theres nothing on the p38 to make it roll over onto its back, UNLESS its on 1 engine i guess, or damaged. that was a problem with the mossie. the single engine safty speed was highish, so u could get to a speed on landing where u no longer had rudder control, or ran out of rudder and it would roll into the ground http://forums.ubi.com/images/smilies/16x16_smiley-sad.gif

so the speed is correct, the effect isnt, thats my beef.

IIJG69_Kartofe
10-26-2004, 04:24 PM
Stop talking about P38 stall like J8A or ... http://www.derui.easynet.be/santa/fasching.jpg

ImpStarDuece
10-26-2004, 06:24 PM
The abve picture scares and disturbs me.

This kid is a prime candidate for couneselling.

Haloween is the WIERDEST holiday ever, and i live in a country which has a national festival revolving around gettin draft horses drunk!

p1ngu666
10-26-2004, 06:55 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by IIJG69_Kartofe:
Stop talking about P38 stall like J8A or ... http://www.derui.easynet.be/santa/fasching.jpg <HR></BLOCKQUOTE>

your right, it shouldnt drop a wing, but should remain pretty much level.

thankyou for correcting to me to a more right status http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

and yes, the pic is sick, i doubt the kid even knows why suicide bombers do what they do.

Korolov
10-26-2004, 07:11 PM
So, let me ask you this, Pingu:

Have you ever flown a P-38 before?

I didn't think so. The fact is that the P-38 is prone to wing-overs just as much as any other plane. The difference is it's onset of a wing over is more limited than single engine prop planes, but it can happen to it all the same. All it takes is one wing to get more lift than the other...

BigKahuna_GS
10-26-2004, 11:43 PM
S!

From all that I have read about the P38 was that when it stalled it simply mushed forward. That is how 38 drivers were able to perform the "cloverleaf maneuver".

"The cloverleaf was a horizontal maneuver that took advantage of the P-38's
exceptionally gentle stall characteristics. It was a low-speed maneuver. The pilot would tighten his turn until he actually stalled out, ease off and let the plane unstall itself, then tighten back up into a stall, ease up....

Viewed from above, the pattern the airplane flew through the air looked something like a cloverleaf, and this simply was used in teaching the maneuver."



To be honest one of the P38's largest problem is the fact that it is stalling at about 88mph with flaps and gear down, no matter how lightly loaded you are.

Here is the raw data:

Vs1 (clean) 94 mhp; 100 mph and 105 mph
Vs0 (dirty) 69 mph; 74 mph; and 78 mph

The three weights are 15, 17 and 19,000 lbs.

88 seems WIDE of the mark. Is 88 the ias when it stalls? I can read my gauges and fly at the same time.

Stall is described in the POH: "As stalling speed is approached, the center section stalls first with noticeable shaking of the airplane, however, the ailerons remain effective.

"In either power-on or power off stalls with flaps and landing gear up, the airplane mushes straight forward in a well controlled stall. With flaps and landing gear down, there appears to be a slight tendency for one wing to drop. There is, however, no tendency to spin. Under these conditions, the nose drops slightly and as the speed increase the wing will come up." [emphasis mine]

Of course, all AC stall from the center section as the angle of incidence is tapered to allow for continued maneuverability into the stall from the ailerons. The real difference is its forward motion in a stall!



Thought this was interesting :

WWII: Of all the Allied fighters you encountered, which was the most
difficult to handle with a good pilot at the controls?

Steinhoff: The Lightning. It was fast, low profiled and a fantastic fighter, and a real danger when it was above you. It was only vulnerable if you were behind it, a little below and closing fast, or turning into it, but on the attack it was a tremendous aircraft. One shot me down from long range in 1944. That would be the one, although the P-51 [Mustang] was deadly because of the long range, and it could cover any air base in Europe. This made things difficult, especially later when flying the jets.


Here's an excerpt of a Luftwaffe experte's (Heinz Knoke, 52 kills, all in
the West) description of a duel with a P-38 (from "I Flew for the Fuhrer"):

"...At once I peel off and dive into the Lightnings below. They spot us
and swing round towards us to meet the attack.... Then we are in a madly
milling dogfight...it is a case of every man for himself. I remain on the
tail of a Lightning for several minutes. It flies like the devil himself,
turning, diving, and climbing almost like a rocket. I am never able to
fire more than a few pot-shots...."


____

VFA-195 Snacky
10-27-2004, 02:43 AM
Korolov as far as Pingu flying a P38 goes neither have you my friend nor has anyone here, I usually agree with you on things related to the lightning, but in this case you are wrong. I suggest you go to Zenos and watch the official USAAF P38 training film and listen to the section on low speed stall for the P38. look at 9min 30sec on the video- "flaps up stall occurs at 70mph, counter rotating props eliminate torque, no tendancy of either wing to dip or pull away."
Along with this is footage of the pilot stalling the P38 and the aircraft nosing over, not doing a wing over or torque roll. This is not what Oleg likes to call "Propoganda", this was a training film used to train P38 pilots.
http://www.zenoswarbirdvideos.com/P38.html

To the parent of that child- You are a sick individual and that photo is not funny one bit. http://forums.ubi.com/groupee_common/emoticons/icon_mad.gif

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Korolov:
So, let me ask you this, Pingu:

Have you ever flown a P-38 before?

I didn't think so. The fact is that the P-38 is prone to wing-overs just as much as any other plane. The difference is it's onset of a wing over is more limited than single engine prop planes, but it can happen to it all the same. All it takes is one wing to get more lift than the other... <HR></BLOCKQUOTE>

JG77Von_Hess
10-27-2004, 03:44 AM
Well this problem isent only related to the P38,
the wing drop occurs to all planes.. Power on or power off, flaps or no flaps. Its related to the game engine, same goes for all planes are capable of doing fully crossed controles with-out entering a hazard! No need of stepping on it when your banking, turning you plane.

So in short if anything here should be changed it should be fundamental for the games flight physics..

Regards.

VH.

BigKahuna_GS
10-27-2004, 09:38 AM
S!


Looking at flight models of twin engine fighters, the Bf-109Z is very gentle on the stall and it's flight model is probably closer to what the P38's should be.


______

ZG77_Nagual
10-27-2004, 11:04 AM
QED Phillipscdrw http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif This one took.
Even the corsair seems to have a gentler stall.

p1ngu666
10-27-2004, 12:42 PM
koro, all evidenense points in my favour, ive not come across accounts of its stalls being like u described, and video evidence and the cloverleaf manouver indicate that it was stable under stall

there is a selection of aircraft u can fly in fb that stall WAY better. the j8a, go229,tb3,il2(any model)

koro, i havent flown a p38, have u ? http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

MEGILE
10-27-2004, 12:53 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by p1ngu666:

koro, i havent flown a p38, have u ? :wink2 <HR></BLOCKQUOTE>

http://gama.sloweb.net/1tao5a_awro-lui%20was%20owned.jpg

Korolov
10-27-2004, 01:18 PM
POINT A) The 109Z does NOT have a complete FM, and frankly, it stalls earlier than the P-38 for me.

POINT B) I'm not going to bother with Zeno's until they get a different video format. Realplayer sucks.

POINT C) Review these tracks - illustrating the P-38's stalls. "klv_p38stall100" is on 100% fuel, and the plane stalls out at about 70mph or 130kmh. Notice that by pulling on the elevator constantly, it will eventually induce a spin as I go below that stall speed. "klv_p38l25" represents 25% fuel, where the stall speed is even lower, coming around 120kmh or below 70mph. My guages probably read lower, but I wasn't zoomed in exclusively on the speedometer. Please note that I used maximum flaps in these tests, with 0% throttle, as the P-38 in the game *is* prone to torque (try it yourself... Drop flaps, kill throttle, get way down to 130kmh or about 75mph, then firewall throttle.)

http://www.mechmodels.com/fbstuff/p38stalls_1.zip

POINT D) Flying the P-38 goes both ways - you can neither say how the P-38 should fly, nor can I. However, as I can squeeze a lot of performance out of the P-38 as it's modeled, I have to assume other players can as well. The P-38 wasn't a easy plane to fly, and the game reflects that.

POINT E) J8A - biplane. Go-229 - Jet plane. TB3 - Quad engine, 1930's bomber. IL-2 (any series) - Single engine attack plane.

I don't see any Twin Engined, high performance interceptors amoung that list, do you?

ZG77_Nagual
10-27-2004, 01:47 PM
I agree the 38 has alot of potential in game. I personally prefer the J and use trim in leu of dive flaps. It's the very twitchy turn performance and abrupt wing drop that bothers me more than the straight stall-speed. I think it is a bit off in relative performance. Not huge - but significant. I think the 38 should fall off the turn more as described in descriptions of the cloverleaf maneuver - which was an actual combat maneuver employed by this A/C and which the in game 38 really not able to pull off with much success due to the wing drop.

Korolov
10-27-2004, 02:03 PM
I don't even think that's possible in the game, Nagual. A plane seems to always wing over at or below it's stall speed, no matter the type.

The only solution I can think of is to not push the plane to the point that it does snap out, and to be very fast on the rudder.

p1ngu666
10-27-2004, 04:16 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Korolov:
I don't even think that's possible in the game, Nagual. A plane seems to always wing over at or below it's stall speed, no matter the type.

The only solution I can think of is to not push the plane to the point that it does snap out, and to be very fast on the rudder. <HR></BLOCKQUOTE>

UNLESS its a j8a, il2, go229, he111, tb3
which is the point, the il2 game engine isnt incapable of doing soft stalls.

oddly the torque thing reminds me of me163, THAT can suffer from sudden power on torque http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif or it used too.

video at zeno's is a good watch, get realplayer alternative or something, basicaly, the plane rises up abit, then sinks abit lazyly.

its not a question of performance per se, or when the plane stalls, its HOW it stalls is the important part.

btw because of teh last p38 thread i did pretty well in the p38, sods/murphys law i do belive
http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Korolov
10-27-2004, 05:31 PM
Interesting that you bring this up again, Pingu - I just tried the P-38J @ 25% fuel. See track. I recorded it in .ntrk format in case you're running PF - this is in version 2.04.

http://www.mechmodels.com/fbstuff/p38nostall2.zip

VFA-195 Snacky
10-27-2004, 09:50 PM
Korolov, try a power on high aoa stall. The stall test you did in that track is incorrect and I can make any plane do that with power off and holding a proper aoa. The issue here is the stall characteristics with power on at high AOA until loss of lift occurs. There should be no torque to roll the P38 over but in FB there is. Carefull you dont confuse an accelerated stall with what we are talking about here. It's a shame you refuse to watch the training film, it explains a lot and since none of us have first hand experience that's as close as we can get.

WUAF_Badsight
10-27-2004, 10:18 PM
i tried to DL the RealPlayer movies at Zvenos & play them with what i have , as no way do i want realplayer

but no go . . . . is there anything that will work the files & play these movies ?

Korolov
10-27-2004, 11:53 PM
Define "high AOA", Snacky. Do you mean straight up 90 degrees, then hammerhead over? Or something to the tune of 45 degrees and mush over?

I tested both, and in neither case, was able to get a sharp wing snap a la the Fw-190. By being very gentle with the elevator, at 45 degrees I mushed over, nose forward at about 110kmh, with very light elevator pressure. In 90 degrees, I pulled up slightly at about 100kmh to flip the plane over, with neither wing flipping ahead of the other.

Could I ask you guys to provide a track of combat and non combat flying, to help describe to me what you're doing, and what you think is wrong?

VFA-195 Snacky
10-28-2004, 01:57 AM
Korolov, We are talking about torque here not whether the aircraft rolls over at full flaps with 0 throttle. I can make the P51 "glide" like you did in that track, that is not a proper stall test.

You can start at 45 degrees, but you need to apply power (above 70%) and wait for the aircraft to run out of speed and the wing to lose lift. The real P38 would nose over since there was no torque to "snap" it from one side to the other. In FB the aircraft will snap or roll over.
This is the problem.

I made a track showing the difference between your stall test and what the stall test used in the training film looked like, except in the training film the results were different where the real aircraft simply nosed over and accelerated, in the track I made (without adding backpressure before you claim that I did) the aircraft snaps violantly and into a flat spin. This is Torque induced.
Another problem is the need to trim rudder to level the aircraft. Why? you should not need to trim rudder to counter torque effect on the P38. You will say that you dont have to, but I assure you my stick is calibrated and there is 0 spiking, but yet I still must apply rudder trim to counter torque on the P38.
You said so yourself many times Korolov that the P38 in FB has torque issues so why all of a sudden you now tow the company line and say there is nothing wrong??
I don't want to argue about this, but there are a few problems with the P38 in FB that are pretty hard to overlook.
I only wish you could watch the training film as you would see exactly what I am talking about. http://forums.ubi.com/images/smilies/51.gif

btw- I have no way of hosting the track for download right now, but I could email it if you like. Otherwise you will have to wait until I find a host tomorrow.

p1ngu666
10-28-2004, 07:24 AM
u can get a program called real alternative, plays realplayer stuff wid wmp6
its what i use http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

the snap stall is perticaly prevalient in turns aswell

i dont have time for a proper reply, sorry :\

ZG77_Nagual
10-28-2004, 08:06 AM
It is true that other A/C handle the stall/turn better than the 38 - I cited the corsair as one example. The 38's first instinct to abrupt elevator at moderate speed is to flip over very quickly. The 38 does have torque in real life of course - it's a bit complicated and involves relative aoa of the props but the upshot is this ac should be one of the mildest in terms of the tendancy to flip during a turn - instead of one of the most temperamental. I'm speaking relative to other ac in the simm so obviously it's not an fm limitation. Cranked in a turn it should be more inclined to mush than flip. - that is from quite literally everything I've read on the subject. Opinions vary on it's efficacy as a fighter (depending, I think, on familiarity with the ac - and willingness to make it work) but not on this.

VFA-195 Snacky
10-28-2004, 11:05 AM
The Corsair had a nasty tendency to flip toward the left when entering a stall. A huge prop and massive amounts of horsepower caused the Corsair to be very dangerous at low speeds.

I don't think the IL2 engine was ever designed to have any counter rotating propellers. Twin engine flight models are one thing, but the P38 is the only aircraft in FB with counter rotating props and I think that screws up the numbers in FB. If it is a game engine limitation then we may never see the P38 correctly modelled, one can only hope for something new in BOB if that happens.

Korolov
10-28-2004, 02:35 PM
Snacky, I was applying power in both cases. I could get a wingover in neither case. At 45 degrees, if I was pulling real hard on the stick to maintain the same angle, the wing would snap over. If I was being very gentle on the stick, the plane just slowed down to about 110kmh and nosed over.

And hey buddy, no need to say I'm mowing you down - I'm simply asking you what you think is wrong. Bear with me, here - I've flown twitchy, crappy planes since day 1, so bad characteristics are a bit hard for me to see. So help me out here.

Now, I understand you want the plane to not wingover whatsoever, correct? What I'm arguing is that wingovers can and will occur in this plane, even with counter rotating props. Counter rotating engines don't equal godly flight performance. Additionally, I think we need to remember exactly what a stall is; the "stall" message in FB is misleading and I think it really means "snap" rather than "stall".

So essentially, you're looking at a plane that doesn't have the onset of a snap, but can if pushed too far. I doubt there's any way to change that since every plane in FB does it, but I honestly don't think the P-38 is that quick to wingover.

Lastly, I've said it before, my stick is very loose, and so I have a hard time telling between what torque is in flight on any plane, unless it's very slow with the addition of power as described above. That doesn't mean it's not there, just that I don't notice it.

I think you guys need to ask yourself this: Can a 15,000lb, combat loaded fighter, outturn a 7,000lb combat loaded fighter? The answer is, yes, but that requires the heavier fighter pilot to be much more experienced than the lighter one. Given equal experience, then there's no doubt in my mind, it falls to which pilot gets the initiative first.

XyZspineZyX
10-28-2004, 03:14 PM
There are two kinds of stalls that need to be considered I think.

In the standard level stall, both wings drop their lift at the same time and the plane mushes out or noses over. If the aircraft suffers a lot of torque due to a full power engine (say, Corsair or FW) then the plane might actually wingover when performing a level stall. My understanding is that not a few Corsairs flipped in the early days on carrier landings due to this rather wicked torque problem. However, as we all know, the P-38 has counter-rotating props and so should suffer little if any torque troubles in a standard level stall.

The other kind of stall is a turn-stall. In this case because the aircraft is in a bank and one wing is moving slower than the other, the slow wing gives out while the other still has sufficient lift to remain airworthy. This results in the aircraft flipping even if is not suffering from any significant engine torque. Even a P-38 should be susceptible to this rather fundamental principle of aerodynamics.

Whether or not a wingover in a turn stall is violent, I'm not sure all of what determines that. But since the P-38 has a tremendous amount of inertia in the roll axis (heavy engines spaced wide, huge wingspan), I would think that the P-38 would suffer a much more gentle wingover in a turn stall than aircraft that are very good rollers with light wings... like a FW say.

Does the flight model account for mass distribution in the airframe? Would the P-38's high rotational inertia automatically be a factor by virtue of the core physics engine?

VFA-195 Snacky
10-28-2004, 09:33 PM
Korolov if I came across wrong I apologize, that wasn't my intention. I think basically what we have is one group being "Happy with it" and the other group "wanting a change". The training video shows exactly what I am talking about and I really hope you are able to view it somehow in some way. When you say wingover I think of an accelerated stall which can occur with any aircraft. What I am trying to explain with the P38 is a mushy feeling (if feeling the plane was actually in the sim) followed by a buffet and then nose over as the wings lose lift. In FB I do not get a mush feeling followed by a nose over. I get a roll over or snap roll.
I can email the track I have if you like and maybe that will help explain. Send me a messege at ldowningjr@gmail.com and I will send it to you if you would like to see. I don't doubt your abilities whatsoever so let's make that clear right now, But I have also flown in real life and in sims for years so I am not basing my view of the P38 on blind opinion. I don't expect the P38 to fly like the 109Z, but I would like it to handle the way the real pilots say it did.
Perhaps it is a stick setting or the way you have your sliders setup. We could compare and see, but I try to fly these planes as I would a plane in the real world so you won't find me jerking the plane around and over stressing the airframe like many others do.

Anyway, I'm rambling, sorry. My point is I feel there is too much torque with the P38. The P38 should be more stable than it is currently.

Korolov
10-28-2004, 11:08 PM
The wingover you describe is generic to all planes in FB. I don't really think it's possible to change it, short of turning off stalls and spins in difficulty settings. Additionally, as I said before, I think that FB's stall message is misleading, and that you're actually stalling at a much earlier point than that.

Another thing that I think we should keep in mind (and this has been beaten to death) is that we can't trust real pilot's take on things. It makes a good basis, but in the long run you'll only get a small piece of the pie. For every good thing said about the P-38, there's always a equal and opposite bad thing. I would love to use so and so's interview to present a case, for example, of extreme maneuverability on the part of the P-38. But there are always dozens of other interviews that suggest that it wasn't such a great performer, as well as actual hard data. (AHT)

However, according to Sandman, who just got PF, he says that the P-38 gained a lot of improvements, so perhaps Nagual's impressions aren't necessarily correct.

Lastly, I would like to remind you, that McGuire died in a P-38 wingover/snapstall. While the argument that he did fall into it was due to his drop tanks, it nevertheless suggests that the plane could be thrown into such a state if pushed to that point.

VFA-195 Snacky
10-29-2004, 11:06 AM
Oh well then I guess we are back to where we started with this.lol You are not going to convince me and I am not going to convince you.lol
I personally dont notice a change with PF, but I will reserve the right to spend some more time with it before I say anything. http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

ZG77_Nagual
10-29-2004, 11:59 AM
What we do have is the 'cloverleaf maneuver' - which cannot be implemented successfully in the sim - but was used in the p38 in combat during low speed level dogfights to outturn 109s.
I wouldn't say I'm not happy with the p38 - just that it is a tad off.

Korolov
10-29-2004, 01:22 PM
I don't see the cloverleaf maneuver as some all-godly outturning maneuver that only the P-38 could perform. I can see it as a way to stall someone on your tail out, but outturn? Most 109 pilots will just haul on the speed and go up and come down on you - better to avoid getting slow in the first place.

DIRTY-MAC
10-29-2004, 06:52 PM
I suggest you send all your proofs to oleg
if you havenāĀ“t

Aaron_GT
10-30-2004, 04:47 AM
The P38 has two props and two sets of torque which tend to cancel out. However it isn't going to be immune to be totally immune flipping at stall as it is possible that the two wings may stall at slightly different points. At the point of stall of one wing before the other the secondary effects of the torque and so on of the engines on the wing that is just stalling and the other wing will be different. The effect should be milder than a twin with props that rotate the same way, which should in turn be milder than a single engined, single prop plane. However the mildest effect is likely to be from having counter rotating props on a single spinner. With the P38 there shouldn't be any preference for direction of departure, which isn't going to be the case with other twins.