USAAC/AAF being much improved in 1938-42?

[swampyankee]

Since the commercial market wasn't interested in liquid-cooled engines and in the early 1930s, with the introduction of NACA cowlings (note both the DC-1 and Boeing 247 had their first flights in 1933, which meant their design was started by 1931, at the latest), the drag advantage of liquid-cooled engines was largely illusory, at least until the introduction of plate-fin radiators and proper ducting systems, Allison had really one customer: the US government. The V-1710 was originally funded in 1929 and first flew in 1936, although it probably first ran in 1932 or 1933. The largest problem was that the USAAC was too focused on turbo-chargers which, while better, were also bulky and farther from operational status. Because of this, Allison's mechanical superchargers had detail design issues which impaired their performance and reduced their efficiency.

Overall, however, I don't think the P-40 could be much improved without the use of a full-scale wind tunnel, as was done with the F4F. The USAAC had other fighters in service or nearing production, but none of these were better. (some with argue the P-39 was, but I disagree: the mid-mounted engine caused a lot of compromises in flight characteristics that could not be overcome. The USAAC needed a fighter with Bf109-like range about as much as it needed triplanes)

The real area for improvement was, in my opinion, tactical support of ground forces. Here, interservice (or even intra-service) rivalry was major problem. The USMC had been developing tactical support of ground forces by aircraft for at least a decade (see: dive bombing, for example) and the related issues of ground-air communication; the USAAC should have found out what worked for a service with its headquarters a few miles down the road. I don't know what wouldn't be built (there were a whole bunch of O-nn aircraft which turned out to be militarily useless, e.g., the O-43. I'd start with not building those) and what would, but I suspect the biggest problem wasn't hardware, but doctrine.

So, my USAAC development would be:

• Keep the OTL fighters on-stream. The only (doctrinal) change would be to allow drop tanks (these were not new technology!) and increased bomb loads on "pursuit" aircraft.
• Introduce a dedicated CAS aircraft. The A-36 was perfect, but didn't exist yet. The Hawk 75K variant may be a good starting point, though.
• Try to get a second liquid cooled engine source. If V-12s are so great, don't depend on one vendor! There are two companies making big radials, but they can thrive on civil contracts. Nobody except the military will buy V-12s for aircraft.
• Pay very careful attention to what was going on in China and the Spanish Civil War. Both Japan and Germany were acting in ways that could threaten US interests and both were producing leading-edge combat aircraft and tactics. I realize isolationism was a very powerful political position, it didn't preclude actually paying attention to the rest of the world.

 

[tomo pauk]

...
Overall, however, I don't think the P-40 could be much improved without the use of a full-scale wind tunnel, as was done with the F4F. The USAAC had other fighters in service or nearing production, but none of these were better. (some with argue the P-39 was, but I disagree: the mid-mounted engine caused a lot of compromises in flight characteristics that could not be overcome. The USAAC needed a fighter with Bf109-like range about as much as it needed triplanes)

Yes, P-39 was never an answer to the AAF prayers.
The P-40 was no less streamlined than Spitfire, Fw 190, let alone Zero, F4F or G.55. No need for wind tunnel that much (the historical P-38 needed it badly, though), what was dearly needed was a far better engine than the plain-vanilla V-1710 of 1940-42.

 

[Kevin J]

Yes, P-39 was never an answer to the AAF prayers.
The P-40 was no less streamlined than Spitfire, Fw 190, let alone Zero, F4F or G.55. No need for wind tunnel that much (the historical P-38 needed it badly, though), what was dearly needed was a far better engine than the plain-vanilla V-1710 of 1940-42.

If you're going to put the Merlin into an interceptor fighter then surely the Cobra is the better candidate as it's smaller, lighter and faster than the Warhawk.

 

[tomo pauk]

If you're going to put the Merlin into an interceptor fighter then surely the Cobra is the better candidate as it's smaller, lighter and faster than the Warhawk.

Two things might interfere:
- Someone needs to redesign the crankcase of a Merlin, with separate reduction gearing, so the engine can fit without the extension shaft going through the pilot. It probably can be done, the V-1650-5 was supposed to feature remote reduction gearing, but that was in design phase in late 1943/early 1944 historically, and I don't know whether there was any -5 produced.
- P-51 is an even better candidate.

 

[Kevin J]

Two things might interfere:
- Someone needs to redesign the crankcase of a Merlin, with separate reduction gearing, so the engine can fit without the extension shaft going through the pilot. It probably can be done, the V-1650-5 was supposed to feature remote reduction gearing, but that was in design phase in late 1943/early 1944 historically, and I don't know whether there was any -5 produced.
- P-51 is an even better candidate.

I agree that for the two stage Merlin, the Mustang. The single speed Merlin, the Cobra or Tomahawk. The 2 speed Merlin, the Kittyhawk.

 

[tomo pauk]

I agree that for the two stage Merlin, the Mustang. The single speed Merlin, the Cobra or Tomahawk. The 2 speed Merlin, the Kittyhawk.

I won't rain on your parade.

 

[The Basket]

The main issue is that if the Americans made a Spitfire then they could have sold that in the late 30s to a fearful Europe.

P-40 and P-36 were actually sufficient at Pearl Harbour and even F-22 wouldn't have stopped Pearl Harbour if they burning on the tarmac.

 

[tomo pauk]

Any suggestions for the bomber fleet?

 

[Shortround6]

Any suggestions for the bomber fleet?

Well, the medium bombers don't need a lot of help, counting the A-20 as a medium bomber here
While not perfect they had most of the others beat.

The B-17 and B-24 with their turbos fall into a weird area, they make as much power high up with their "1200" engines as many other 1400-1700hp for take off engines do once they are at over 20,000ft. Ripping the turbo R-1830s out of a B-24 and sticking in non turbo R-2600s gets you off the runway with a much bigger load but doesn't do much for speed at over 20,000ft.

 

[Kevin J]

Any suggestions for the bomber fleet?

I don't see how you could beat the bombers that they had, with the possible exception of the British Mosquito, but being wooden, that's going to restrict you to operating in temperate climates, so that would mean operating restrictions in the USA.

 

[Shortround6]

I don't see how you could beat the bombers that they had, with the possible exception of the British Mosquito, but being wooden, that's going to restrict you to operating in temperate climates, so that would mean operating restrictions in the USA.

Even if the glue problem could have been (or was) solved or if you built a metal equivalent, the problem with a Mosquito like aircraft in 1938-42 is the engines.
The Mosquito was originally a 1000lb bomb load aircraft, perhaps in part due the size of the british bombs. However it's engines also grew in power with very little gain in weight (until the two stage engines) as the boost limits were pushed. A 1941 Mosquito with 9lb boost limit?
An American Mosquito, if using Packard Merlins won't show up in service until the spring or summer of 1942 using V-1650-1 engines and then at the cost of two P-40Fs for every such plane. If using Allisons such a plane could be built earlier but performance is questionable. You have 150hp less per engine and compared to an A-20 you have 900hp less for take off or about 72% of the power. Things get a lot closer at 12-14,000ft and the Allisons are more streamline. You could try turbo Allisons and pick up a bit at sea level and a lot at higher altitudes but there aren't a lot of turbos to go around and in 1940-1941 there weren't a lot of Allisons either, in 1942 they built more Allisons most months than they did in all of 1940, 1941 saw 6400 Allisons built and 1942 saw 14,900. US turbo installations weren't as well sorted out in 1941-42 as they would be later.
An A-20 with Allisons would be an interesting plane, but would it really be any better than the existing A-20s?

 

[swampyankee]

I don't see how you could beat the bombers that they had, with the possible exception of the British Mosquito, but being wooden, that's going to restrict you to operating in temperate climates, so that would mean operating restrictions in the USA.

One other barrier to a wooden bomber was that there had been a number of structural failures in wooden commercial aircraft, so there were constraints on wood use in karge aircraft. While these rules didn't affect the military, it would tend to mean that the companies making bombers would be leery of using wood.

 

[tomo pauk]

Even if the glue problem could have been (or was) solved or if you built a metal equivalent, the problem with a Mosquito like aircraft in 1938-42 is the engines.
The Mosquito was originally a 1000lb bomb load aircraft, perhaps in part due the size of the british bombs. However it's engines also grew in power with very little gain in weight (until the two stage engines) as the boost limits were pushed. A 1941 Mosquito with 9lb boost limit?

360+ mph max, 330 mph cruise at max weak mixture setting? Not unlike what the bombed-up B.IV D.K.290/G did here on +8.9 psi and +4 psi, respective for max speed and cruise.

An American Mosquito, if using Packard Merlins won't show up in service until the spring or summer of 1942 using V-1650-1 engines and then at the cost of two P-40Fs for every such plane. If using Allisons such a plane could be built earlier but performance is questionable. You have 150hp less per engine and compared to an A-20 you have 900hp less for take off or about 72% of the power. Things get a lot closer at 12-14,000ft and the Allisons are more streamline. You could try turbo Allisons and pick up a bit at sea level and a lot at higher altitudes but there aren't a lot of turbos to go around and in 1940-1941 there weren't a lot of Allisons either, in 1942 they built more Allisons most months than they did in all of 1940, 1941 saw 6400 Allisons built and 1942 saw 14,900. US turbo installations weren't as well sorted out in 1941-42 as they would be later.
An A-20 with Allisons would be an interesting plane, but would it really be any better than the existing A-20s?

An A-20 with turboed V-1710s would've been excellent at least for the tasks in Asia/Pacific - faster than the historical A-20, and with better mileage.
We can recall that DB7 was making 300+ mph at 2x900 HP at 12000 ft, bomb load 2000 lbs, 2x1050 HP for take off. A V-1710 of the era, like the C15 version, will not offer just better streamlinig and better exhaust thrust, but also much better power above 10000 ft.

The early Pe-2 was good for 2200 lbs of bombs, 320-330 mph on 1050 HP at 13100 ft, 1100 HP for take off.
Bf-110C, Ju-88A1 and Do-215 also offered useful bombload on 1100-1175 HP for take off (even though bomb-bays there were between non-existent and restricted).

 

[pinsog]

Give the P36 a 2 speed P&W 1830-33, it would boost top speed up to around 325 mph at 17,000 feet as well as adding to climb rate above 15,000 feet as well.

Build the P43 Lancer with actual fuel tanks instead of wet wings and keep them all for US use. It would be a great to have 1 fighter that is faster and can get above a Zero until the P38 finally shows up.

 

[tomo pauk]

Give the P36 a 2 speed P&W 1830-33, it would boost top speed up to around 325 mph at 17,000 feet as well as adding to climb rate above 15,000 feet as well.

The P-40 (no letter) was good for perhaps 350 mph at 17000 ft?
data sheet

 

[pinsog]

The P-40 (no letter) was good for perhaps 350 mph at 17000 ft?
data sheet

We have P36's in the inventory so we might as well use them. P40 would be faster, P36 should climb and turn better as well as being easier to maintain. Deploy both of them in the Pacific to the same spots. Maybe P36 gives top cover to P40's, P43 above both of them.

 

[tomo pauk]

We have P36's in the inventory so we might as well use them. P40 would be faster, P36 should climb and turn better as well as being easier to maintain. Deploy both of them in the Pacific to the same spots. Maybe P36 gives top cover to P40's, P43 above both of them.

What level of firepower, protection and fuel tankage should we envision for P-36 and P-40 in 1941-42?

Now that we're at American fighters - what might be the proposals for an alternative 2-engined fighter, a role historically took by P-38? Provided Lockheed goes twin, of course.

 

[pinsog]

What level of firepower, protection and fuel tankage should we envision for P-36 and P-40 in 1941-42?

Now that we're at American fighters - what might be the proposals for an alternative 2-engined fighter, a role historically took by P-38? Provided Lockheed goes twin, of course.

P36 and P40 4 50's with 200 rpg, back armor and self sealing tanks.

Alternate to P38, that's easy for me, no secret I'm a fan of the Grumman F5F. Build it instead of the Wildcat.

Long nose and long engine nacelles 4 50's 400 rpg with 279 gallons of fuel comes in at 10,900. Add turbo chargers 500 pounds
Add 150 pounds of armor
Add 150 pounds for self sealing tanks. Lowering fuel down to 250 gallons

Weight is now 11,700

Add a 75 gallon tank to each outer wing, weight comes up to 12,000, fuel brings weight up to 12,900.
That's 400 gallons of fuel and it weighs 1,500 pounds less than an early P38 with 300 gallons.
Speed should be same as early P38 but with better climb, better dive and more maneuverable(weighs 1,500 pounds less, has 100 more hp, was dived vertically to 505 mph)
and it's carrier capable.

 

[Kevin J]

P36 and P40 4 50's with 200 rpg, back armor and self sealing tanks.

Alternate to P38, that's easy for me, no secret I'm a fan of the Grumman F5F. Build it instead of the Wildcat.

Long nose and long engine nacelles 4 50's 400 rpg with 279 gallons of fuel comes in at 10,900. Add turbo chargers 500 pounds
Add 150 pounds of armor
Add 150 pounds for self sealing tanks. Lowering fuel down to 250 gallons

Weight is now 11,700

Add a 75 gallon tank to each outer wing, weight comes up to 12,000, fuel brings weight up to 12,900.
That's 400 gallons of fuel and it weighs 1,500 pounds less than an early P38 with 300 gallons.
Speed should be same as early P38 but with better climb, better dive and more maneuverable(weighs 1,500 pounds less, has 100 more hp, was dived vertically to 505 mph)
and it's carrier capable.

But it only arrives at the same time as the Corsair and requires twin. Engine training, so no.

 

[Kevin J]

We have P36's in the inventory so we might as well use them. P40 would be faster, P36 should climb and turn better as well as being easier to maintain. Deploy both of them in the Pacific to the same spots. Maybe P36 gives top cover to P40's, P43 above both of them.

I think you mean P-40 gives top cover to P-36 allowing the later to go after the bombers. There's only a couple hundred 2 stage R-1830's built by end 1941, but hundreds of Packard Merlins.