ALternatives for the P-38?

davebender said:

Germany wasn't invited to the competition so the U.S. Army Air Corps won't be building a Fw-187 clone. I don't think Britain was invited either.

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Nonetheless foreign designs could influence and inform other aircraft developments.Even in wartime aircraft development doesn't happen in a vacuum. How many designs were influenced by the Fw 190?
Maybe the Fw 187,an aircraft barely known outside the German aviation industry (including most of the Luftwaffe),was not so influential.I would suggest that the de Havilland Mosquito influenced the design of the Ta 154. The Ta 154 was a pretty miserable effort but that's Tank's fault.

It speaks highly of the P-38 that noone can really suggest any serious alternatives with anything approaching the required performance. I've always had a fairly neutral view of the P-38 but it may be an under rated type,at least in the ETO.

Cheers

Steve

Shortround6 said:

The problem with low risk is that it is low performance. We know what happened to the Lockheed 322.

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The 322's main failure was engine choice: it was flying in 1942 with engines of 1940, the C-15s. Plus, those were same non-handed (ie. of same rotation), and that was a non-no for the P-38. The late 1941 gives the opportunity to install the F-3, and by mid/late 1942 the 8.8:1 engines can develop 1500-1600 HP at WER, at 4500 and 2500 ft respectably. The late 1942 gives opportunity to mount the 9,6:1 engine (F-20) giving 1125 HP at 15500 ft, and WER of 1410 HP at 9500 ft . All values without ram effect. So basically the plane has the power to weight ratio better than Mosquito, and less drag. Of course, the engines need to be handed, so it's not just simply bolting the engines from the P-40 (as I've initially proposed).

Unless you are proposing cutting back the number of rounds carried per gun substantially I think you are going to wind up with an airplane, even with turbos, that under performs the P-38. you want at least one extra extra cannon. More fuel than was carried until the J model, a larger fuselage (balanced by the lack of twin booms?). Thinner wing may help with compressability but a thinner wing (if built of the same thickness materials) isn't as strong so it needs more structural weight. P-38 already had Fowler flaps.

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Some 400 rounds per HMG.
The fuel tankage of 350-400 gals should not hamper the performance too much, at least not the speed. More so since we have thinner wing and turbines giving exhaust thrust. The RoC will be hampered, I agree. But, by how much? The extra 100 gals mean some 700-800 lbs more (with fuel tanks accounted for). Sot the plane jumps from 16300 lbs ( historical -F/-G) to 17000-17100 lbs, or 4%.

I think it is very possible for something like the Curtiss A-18 Shrike to have been made into a single seater, with revised wing airfoil (and popssibly overall size) and improved aerodynamics. If the Allisons of the P-38 were used, it would surely perform acceptably, if not quite as well as the P-38. The lines are similar to the Fw 187, which itself could never have been adapted for Allisons or Merlins. The Jumo 210 was a 600 – 700 HP engine of about 980 pounds dry weight. The Allison and Merlin were both bigger and about 50% heavier. Using either would mean heavier loads on the wing, bigger propellers that would need longer landing gear, and a host of other issues.

The Grumman F5F could have been developed EASILY. It has potential, but was not pursued, but could have been.

I don't think the USA would have purchased a British design, or any other nation's design before 1942. If they did at that time, deployment would not be until sometime in 1943 I imagine. If so, the Fokker G.IA seems like a good candidate with some redesign. It is another twin-boom unit. The Gloster Repaer (F 9/37) is another candidate for consideration and has potential, though it still needed development. Another one I like is the proposed Soviet Grokhovsky G-38, another twin-boom design.

The IMAM Ro.58 was also a good contender, but was itself not flown until 1942, so it likely wouldn't make the cut for consideration.

We already know that conventional twin layouts work. Consider the Japanese line of rather conventional twins including the Ki-45, Ki-46 III and IV, Ki-96, Ki-102, Ki-108, etc. The plane I proposed in at the top of this post, a development of the Curtiss A-18 Shrike, would be along the lines of the Ki-96, a single-seat conventional twin. Another rather conventional twin that flew in 1941 was the MiG-5. The Pe-2 wasn't bad either.

In the above, I am not suggesting that all the types put forth were production-ready; they weren't. I am suggesting their designs could have been made to work. Had we abandoned the P-38, the logical things to purtsue in the USA at the time would have been an indigenous design, and I think a development along the lines of the Curtiss A-18 would have been not only possible, but also logical, and would have resulted in an acceptable aircraft in the timeframe required. Waiting for some of the non-US types to fly and then pursuing the design would seem to me to preclude deployment in 1942, but I could be wrong there.

Another things re. Lockheed 322 (the type British tested): the engine exhausts were collected to a single pipe, and then routed above the wing. That way plenty of the exhaust thrust was lost. So the plane with individual exhaust stacks, commonly found on most ww2 inline engined planes, would be able to attain the greater max speed, even if that's in 5-10 mph range. Further, the intake scoop was way shorter than one commonly found on P-40/-51, so IMO the ram effect was not being harvested as much as it was possible. The scoop was laying flush along with upper cowling, allowing the boundary layer to interfere.

GregP said:

The Grumman F5F could have been developed EASILY. It has potential, but was not pursued, but could have been.

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Indeed, it was a pretty innovative aircraft but the P-38 wasn't much less radical in design, and they performed on par with each other. It outscored all of the early WWII Allied fighters it was tested against, along with the XF4U Corsair prototype. Would've made a good plane for both USN as a carrier fighter and USAAC in the escort role, assuming its high altitude performance was up to snuff. A range of 1200 miles wasn't bad for an early WWII fighter and external stores could've expanded on that.

It didn't have nearly the payload or flexibility the P-38 had in the fighter-bomber role, though, and like the Whirlwind I'm not sure if the F5F's small airframe would've been able to take bigger engines without substantial reworking.

I would disqualify Grumman's F5F on aesthetic grounds. It must be one of the ugliest designs ever

Steve

I've started the new thread about the Grumman twins:

http://www.ww2aircraft.net/forum/aviation/xf5f-xp-50-how-good-they-really-were-34457.html

stona said:

I would disqualify Grumman's F5F on aesthetic grounds. It must be one of the ugliest designs ever

Steve

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The forward mounted wing is pretty weird but I think it looks sorta stubby and cute.

I've seen much uglier.

Ugly or not, I think the F5F is the only serious American competition for a high altitude interceptor during 1937 to 1938. F5F might have an edge in climb which is very important for this role.

It had great climb to 20,000ft (If that) then it crapped out. Service ceiling was 33,000ft. The engines were probably of the G-200 series and while they had 1200hp for take off they were down to 1000hp at 13,600ft or so not counting ram. And that is using the hi gear of a two speed supercharger. These engines were substitute engines when P&W stopped development of the two speed R-1535 engine. Trying to switch to two stage R-1830s would have added about 200lbs per engine, not including intercooler set up and bigger propellers.

I DID suggest a good alternative ... a redesigned, single-seat, Curtiss A-18 Shrike. It has great potential if done correctly, but was not actually done in real life. I thought the thread was to suggest alternative that could be popssible, not suggest only types that were built in quantity. Did I misunderstand?

If so, apologies; I have no suggestion at this time.

If not, what could be done with a redesign of the A-18 Shrike to make it a suitable WWII single-seat fighter?

I think a more modern airfoil for both the wing and the horizontal tail perhaps with maneuvering flaps, probably the turbo-supercharged Allisons, larger fin for the increased power, and a hard-hitting armament. I'd stick with conventional landing gear. I'd anticipate performance close to the P-38, perhaps with a bit more of an active takeoff and landing dance.

I truly don't see a better potential, and ultimately performing, twin engine fighter available in production in 1942 - which would have reached its potential far quicker had the USAAF not crashed the prototype.

XP-38 Drawings

The above link to a drawing shows six designs Kelly Johnson considered in response to Circular Proposal X-608.
Design #4 became the XP-38.

Design #5 looks curiously enough like the P-82 Twin Mustang.

GregP said:

If not, what could be done with a redesign of the A-18 Shrike to make it a suitable WWII single-seat fighter?

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Step 1, design a brand new, much smaller wing.
Step 2, design a new fuselage.
Step 3, design a new tail.
Step 4, use different engines and design new engine installation.
Step 5, design new armament package.
Step 6, Keep old landing gear???

tomo pauk said:

[...] insisting on the F6F even when the F4U looked like a world beater).

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I hate to break this to you but Roosevelt wasn't playing hypothetical games as you are here when he made the decision to go with the F6F over the F4U. The F4U had big problems in adapting to carrier-duty that still had to be worked out. While it was certainly designed as an Essex-class carrier-fighter, it was a complicated machine, and very difficult to manage, in combat, on a carrier, operating under those constraints. Grumman, on the other hand, had the F6F in concept well before Pearl, and, simply put, considering everything, was hands-down the right manufacturer for the job. I went over those reasons, therefore, in another thread, and I'm not going to repeat them, here, and throw off this technical discussion. But, that's the short of it, right there.

If I'm following your tirade right:
Since the F4U was proved as a troublesome CV bird (that would be in 1943) in service, Roosevelt (actually, the USN) decided in 1941 to "request Grumman to design an improved F4F- Wildcat" (pg. 558 in 'America's hundred thousand' book, which I'm conviced you've read, all 606 or 608 pages), that eventually became Hellcat.
You can re-read the complete sentence from the book , in order to understand why the Navy wanted the 'improved F4F-'.

Time to step down from the pedestal?

tomo pauk said:

If I'm following your tirade right:

Since the F4U was proved as a troublesome CV bird (that would be in 1943) in service, Roosevelt (actually, the USN) decided in 1941 to "request Grumman to design an improved F4F- Wildcat" (pg. 558 in 'America's hundred thousand' book, which I'm conviced you've read, all 606 or 608 pages), that eventually became Hellcat.

You can re-read the complete sentence from the book , in order to understand why the Navy wanted the 'improved F4F-'.

Time to step down from the pedestal?

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That's childish. And, if I might add, it's unnecessarily provocative. There, is that the level of discourse you're accustomed to? Remain in your ignorance, then, see if I care.

For the rest, for those of you who may wish to understand, consider this. Coral Sea. No F4U. Midway. No F4U. Why? Chance-Vought still hadn't resolved the issues attendant to fitting that complicated aircraft to carrier-duty, that was the reason for that. On the other hand, Grumman had already had all those carrier-constraints worked out in the F4F, and they had the F6F in concept, ready to go forward on it, as early as 1941. Again, I had already went over much of this in another thread, and I'm hardly inclined to repeat it, here, and throw off this hypothetical technical discussion, especially in view of the immature way in which I'm now being received. But, that's the way it was. The Navy had nothing against the F4U. It was its second commissioned monoplane carrier-fighter. For the reasons aforestated, it simply wasn't ready for prime time. And, that's just how it was.

The intention was to 'provocate' the usage of sources, but it was in vain.
You don't check Wikipedia, but demand that your posts are read and understand 110%. You claim that Roosevelt knew that Corcair's service troubles, and give a get-go for the F6F, yet, when challenged by a reliable source, decided to claim foul on my behalf, rather than to post something to back your claim. Now you claim that F4U was the second monoplane fighter commisioned by the USN -again, not true.

Further, when quoting someone's posts, cutting the sentences in half and then making the case about that is not going to cut it (no pun intended).

The scenario does not flatly assume that P-38 was removed from the front, but that USAF goes for an 'insurance' against a possible P-38 major mishap (be it an overlooked construction miscalculation, or maybe difficulties in production). USN took similar path (encouraging Grumman to perfect the F4F in case F2A gets into troubles; insisting on the F6F even when the F4U looked like a world beater).

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My invitation: in case you have something, well backed by sources, that would make the bolded sentence wrong, I'll delete it.

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Coral Sea. No F4U. Midway. No F4U. Why? Chance-Vought still hadn't resolved the issues attendant to fitting that complicated aircraft to carrier-duty, that was the reason for that.

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No, it was not the reason. The reason was that, prior June 31th 1942, Vought has produced 4 (four) F4Us. Complicated it was? Not really.

The another alternative, a more unorthodox one, could be a 'US Pfeil', or a plane with two engines arranged in push-pull configuration. The V-1710 was tried in a pusher layout prior the war (the Bell 'Airacuda' was an user of the D series Allisons), the Allison company experimenting a lot with remote installations. The weight of an engine installation of the single stage V-1710 was 2500-2600 lbs, and we can compare that with P-47D, whose engine installation weighted 4300 lbs; the 2 stage R-2800 was some 3900-4000 lbs.
So we have 5000 (early engine models) to 5200 (late models) for 2 V-1710s. The P-38's installation went to 6300 lbs in -J model. So we save at least 1000 lbs vs. the P-38. We also save on drag, as it was demonstrated on Do-335 vs. Me-410 (same/similar engines, but the Dornier was way faster).
With less weight to cater for, the wing can be smaller, so both weight and drag are again decreased. Six HMGs, with 400 rpg? The landing gear can be of a lower weight, too. So all in all, the weight can be shaved for some 1200-1300 lbs vs. the P-38.
The layout would be Pfeil-ish: engine, pilot, radio, fuselage fuel tank, engine, tail. The wing can be in low position, inboard housing the fuel tanks and main U/C gear, outboard being the HMGs and ammo.

tomo pauk said:

The intention was to 'provocate' the usage of sources, but it was in vain.
You don't check Wikipedia, but demand that your posts are read and understand 110%. You claim that Roosevelt knew that Corcair's service troubles, and give a get-go for the F6F, yet, when challenged by a reliable source, decided to claim foul on my behalf, rather than to post something to back your claim. Now you claim that F4U was the second monoplane fighter commisioned by the USN -again, not true.

Further, when quoting someone's posts, cutting the sentences in half and then making the case about that is not going to cut it (no pun intended).



My invitation: in case you have something, well backed by sources, that would make the bolded sentence wrong, I'll delete it.

edit:>


No, it was not the reason. The reason was that, prior June 31th 1942, Vought has produced 4 (four) F4Us. Complicated it was? Not really.

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OK, that's better. Now I understand what your beef is. Again, I don't want to take this hypothetical discussion off track and come under fire from you for that like others here have. But to address your issue on my sourcing, let me put it this way. Your sources are published materials, my sources are unpublished materials. Your sources are persons with primary and secondary knowledge, my sources are persons with primary and secondary knowledge. Your knowledge is based on what you read from said sources, my knowledge is based on what I discussed with said sources. Let me ask you something, and think about this hard. What makes your sources more creditable than mine? What makes your knowledge taken from said sources better than mine? Please don't tell me it's because your sources are published and mine aren't, because I'm just not going to swallow that.

I'm out of the office right now and on an iPhone and this is a pain in the ass typing on one of these things so you'll excuse me for being brief, but I'll just say this. The F4F was a monoplane version of the F3F, basically, and together with the F4U, those were the only two monoplane fighters the Navy had approved before the F6F. On the F4U, specifically, it was on the drawing board for a very long time, and it had problems, especially in terms of fitting it to carrier-operations under combat conditions. I'll go over those apprehensions relative to the F4U and why Roosevelt went with the F6F in more detail when I get to a computer, if you think it's necessary, and you want it in this thread, no problem. For now, however, this will just have to hold you.