ALternatives for the P-38?

[stona]

Imagine the Welkin's Merlin power at mid-to-high altitude and larger fuel stores

The Welkin was a poor aircraft. When the RAF tried to test it against a Mosquito they initially failed to gather any useful data due to its lack of manouevrability. Aileron control was very poor at all speeds and altitudes and compressibility effects caused pitching at speeds corresponding to Mach 0.65 which meant it couldn't follow anything in a dive.There were also problems with high speed stalling and complete ineffectiveness of the elevator. In single engined flight a very severe rudder oscillation would occur.
Later tests,at high altitude,concluded that a Welkin could attack a heavy bomber but that a single engined fighter would easily out manoeuvre it.Not a good aeroplane and a dubious starting point for something to match the P-38.

The Vickers 432 might be a better starting point,though it too had plenty of problems to sort out.

Steve

 

[ShVAK]

All of the Welkin's problems stemmed from its long U-2 like wing, which my hypothetical design addresses. My P-38 alternative would be a Welkin/Whirlwind hybrid. This is a "what if," not the actual Welkin as designed which was a plane in search of a role when the LW abandoned most of its high altitude bombing operations over Britain.

 

[stona]

All of the Welkin's problems stemmed from its long U-2 like wing,

Some,even most,of them did.

I appreciate that this is a what if,but your starting point (you said "similar" to a Welkin) is an aircraft that had many problems. To design these out,including a new wing might well be a greater challenge than simply going back to the drawing board.

There were other twin engined British prototypes which might offer a better alternative.

Steve

 

[ShVAK]

Fair enough.

The Vickers Type 432 looks very similar to the Mosquito, to the point of making me question if it's even worth choosing over de Havilland's wooden wonder. Maybe a license-built American version of the Mosquito specialized as an escort/heavy fighter would be the way to go over the P-38?

 

[stona]

The Vickers Type 432 looks very similar to the Mosquito,

Nearly all British twin engined designs of the era do (maybe not the Miles M.39)

I honestly don't believe that any of the putative British twin engined types offered anything better than the P-38 in the heavy fighter/long range,escort role.

Maybe we need to seek inspiration elsewhere.As a what if,something along the lines of the Fw 187,obviously Merlin powered,might fit the bill.

Throughout the war in the ETO twin engined types struggled to hold their own against single engined opposition. The P-38 struggled less than many.

Steve

 

[ShVAK]

A Merlin or Allison-powered Fw 187 might work nicely, but I'm sure getting the design details out of Nazi Germany would've been some hassle compared to working with Britain.

In the end the advantages posed by most of these designs, if any, would be miniscule compared to the P-38 in the role the USAAC wanted to fill. I think if the compressibility issues had been discovered and dealt with earlier the Lightning would've been regarded in a more positive light than it was. The reliability of the turbo-supercharged Allisons were spotty at the time but compared to early versions of the Napier Sabre or the R.R. Vulture it was a far better engine, and the problems were eventually worked out (as were most of the Sabre's).

 

[Shortround6]

The problem is that to truly be a competitor for the P-38 work had to started not long after the P-38 was started. Without a time traveler to advise them what were the promised available engines going to be? and how would they affect the design?

When does R-R even promise the Merlin XX? the Merlin 61 is way too late to design around for a 1942 fighter debut.

One might assume that engines were running on test stands 1 to 2 years before they made operational debuts so at what point does the airframe design staff PICK their choice of engine?

 

[stona]

Something like the Gloster F.9/37. First flew in 1939 with Bristol Taurus engines. A later prototype was powered by RR Peregrines and was underpowered,Merlins remane a what if.It never entered production and was superceded by the Mosquito and Beaufighter.

It had more chance of development than something like the awful Bristol Buckingham that actually did enter series production!

Steve

 

[davebender]

getting the design details out of Nazi Germany would've been some hassle compared to working with Britain.

The USA won't get much cooperation out of 1937 Britain either. Not after the Smoot-Hawley Tariff followed by British repudiation of $4.4 billion owed to the American Government.

 

[Shortround6]

The Gloster F.9/37 shows some of the problem. It is a larger, higher drag airframe than the P-38 yet it is lighter with 'as flown' engines. Unless it was designed for bigger engines from the start and just using the Taurus and Peregrines as temporary engines it may need a fair amount of beefing up to mount Merlins ( or a crap load of ballast, those engines are as far forward as you can get), even with equivalent engines to the P-38 ( or even Merlin XX) it will be slower due to the larger wing and fuselage?

 

[stona]

even with equivalent engines to the P-38 ( or even Merlin XX) it will be slower due to the larger wing and fuselage?

According to the A+AEE it managed 360 mph at 15,000 ft with the 1,050hp version of the Taurus,the T-S(a)TE.1. With the 885hp Peregrine it only managed 330 mph at the same altitude.

I think that you are quite correct,it would be considerably slower than a P-38 even with a couple of 1500hp engines bolted on.

Steve

 

[ShVAK]

The USA won't get much cooperation out of 1937 Britain either. Not after the Smoot-Hawley Tariff followed by British repudiation of $4.4 billion owed to the American Government.

By March 1941 the Brits would've been more pliable.

If several thousand Mosquito could be churned out by Blitz-stricken Britain from 1941 to the end of the war, I'm sure we could do the same with an Allison-powered variant (with handed engines) on the other side of the pond if the UK government was willing to supply the necessary tooling. Whether it was worth it to do all this rather than just stick to the P-38 is another matter.

 

[davebender]

Are you suggesting the P-38 aircraft program should be cancelled after 4 years of development, just as mass production was beginning?

 

[ShVAK]

Well in this hypo the P-38 wouldn't have been scrapped entirely--either placed on the back burner if it proved too troublesome or the Allison Mosquito would be the alternate.

Maybe thousands was stretching the point. We could build 300-600 of the alternate design without impacting much else, and more if it turned out to be better for the job than the P-38.

 

[davebender]

During 1937?

The Mosquito was a light bomber. If approved the U.S. built Mosquito would be competing against A-20 and A-26 light bombers. Not P-38 fighter aircraft.

 

[stona]

The Mosquito was a light bomber

That was one of its roles. That's like saying the Ju 88 was a dive bomber because it was designed to do that.

Steve

 

[tomo pauk]

Alrighty then, here is one of my proposals:
A twin of the 'classic' layout, akin to the Falke, Whirlwind, or Hornet, but of a mid-wing configuration. Armament layout similar to the Bf-110, or armed Mossie: 4 HMGs inn the nose, 2 cannons under and slightly aft (or another 4 HMGs there). Turbo V-1710, installation similar to the P-40 (so, with both oil and Prestone radiators in front), inter cooler in the front of the leading edge. Turbine at the aft of the nacelle, the axle being in parallel with aircraft axle, so we can harvest some exhaust thrust. Pilot's cabin above the leading edge, so the addition of the second crew member does not mess the CoG.
Thinner wing, with Fowler flaps, fuel tanks inboard of the nacelle, protruding into the fuselage (some 200-250 gals there, total). Another fuel tank in the lower hull ( some 150 gals there). Two attachment points inboard. As available engine power increases from 1943, two outboard pylons, as well as another 100 gal tanks outboard of nacelles.
The low-risk version (engines from the P-40, 2 nose HMGs deleted to compensate for deletion of turbines; the lack of inter cooler serves for the same purpose).

 

[wuzak]

By March 1941 the Brits would've been more pliable.

If several thousand Mosquito could be churned out by Blitz-stricken Britain from 1941 to the end of the war, I'm sure we could do the same with an Allison-powered variant (with handed engines) on the other side of the pond if the UK government was willing to supply the necessary tooling. Whether it was worth it to do all this rather than just stick to the P-38 is another matter.

Arnold saw the prototype Mosquito and was hugely impressed. He requested and received plans to take back to teh US for potential licence production. He gave them to 5 companies - Beech, Curtiss-Wright, Fleetwings, Fairchild and Hughes.

Beech said:

It appears as though this airplane has sacrificed serviceability, structural strength, ease of construction and flying characteristics in an attempt to use a construction material which is not suitable for the manufacture of efficient airplanes.

The Mosquito was never really a contender for the P-38's fighter role.

 

[davebender]

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.

 

[Shortround6]

A twin of the 'classic' layout, akin to the Falke, Whirlwind, or Hornet, but of a mid-wing configuration. Armament layout similar to the Bf-110, or armed Mossie: 4 HMGs inn the nose, 2 cannons under and slightly aft (or another 4 HMGs there). Turbo V-1710, installation similar to the P-40 (so, with both oil and Prestone radiators in front), inter cooler in the front of the leading edge. Turbine at the aft of the nacelle, the axle being in parallel with aircraft axle, so we can harvest some exhaust thrust. Pilot's cabin above the leading edge, so the addition of the second crew member does not mess the CoG.
Thinner wing, with Fowler flaps, fuel tanks inboard of the nacelle, protruding into the fuselage (some 200-250 gals there, total). Another fuel tank in the lower hull ( some 150 gals there). Two attachment points inboard. As available engine power increases from 1943, two outboard pylons, as well as another 100 gal tanks outboard of nacelles.
The low-risk version (engines from the P-40, 2 nose HMGs deleted to compensate for deletion of turbines; the lack of inter cooler serves for the same purpose).

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

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.