Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: F4UDOA on February 20, 2006, 03:44:57 PM
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When did the fowler flaps become part of the production airplane?
Did the P-38F have them?
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AFAIK the fowler flaps were there right from the beginning. Combat flap setting was introduced during the production of F model.
gripen
edit: grupen transforms to gripen
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The P-38 always had the flaps but! P-38G models had strengthened Fowler flaps which could be used at combat speeds up to 250 m.p.h. to tighten the turning radius. In Europe, pilots of the big Lightnings now found that they could turn inside of the smaller German fighters, particularly at low altitudes. They also had more powerful engines (a 100 hp increase). Production began in August 1942. The "H" model was similar.
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Originally posted by F4UDOA
When did the fowler flaps become part of the production airplane?
Did the P-38F have them?
The Fowler flaps were present as far back as the XP-38. They were always on the P-38. Somewhere around the late E early F model (I'd have to go look real deep in Bodie's book) a combat setting was introduced to enable a notch of flaps to be deployed at a relatively high speed. There were problems on the XP-38 with the flaps. The linkage was not strong enough, and some "stop gap" measures were taken to fix the problem.
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Originally posted by Captain Virgil Hilts
The Fowler flaps were present as far back as the XP-38. They were always on the P-38. Somewhere around the late E early F model (I'd have to go look real deep in Bodie's book) a combat setting was introduced to enable a notch of flaps to be deployed at a relatively high speed. There were problems on the XP-38 with the flaps. The linkage was not strong enough, and some "stop gap" measures were taken to fix the problem.
The maneuver flap setting was introduced with the P-38F-15-LO.
My regards,
Widewing
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Thanks. I've been a little busy, and lacked the time to look it up.
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the p-38 didn't originally have "dive flaps" until i think the L model or the J now kits for the field were made but the plane carrying them was shot down by a RAF plane and all 100 kits were lost with the plane carrying them.and the were made to combat compressibilty wich if put into a high alttitide high speed dive the plane would go into the compresibility range wich was the lift decreasing as the plane whent in the area close before supersonic flight and the air turbulance would beat the plane into peices and break the tail and the the rest of the plane would just desintagrate.the sound of a p-38 in the compresibility range made a horrible banshe wail as the chargers sucked air in and the we would hear a soft thump and then we knew what had happened then you would see what was once a p-38 fall from the sky.we lost many good friends like that.but sometimes the plane didin't desintagrate but instead did an outside loop.i had one such experience but i still loved and still do love that p-38 but after that flight i had to get a new flight suit.;)
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BTW, the flaps used on Late-Model Js and all Ls were not "Dive Flaps". They did nothing to slow the aircraft, they simply changed the lift profile of the wing to reshape the airflow and prevent shockwave buildup.
And they had to be deployed before the aircraft was in its dive, as deploying them at any high speed (above about 400mph) would cause a sudden pitching up of the nose and a loss of control similar to a high-speed stall.
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that's what i was trying to say.sortof.the reson i called them "dive flaps" is becuse i was not sure what they where actually called.
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"dive recoverly flaps" if you want to be technical about it.
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thanks
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The first P-38 to be shipped from the factory with dive flaps installed was the P-38J-25-Lo (the P-38J in AHII is probably a P-38J-10-Lo, and does not have them).
They WERE dive flaps, what they were not is dive brakes, as you see on dive bombers.
The dive flaps on a P-38 did not need to slow the plane down. The drag violently increased when the shock wave formed around the center wing at Mach .65.
The dive flaps were SUPPOSED to be deployed BEFORE you entered a dive, but they were often deployed AFTER the dive was started.
The first improvement for the P-38 to solve the dive problems was actually the fillet radius change where the center wing joins the center nacelle.
Something else that had a great effect was the fit around the windows. That area has to be properly fitted and adjusted, or the gaps and distortion will cause severe airflow disruption. That is the reason for the red "No Step" sign under the windows. As little as a 1/16" gap could cause severe problems.
According to several pilots, you could use the dive flaps (they called them "speed boards") in combat to get a momentary "pitch up" of as much as 15 degrees, which you could use to get a quick shot off at times.
The external counterbalance weights on the elevator did absolutely nothing for compressibility. The elevator already had the weight built into it from the beginning, it had a thicker sking and more bracing.
The NACA airfoil profile of the P-38 wing was the cause of the compressibility problems. It accelerated the air faster and earlier than other profiles. It was a tradeoff. That profile allowed a great deal of fuel to be stored in the wing. It also had a very high aspect ratio, which is what makes the P-38 climb and turn well. It helps make up for the relatively high wingload of the P-38.
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true
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A silly off-topic question that isn't worth it's own thread:
Did P38s serve in the RAF or RCAF?
Bozon
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Almost Bozon , I believe Brits took over French P38 order but well it was not really P38 "Lightning" but more P38 "TeaPot Storm" having their turbocompresseur removed but the 38 specialist here can certainly answer more precisely than I can.
Perhaps did the Brit use the recon version (F5 ...) all I know is St Exupéry lost his life in a F5B of the Groupe de Reconnaissance II/33
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'Turbocompresseur' How delightfully French :aok
The details of the British P-38's elude me, but I guess it is 'Googleable' in seconds. Or I wait until Widewing fills in the details :D The Brits also took over P-39's and P-40's didn't they? I've seen pics of P-39's in RAF markings.
Straffo, I wonder why the RAF would use P-38/F-5's when they had Spits and Mossies for that role. Do you know?
Edit, I indeed found the story in seconds:
http://home.att.net/~jbaugher1/p38_7.html
Note in particular the comment of the 'castrated' P-38... no turbochargers and two right handed engines!
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Bozon,
The Brits tested the P-38F and liked a quite a bit for a large aircraft. I do not know if they ever took it into combat.
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RAF rejected the 38s they were offered. The French operated recce 38s. The RAAF operated some hand me over recce Lightnings they got from 5th AF.
I don't think anyone else operated fighter variants outside of the USAAF during WW2.
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Brits took off the superchargers, made Lockheed change it so both engines rotated in the same direction, and changed the armament to Brit-standard guns.
Needless to say, its perfomance sucked and it was rejected. USAAF took over the order, removed the guns, restored the 'handed' propellors (but left off the 'chargers), then used them as test airctaft or inflicted them on advanced students as type-trainers. They were known as 'castrated lightnings'.
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thanks
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Hi Treize,
>Needless to say, its perfomance sucked and it was rejected.
Hm, relying on Baugher's article, I can't blame the British for ordering the turbocharger-less Lightning I in early 1940 when they were guaranteed a top speed of 400 mph @ 16900 ft. That was way ahead of any service aircraft of the time, and it was better than what the Spitfire V running at +16 lbs/sqin offered two and a half years later.
(The use of an un-turbocharged Allision not only reduced weight, but also increased total engine output by the exhaust thrust, so both climb and top speed improved by the omission of the turbo-supercharger. Below full throttle height, that is - and in early 1940, there was probably not much reason to expect the combat altitude to increase the way they eventually did.)
The decision for equal-handed engines is understandable as well as the vast majority of all twin-engined aircraft of that period handled quite well with both engines turning in the same direction. I'm not even sure that the bad reputation of the Lightning I's handling qualities is fully deserved - of course handed engines greatly reduce the pilot workload and probably helped to ameliorate some quirks of the basic airframe, but I didn't get the impression that we're talking about prohibitively evil characteristics, like for example the Me 210 demonstrated.
The very quick rejection of the Lightning I is a bit surprising, and it would be interesting to learn more about it. Could it have been a simple failure to match guaranteed performance? The 400 mph figure does not sound all that bad considering the difficult situation of the RAF in 1942!
Regards,
Henning (HoHun)
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Bozon,
Give me your email and I will send you the 9 page AFDU of the P-38F (American version) where it is tested against the Spit IX and partially against the FW190.
I also have a P-47 (B or C) AFDU where it is tested against the P-38F.
I will send them both.
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Lockheed had enough troubles keeping the orders filled for the USAAF in the PAC, MED and ETO in 1942, even if the Lightning I was ordered, I find it unlikely the RAF would have received them in the timeframe they wanted. That might also have had a part to play. In the end the only US fighter a/c the RAF used in the ETO in any quantity was the P-51B/D (Mustang III/IV) and the Mustang Is in the Recce role, with the P-40s going to the MED and to the RAAF in the PAC.
The P-39 was also rejected by the RAF after a short trial basis with one Sqn (UK based).
The P-47 was adopted for use with the RAF, and served in the CBI.
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Originally posted by hogenbor
Straffo, I wonder why the RAF would use P-38/F-5's when they had Spits and Mossies for that role. Do you know?
They didn't wanted to take pictures from orbit ?
:)
Seriously ,it was just an hypothesis
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Originally posted by Guppy35
RAF rejected the 38s they were offered. The French operated recce 38s. The RAAF operated some hand me over recce Lightnings they got from 5th AF.
I don't think anyone else operated fighter variants outside of the USAAF during WW2.
the italians operated one to fairly good effect
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The Lightning didn't really meet the promised performance criteria. Besides, the British soon realized that low altitude performance wasn't what they needed.
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Originally posted by storch
the italians operated one to fairly good effect
Only if you are a fan of Martin Caiden's writing :)
One must have the Caiden vs the truth O'meter running at all times.
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Originally posted by F4UDOA
Bozon,
Give me your email and I will send you the 9 page AFDU of the P-38F (American version) where it is tested against the Spit IX and partially against the FW190.
I also have a P-47 (B or C) AFDU where it is tested against the P-38F.
I will send them both.
COOL, I'd love to read it.
My email is now updated in my user profile.
Bozon
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Infact the A&AEE report on Lightning I is quite positive but IIRC the speeds were limited to something like 350mph due to reports from the states about the compressibility problems. Only two Lightning Is reached UK (no service use).
The Lightning II had turbochargers and handed engines (basicly similar as the P-38F). The BAC report on Lightning II can be found from here (http://marinergraphics.com:16080/ww2/alliedair.htm). None of the Lightning IIs reached UK (only testing in USA).
gripen