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drose01
06-12-2005, 10:56 AM
I'm enjoying flying the new P38 alot, and the P38L late is a serious beast. I love the way it behaves on takeoff and landings.

My problem is locking up in dives. In a high speed combat situation when I try to follow my opponent down, too often I get in an unstoppable lawn dart maneuver. The plane just wont pull up.

What strategies, other than avoiding diving, do P38 specialists use to get around this?

MEGILE
06-12-2005, 11:01 AM
Trim on a slider, and airbrakes.

BUG3222
06-12-2005, 11:16 AM
Use ur rudder to break the speed.
I love flying the J and its very capable.

F19_Ob
06-12-2005, 11:22 AM
As Megile said , use airbrakes on L variant. U have to assign a key for it in settings.
Always throttle idle and apply combatflaps in dives since the p38 picks up speed fast and has trouble declerating.
If I notice I go too fast I either pull elevator or spiral while pulling hard. This way U still can keep the enemy in sight.

hope this helps http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

horseback
06-12-2005, 11:57 AM
The real P-38 was big and heavy, and picked up speed in a dive very quickly. Unfortunately, because the design, while streamlined, had a lot of bumps and bulges, the aircraft reached 'compressability' quite quickly. Much sooner, in fact, than its single-engine contemporaries.

Compressability, for the sake of simplicity, is that point where some of the air passing over you airframe exceeds the speed of sound, and the shock waves resulting from this carry back over your fuselage and lock up your aft control surfaces, most notably your elevator. Usually, an aircraft reaches compressability at a specific fraction of the speed of sound, continues in the dive at an ever increasing angle, and 'tucks under' ata extremely high speed, usually resulting in a catastrophic failure of the airframe.

This phenomenon was first identified at about the same time the P-38 and P-47 were designed, although it had been around for a while. The crashes it caused before these heavier constructed high performance aircraft were built were attributed to pilot error, oxygen deprivation or some structural failure most of the time. It took a while to figure out the real culprit, and find effective fixes for the problem.

At higher altitudes, where the air is thinner and the speed of sound is much lower, this translates into a very dangerous situation for a P-38, which could reach compressability at some extreme alts in level flight (a situation guaranteed to overwhelm the capacity of anyone's relief tube), and in even shallow dives above 20-25,000 ft.

Below these altitudes, the thicker air raised the Mach number too high for the Lightning to reach its compressability fraction, and it could zoom and boom with the best of them. Installation of the dive brake in late J and L models are supposed to have fixed the problem as it applied to combat situations almost entirely.

The aircraft in the game all have some modelling of compressability, and the Lightning's was particularly unforgiving, even at low altitude, prior to the latest (unofficial) patch, which led to much weeping, wailing, and gnashing of teeth. One can only hope that things have gotten better and may even approach the real thing.

I haven't had a chance to try out the Lightning in the 4.0 patch yet (still trying to master the takeoffs and landing in the 109 and Mustang-God help me when I get around to the I-16 and P-40!), but I hear that is much improved. Try real-life tactics: keep your dives relatively shallow, apply the dive brake early, and spiral down after your opponent.

cheers

horseback

drose01
06-12-2005, 12:22 PM
Thanks for the tips.

Regarding whether the 4.0 P38 still has this problem at low alts, I have to say it does seem to.

My most recent death dive occurred while pursuing a 109 from an alt of about 1200 meters or so, starting at a cruising speed of about 475 km/h.

BSS_CUDA
06-12-2005, 01:21 PM
KPH or MPH???? 475 KPH is below 300 MPH you should have zero problems at that speed, as far as the lawn dart syndrom, there are a couple of ways around it, in the pacific before the J25-LO they would dive in a spiral to keep the speed resonable, the fowler flaps will eliminate any dive issues on the L so I dont understand why your having problems, try keeping your angle more reasonable in a dive with the fowlers extended you should be able to stand her on her nose and not go over 400 MPH

AerialTarget
06-12-2005, 01:42 PM
Fowler flaps are different from the dive brake.

The P-38 Lightning in the game (three point zero four) reaches compressability too early, it is true. Also, it is possible to get out of it in the J by throttling back. But in the L (the nerfed one), it is not possible to get out without either deploying combat flaps or the dive break. Of course, deploying flaps at that speed would damage them in real life, but then in real life compressability happens later and can be gotten out of my chopping power.

AFSG_Bulldog
06-12-2005, 04:04 PM
Originally posted by AerialTarget:
The P-38 Lightning in the game (three point zero four) reaches compressability too early, it is true.

Can you post your aerodynamic compressibility calculations to show that the P-38 reaches compressibility too soon? And how late should it occur?

According to The Smithsonian National Space and Air MuseumN.A.S.M.) (http://www.nasm.si.edu/research/aero/aircraft/lockheed_p38.htm)


The most vexing difficulty was the loss of control in a dive caused by aerodynamic compressibility. During late spring 1941, Air Corps Major Signa A. Gilke encountered serious trouble while diving his Lightning at high-speed from an altitude of 9,120 m (30,000 ft). When he reached an indicated airspeed of about 515 kph (320 mph), the airplane's tail began to shake violently and the nose dropped until the dive was almost vertical. Signa recovered and landed safely and the tail buffet problem was soon resolved after Lockheed installed new fillets to improve airflow where the cockpit gondola joined the wing center section. Seventeen months passed before engineers began to determine what caused the Lightning's nose to drop. They tested a scale model P-38 in the Ames Laboratory wind tunnel operated by the NACA (National Advisory Committee for Aeronautics) and found that shock waves formed when airflow over the wing reached transonic speeds and became turbulent. Lockheed never remedied this problem but the firm did install dive recovery flaps under each wing in 1944 to restore lift and smooth the airflow enough to maintain control when diving at high-speed.

I think Oleg and his crew have done a great job with this sim. It is better than anything else out there. What other game developer actually listens to all of the 14 year old armchair aerodynamists and actually tries to make everyone happy? I'll tell you NONE.

Call up Micro$oft and try the same thing and see what you get in return. Heck M$'s Tucker even remarked in an online chat that there was nothing wrong with CFS3.

I think Oleg and his team should just develop this sim like they believe the sim should be and quit listening to all of the whiners.

If you don't like the canopy glare or think the 50 cals are too weak or too strong or the muzzle blasts are too big...whatever...go somewhere else and complain. Try Micro$oft.

Me ... I am going to enjoy the fun (warts and all) this sim offers and enjoy all of the support the developer offers for FREE.

VF-29_Sandman
06-12-2005, 05:58 PM
u'll wind it up to 400+ in a dive very quickly. u could deploy the dive break just before entering the dive. just remember to raise the brake on pullout or u'll lose all the speed u've built up just as fast.

Grey_Mouser67
06-12-2005, 06:44 PM
I've been flying the lighting alot...and if you deploy combat flaps or airbrake in a dive and adjust your trim properly you can enjoy a little B&Z action for the first time since the introduction of the Lightning. I've also given away my advantage on a couple of occassions too because I didn't manage my dive speed...it is still important to come in at over 700km/hr...closer to 800 if I can get it. Trim is the key.

I'm still working on it cause its hard to find the sweet spot while in combat but I have done it on occassion with terrific results. Verrrry Coool to be fighting on relatively even terms in a Lightning. By the way...the zoom climb in the L late version is something to behold and I'm conjecturing but the accelaration of that aircraft may now be best.

I know I'm not faster than a D-9, but I've closed the gap on numerous occassions and the only think I figure is its superior accelaration as I haven't done any testing.

bolillo_loco
06-12-2005, 08:52 PM
Originally posted by AFSG_Bulldog:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by AerialTarget:
The P-38 Lightning in the game (three point zero four) reaches compressability too early, it is true.

Can you post your aerodynamic compressibility calculations to show that the P-38 reaches compressibility too soon? And how late should it occur?

According to The Smithsonian National Space and Air MuseumN.A.S.M.) (http://www.nasm.si.edu/research/aero/aircraft/lockheed_p38.htm)


The most vexing difficulty was the loss of control in a dive caused by aerodynamic compressibility. During late spring 1941, Air Corps Major Signa A. Gilke encountered serious trouble while diving his Lightning at high-speed from an altitude of 9,120 m (30,000 ft). When he reached an indicated airspeed of about 515 kph (320 mph), the airplane's tail began to shake violently and the nose dropped until the dive was almost vertical. Signa recovered and landed safely and the tail buffet problem was soon resolved after Lockheed installed new fillets to improve airflow where the cockpit gondola joined the wing center section. Seventeen months passed before engineers began to determine what caused the Lightning's nose to drop. They tested a scale model P-38 in the Ames Laboratory wind tunnel operated by the NACA (National Advisory Committee for Aeronautics) and found that shock waves formed when airflow over the wing reached transonic speeds and became turbulent. Lockheed never remedied this problem but the firm did install dive recovery flaps under each wing in 1944 to restore lift and smooth the airflow enough to maintain control when diving at high-speed.

I think Oleg and his crew have done a great job with this sim. It is better than anything else out there. What other game developer actually listens to all of the 14 year old armchair aerodynamists and actually tries to make everyone happy? I'll tell you NONE.

Call up Micro$oft and try the same thing and see what you get in return. Heck M$'s Tucker even remarked in an online chat that there was nothing wrong with CFS3.

I think Oleg and his team should just develop this sim like they believe the sim should be and quit listening to all of the whiners.

If you don't like the canopy glare or think the 50 cals are too weak or too strong or the muzzle blasts are too big...whatever...go somewhere else and complain. Try Micro$oft.

Me ... I am going to enjoy the fun (warts and all) this sim offers and enjoy all of the support the developer offers for FREE. </div></BLOCKQUOTE>

you do realize that at that altitude 320 mph (which is indicated) corresponds to 460 - 480 mph TAS.

America's hundred thousand by F. Dean page 158:

Dive and recovery
Due to its weight and streamlined design the P-38 accelerated rapidly in a dive. At a Mach number of .065 that is 65 percent the speed of sound in air, airplane drag started to increase sharply with the onset of compressibility. This Mach number corresponded to 440 mph true air speed (290 mph IAS) at 30,000 feet, or 460 mph TAS (360 mph IAS) at 20,000 feet. In one g diving flight (no pullup attempted) shocks stared forming at Mach .067 and aircraft buffeting commenced at mach .0675. At flight above one g, as in a dive pullout or a turn, buffeting developed at lower mach number. At 30,000 feet a pullout maneuver over three g got the P-38 in trouble. At lower altitudes the safe limits of speed and g level with out compressibility buffet occurrance expanded, since there were higher temperatures where for a given speed mach number decreased. The speed of sound was greater lower down, In any case compressibility effects really took over. At Mach .074 a nose down pitching tendency, or "tuck-under", started to steepend the dive.

I can find references like this in many books, this is for any P-38 model that does not have dive recovery flaps deployed.

now then on to olegs P-38 w/o the use of dive recovery flaps;

Up high sure its way over modeled, but so is every other a/c in the game.......seems that there is no way to correct this.

lets talk about altitudes below 20,000 feet where 38s didnt seem to have problems like they did above this altitude, and lets talk specifically about sea level.

using a generic atmosphere like have in the game the speed of sound at sea level is about 760 mph

.675 is when the aircraft begins to buffet, at sea level this is 513 mph tas/820 kph
.74 tuck under becomes critical ie loss of control, at sea level this is 562 mph tas/900 kph

our in game P-38 becomes uncontrollable at mach .55 - mach .56 over 100 mph 160 kph sooner than it should at sea level.

I believe that this is what the author of the thread is talking about.

here is a little more about the 38 diving at altitudes below 20,000 feet,

Attack & Conquer The 8th fighter group in WWII by john c. stanaway and lawrence j hickey isbn 0887408087

page 182: Five minutes later homer attacked another tony that went into a wild forty five degree dive. The P-38 was indicating 480 mph before it caught up to the tony at 6,000 ft.

same book page 214: West's 38 was registering 500 mph when he caught up to the Tojo and fired a deflection shot at an altitude of just a few hundred feet.

possum, clover, and hades 475th fighter group in ww II john stanaway isbn 0887405185

page 88: authur peregoy had led his flight with bartlett as his wingman on a bounce through a formation of zeros at 18,000 ft. The P-38 continued the dive at an indicated airspeed of 450 mph to lose the pursuing zeros easily.

protect avenge the 49th fighter group in WWII by sw ferguson and william k pascalis

page 126: tail end **** bong had come well within range of the intervening zeros and twisted his #80 into a vertical decent in excess of 475 mph. he pulled out just above the waves of the solomon sea and sped off ahead of his pursuers for serveral minutes to get some maneuvering room.

The 370th fighter group in WWII jay jones

page 285, P-38 mission: The germans were on one side of the rhine river and we were on the other side. There were some gun positions in houses on the german side that they wanted us to strike. We went in at 10,000 feet. The squadron commander said, "tally ho!" and went down. As he went down, the whole **** countryside lit up like it was the 4th of July. I wathed the other 11 guys go down after him. As I sat there I got worse and worse. I said, "This is horrendous. I'll never cut it." Anyway, I finally rolled in after the number 12 man. I turned my guns on and started giving bursts all the way down. I advanced the throttle to the stop. I thought sure as the devil I was going to get clobbered on this thing. I did a few gymnastics going down. By golly, I pulled out right on the deck and looked down at the airspeed indicator. She was doing 550. I never got a scratch.

AerialTarget
06-12-2005, 11:05 PM
Originally posted by AFSG_Bulldog:
Can you post your aerodynamic compressibility calculations to show that the P-38 reaches compressibility too soon? And how late should it occur?

Here you go, right out of the P-38 pilot's handbook!

http://users.adelphia.net/~j.r.engdahl/josh/divelimits.gif

You didn't think I could deliver, did you? This, combined with Bolillo Loco's informative post, should convince even the hard-headed that I do know what I am talking about when I say that the P-38 Lightning in the game reaches compressability too early. I do research these things before I make strong statements about them, unlike ninty five percent of this community. Therefore, kindly cease your insinuations that I am a fourteen year old armchair pilot.

bolillo_loco
06-12-2005, 11:26 PM
if the chart went all the way to sea level it would touch 500 mph. keep in mind that the dive chart is for mach .675 and that is when "buffet began" not loss of control, its out of the pilots manual.

BUG3222
06-13-2005, 03:58 AM
The p38 always be stalked by downtalkers

olegs isn't the only game to modell the p38 correctly btw. check aces high for example.
i can enjoy both games as much.

it is hard to believe but the p38 was a capable fighter and 1st choice in the pto until VE day.

The L model did serve well in europe also.

wonder why the 2 top aces flew the p38

OldMan____
06-13-2005, 07:47 AM
Originally posted by AerialTarget:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by AFSG_Bulldog:
Can you post your aerodynamic compressibility calculations to show that the P-38 reaches compressibility too soon? And how late should it occur?

Here you go, right out of the P-38 pilot's handbook!

http://users.adelphia.net/~j.r.engdahl/josh/divelimits.gif

You didn't think I could deliver, did you? This, combined with Bolillo Loco's informative post, should convince even the hard-headed that I do know what I am talking about when I say that the P-38 Lightning in the game reaches compressability too early. I do research these things before I make strong statements about them, unlike ninty five percent of this community. Therefore, kindly cease your insinuations that I am a fourteen year old armchair pilot. </div></BLOCKQUOTE>

yeap.. but in otehr hand.. out flaps and brakes in game can be deployed at ANY speed. Even this your chart says that Recovery flaps had its limits. (probably such large prousion under wing, disturbing air flow would generate very high forces, that probably were not very good for plane on long term.

horseback
06-13-2005, 09:29 AM
If I read the chart right, dive flaps can be extended at up to 470mph indicated at 5,000 ft (approx 1600m). I can't recall going much faster than that in the P-38 at low altitudes, unless I was already in the incorrectly modelled lawn dart mode.

At those altitudes, the real Lightning was supposed to have terrific elevator authority at all speeds nearly up to compressibility; AFAIK (3.04), this has not been reflected in the Il-2 series.

cheers

horseback

F4UDash4
06-13-2005, 12:48 PM
Originally posted by horseback:
The real P-38 was big and heavy, and picked up speed in a dive very quickly. Unfortunately, because the design, while streamlined, had a lot of bumps and bulges, the aircraft reached 'compressability' quite quickly.

"Bumps and bulges" were not the cause of the P-38's tendency to reach compressibility at a relatively low Mach. What did cause this was the thick wing, which was necessitated by the large fuel quantity required to meet the range requirement as spelled out in the original Army Air Corp contract leading to the Lockheed €œmodel 22€ design. This fuel had to be contained internally because of another inexplicable Army Air Corp declaration that no pursuit aircraft could be equipped with drop tanks.

bolillo_loco
06-13-2005, 12:57 PM
Originally posted by OldMan____:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by AerialTarget:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by AFSG_Bulldog:
Can you post your aerodynamic compressibility calculations to show that the P-38 reaches compressibility too soon? And how late should it occur?

Here you go, right out of the P-38 pilot's handbook!

http://users.adelphia.net/~j.r.engdahl/josh/divelimits.gif

You didn't think I could deliver, did you? This, combined with Bolillo Loco's informative post, should convince even the hard-headed that I do know what I am talking about when I say that the P-38 Lightning in the game reaches compressability too early. I do research these things before I make strong statements about them, unlike ninty five percent of this community. Therefore, kindly cease your insinuations that I am a fourteen year old armchair pilot. </div></BLOCKQUOTE>

yeap.. but in otehr hand.. out flaps and brakes in game can be deployed at ANY speed. Even this your chart says that Recovery flaps had its limits. (probably such large prousion under wing, disturbing air flow would generate very high forces, that probably were not very good for plane on long term. </div></BLOCKQUOTE>

yes and on the other hand every a/c in this game can deploy its maneuver flaps at any speed as well. Rather strange when you consider that historically most WWII fighter aircraft did not have a "combat flap" or a "maneuver" flap.

deploying the "dive recoery flap" causes the main wing to have more lift and causes enough drag to keep the 38 from gaining excessive speed in a dive nothing more nothing less. I have never read anything which said it had detrimental affects on the P-38 at any speed. The reason why the 38 began to "tuck under" at mach .74 is because airflow over the main wing had become disturbed and was no longer flowing over the wing. before it even got to the leading edge shock waves caused it to...for lack of a better word "bounce" away from the wing so that it only partially flowed over the first 1/3rd of the main wing. This caused the main wing to lose its lift. since the elevator was not affected by this it still had its lift and this caused the P-38 to "tuck under". The dive recovery flap restored lift to the wing and from what I have read created more lift at any speed. The only ill effects I could imagine it would have on the 38 would be during a single engined landing with gear and flaps down, deploying the dive flap would most likely be dangerous because in the above mentioned condition the 38 could no longer maintain altitude and began to sink, so the dive flap would make flight worse. I have never seen any speed limitations of the dive recovery flap it could be deployed at any time during the dive. I can post instances of Pilots using the maneuver flap at speeds of 300-350 mph IAS if you like, the placarded limit of the maneuver flap is 250 mph IAS in the cockpit and pilots manual.

BTW the P-38 met the usaac standards for G forces and was stressed for a normal work load of 8 postive and 4 negative Gs with a ultimate break of 1.5 times that figure.

AerialTarget
06-13-2005, 01:01 PM
Originally posted by OldMan____:
Even this your chart says that Recovery flaps had its limits. (probably such large prousion under wing, disturbing air flow would generate very high forces, that probably were not very good for plane on long term.

No, the limit on the chart (the speed shown plus twenty miles per hour) is the limit at which it is safe to dive. The manual sets no limits to the speed at which you can deploy the dive recovery flaps. The chart is indicating how fast you can safely dive without extending them. While using them, you can add twenty miles per hour onto your safe dive speed.

Maneuver flaps are another story. They have a two hundred and fifty miles per hour indicated limit.

By the way, the oft-quoted forty-five degree angle quoted by the P-38 haters is actually, according to the pilot's handbook, the maximum angle for a safe, sustained dive. It is not the maximum angle that a P-38 can dive at and still recover.

AerialTarget
06-13-2005, 01:04 PM
Originally posted by bolillo_loco:
the P-38 met the usaac standards for G forces and was stressed for a normal work load of 8 postive and 4 negative Gs with a ultimate break of 1.5 times that figure.

All right! I didn't know that; I've not yet memorized the pilot handbook. Ha ha! A human will break under gees before the P-38!

F4UDash4
06-13-2005, 01:12 PM
Another note on P-38 dive speeds, compressability etc.

According to Warren M. Bodie, author of the definitive P-38 Lightning book, the P-38 had NO compressibility problems if entering a dive from less than 25,000 feet altitude regardless of the speed of entry or the angle of the dive.

Try that in PF.

bolillo_loco
06-13-2005, 01:14 PM
even with dive recovery flaps the pilot's manual states that a 45 degree dive is safe from high altitude with the recovery flaps deployed.

book "Pilot" by tony levier with john guenter. page 128, in brief: milo and levier made sustained dive tests from 35,000 ft down to the deck. once levier reached a sustained 60 degree dive he began to suffer compressability with the dive flaps deployed. he states the the plane was flyable and he was in control during the entire dive, that all that was needed to counter the "tuck under" was back pressure on the stick. for obvious reasons they didnt test sustained dives with engines turning at 2,600 rpm any further they had reached the sustained high altitude dive limit of the 38.

pilots manual 45 degrees
levier and milo 60 degrees

I would believe levier over any manual any day. manuals are always very conservative to keep inexperienced pilots from pressing their luck.

now back to the main point of this topic. at 10,000 feet and lower the 38 suffers from compressability far too early.

horseback
06-13-2005, 01:19 PM
Gee, as I pointed out, I was simplifying it -but I would consider that gondola between the engines to be a fair-sized 'bump.'

The fact is that the P-38's wingshape/profile was not exactly a groundbreaking design, and while quite acceptable for aircraft up to that time, it was used on an aircraft that was intended to fly at speeds and altitudes that had been barely touched by the late thirties when it was designed. The thickness of the wing was not due to just fuel requirements-there was some cooling piping in the leading edges (oil cooler? Turbo intercooling? I'm at work now, away from my refs) as well.

AFAIK, the governments/companies/engineering staffs working on aircraft that had reached those altitudes and speeds were not exactly forthcoming about what they had found in their flights, and Kelly Johnson and his design and research team had to base their design on what they knew at the time...which did not include compressability.

Now, about the drop tank issue, I suppose we could point out that the P-38 was built to a requirement for a high altitude interceptor for the protection of the US coasts from potential cross-Atlantic bombing raids (where else would enemy bombers come from? Mexico?). The politicians who put those limitations on the US military were deeply concerned with the potential of constituants' complaints about Air Corps aircraft dropping things on their heads or property.

The very idea of being sucked into another European squabble (with the potential of Allies attempting to interfere with our self-governance - a real fear, if not a realistic one) was anathema to the majority of Americans at the time. It was thought that if we gave the military the weapons to fight a modern war, that they might find a way to get into one. Doesn't that sound familiar...

cheers

horseback

JG53Frankyboy
06-13-2005, 01:21 PM
perhaps the gameengine , rather old , isnt able to calculate this - compressability in comparison to altitude.........
just a guess

F4UDash4
06-13-2005, 01:29 PM
Originally posted by bolillo_loco:
now back to the main point of this topic. at 10,000 feet and lower the 38 suffers from compressability far too early.

Correct!

Below 25,000 feet the P-38 should NEVER enter compressibility.

AerialTarget
06-13-2005, 01:38 PM
In addition, the pilot should have full elevator authority before compression, unlike how it is in the game with much trim being absolutely required for full elevator authority at speeds greater than three hundred and eighty or so. Apparently the game models one hand on the stick only; that explains why we can't pull up at four hundred miles per hour indicated. A real pilot wouldn't stupidly keep his hand on the throttle when he was crashing in because he couldn't pull back the stick hard enough!

F4UDash4
06-13-2005, 01:41 PM
Originally posted by horseback:
Gee, as I pointed out, I was simplifying it -but I would consider that gondola between the engines to be a fair-sized 'bump.'

But the gondola, whether or not you consider it a €œbump€, did not contribute to compressibility.


Originally posted by horseback:
The thickness of the wing was not due to just fuel requirements-there was some cooling piping in the leading edges (oil cooler? Turbo intercooling? I'm at work now, away from my refs) as well.

The leading edge turbo intercooler contributed nothing to making the wing thicker, the thickness of the wing was attained about one third back from the leading edge not at the leading edge.


Originally posted by horseback:
AFAIK, the governments/companies/engineering staffs working on aircraft that had reached those altitudes and speeds were not exactly forthcoming about what they had found in their flights, and Kelly Johnson and his design and research team had to base their design on what they knew at the time...which did not include compressability.

Johnson knew quite a bit about compressibility, as he predicted even before the first flight of the XP-38 that the craft would encounter compressibility.


Originally posted by horseback:
The politicians who put those limitations on the US military were deeply concerned with the potential of constituants' complaints about Air Corps aircraft dropping things on their heads or property.

All historical material indicates that the decision was a military one, not political. Whatever the reason it was foolish. Lockheed thought so, Lt. Kelsey thought so, and they went ahead with designing the provisions for drop tanks anyway. And luckily when Gen Arnold asked how soon the P-38s could be fitted with drop tanks the answer was €œwithin weeks€. It was obvious to Gen Arnold at the time that the Air Corp order had been ignored.