USAAC/AAF being much improved in 1938-42?

[tomo pauk]

Same drill as before - a much improved USAAC/AAF between 1938 (where the canges start at drawing boards and, possibly, wind tunnels and test benches) and 1942. What improements can be gotten using technology, aerodynamics, electronics and fuels of the day? Organization and logistics changes? Improvements in 'producibility' category and ease of use/maintenance? Guns/bombs/rockets?

 

[Kevin J]

Same drill as before - a much improved USAAC/AAF between 1938 (where the canges start at drawing boards and, possibly, wind tunnels and test benches) and 1942. What improements can be gotten using technology, aerodynamics, electronics and fuels of the day? Organization and logistics changes? Improvements in 'producibility' category and ease of use/maintenance? Guns/bombs/rockets?

You need a lot more P-40F being produced. AFAIK they all got sent to the MTO. Alternately, you need a lot more 2 stage R-1830's being produced installed in Vultee Vanguards then sent to the PTO.

 

[Admiral Beez]

Same drill as before - a much improved USAAC/AAF between 1938 (where the canges start at drawing boards and, possibly, wind tunnels and test benches) and 1942. What improements can be gotten using technology, aerodynamics, electronics and fuels of the day?

Packard V-1650 first run in 1938, not summer 1941. Mass production begins summer 1939.

You need a lot more P-40F being produced.

That should do it.

 

[swampyankee]

Overall, I think the USAAC/USAAF was doing pretty well, except for close-support, which was more a problem of practice and doctrine than hardware, and liaison/observation aircraft.

Because there was a massive commercial aviation industry, which made what were easily the most advanced passenger aircraft, the USAAC/USAAF could easily get just about all the transport aircraft it would need pretty much off the shelf.

 

[tomo pauk]

Overall, I think the USAAC/USAAF was doing pretty well, except for close-support, which was more a problem of practice and doctrine than hardware, and liaison/observation aircraft.

Fighter aircraft might use improvement in the specified era.

Because there was a massive commercial aviation industry, which made what were easily the most advanced passenger aircraft, the USAAC/USAAF could easily get just about all the transport aircraft it would need pretty much off the shelf.

Agreed.

 

[Admiral Beez]

When the Air Ministry showed no interest in Frank Whittle's turbine in the 1930s, have him join the US effort. p-80 Shooting Stars at Pearl Harbour.

 

[Shortround6]

You need a lot more P-40F being produced. AFAIK they all got sent to the MTO. Alternately, you need a lot more 2 stage R-1830's being produced installed in Vultee Vanguards then sent to the PTO.

Packard V-1650 first run in 1938, not summer 1941. Mass production begins summer 1939.

Packard built 45 V-1650 engines in 1941, 26 of them in December. In April of 1942 they built 505 and in July they were at 800 a month. Without an actual miracle ( parting clouds, shining lights and voices from on high) things weren't going to go much faster.

As for A Packard V-1650 in 1938?
It would have been a Merlin III at best, not a Merlin XX.
Stuffing a Merlin III into a P-36 airframe might not give you quite the world beating performance some people imagine.

 

[Admiral Beez]

Packard built 45 V-1650 engines in 1941, 26 of them in December. In April of 1942 they built 505 and in July they were at 800 a month. Without an actual miracle ( parting clouds, shining lights and voices from on high) things weren't going to go much faster.

Not a miracle. Just have Packard start earlier. Rolls Royce first ran the Merlin in 1933. Let's get Packard making their first running engine six years later in 1939. Seems doable.

 

[swampyankee]

Not a miracle. Just have Packard start earlier. Rolls Royce first ran the Merlin in 1933. Let's get Packard making their first running engine six years later in 1939. Seems doable.

It's certainly physically possible, but would the UK and Rolls-Royce consider allowing it?

 

[Jugman]

It's certainly physically possible, but would the UK and Rolls-Royce consider allowing it?

No because Packard TRIED to get a license to build the Merlin in 1938 and RR flat out refused.

I don't think people appreciate the greatest advantage the Merlin had over the Allison. And that is it was in production for roughly three years before the Allison. Having three years to sort out production and service teething troubles would've been a huge help.

 

[Shortround6]

Not a miracle. Just have Packard start earlier. Rolls Royce first ran the Merlin in 1933. Let's get Packard making their first running engine six years later in 1939. Seems doable.

The Merlin did not spring into being in 1933 all set to go.

The Prototype engines, two built and the first one run in Oct 15th 1933 had quite a number of problems and differed considerably in construction from later Merlins. One piece block and cylinders for one thing. considerable cracking. lots of problems with the cooling system. It wasn't flown until Feb 21st 1935 which was a busy year for the Merlin.

Two more prototype engines are built at the end of 1934/ beginning of 1935 the Merlin B. First run in Feb 1935. Flat cylinder heads are repaced by "ranp" or semi-penthouse heads with valves at a 45 degree angle. more problems with block cracking and they decide to go with separate cylinder castings and an upper crankcase casting in the next version.

We are now to the Merlin C, first run in April 1935, now has detachable cylinder heads, It is first flown in the Hawker Hurricane prototype, the engine is replaced 3 times as succeeding engines all suffer mechanical failures. It fails a 50 hour civil type test and it is decided to change from the composite water and steam to a 100% glycol system.

The Merlin D seems to have disappeared so the next engine is the Merlin E. It passes a civil type test in Dec 1935 but fails a military 100 hour test in March of 1936.

Itis followed by the Merlin F (later called the Merlin I) with more minor changes but still with the ramp head. The engine passes a reduced type test and is put into small scale production ( 25 built 1935-37) due to the escalating tensions with Germany. Merlin I's are built to the tune of 172 engines powering early Battles, the fairey P.4/34 and the Hawker Henley.

This is overlapped by the Merlin G (later the Merlin II) which goes back to the flat head and one piece cylinder block. It passes a type test in Oct 1936. There are 1283 Merlin IIs built from 1937 to 1939. Early Merlins, including the II suffered from piston ring flutter at maximum supercharge. This lead to rings breaking up, seizing and rapid total engine failure.

Finally with some changes, the Merlin III comes on line in 1938.
Now at what point does Packard swoop in and sign a licence agreement and start churning out Merlin's and of which type?

the Merlin IV, V, VIII and X all make their appearance in 1938 All (?) use pressure cooling with a 70/30 mix of water and glycol.

the Merlin XII shows up in late 39 or early 40 and the 45 shows up in 1940 with the Hooker modified supercharger followed by the Merlin 45 in 1941.

Since it took Packard about one year from the signing of the contract to first handful of engines during the war the chances of them beating that time scale by any significant amount in peace time is about zero. You want even a few dozen engines in 1939 you better have signed the deal in the middle of 1938.

 

[Kevin J]

I like the idea of the Gloster E. 28/39 being available at Pearl Harbour, now that would have come as a nasty surprise for the IJN, its four LMG should have been sufficient in dealing with their aircraft.
Also, the Merlin X built under licence and installed in the Tomahawk from day 1, and all Kittyhawks having Merlin XX's.

 

[tomo pauk]

A P-40B airframe, but with Merlin III/X/XII engine is a 360+ mph aircraft, that can actually climb well above 15000 ft. Not too shabby for 1940-42, when compared what Americans actually used and what they were against.

Engine situation can also be improved with Allison not tasked with making V-1710 to be available in myriad of versions (also no V-3420). Like, no pusher version - the Airacuda is also killed before the 1st ink is on the paper. Use the time & resources to bring the S/C gearing to 9.6:1 for altitude-rated engines so the altitude power is somewhat improved before 1942, in a reliable & producible manner. Install the resulting engine(s) on P-51/40/39.
Next improvement is a 2-stage V-1710, hopefully this time with intercooler.

 

[Shortround6]

Please remember that 1939-1941 US 100 octane fuel is not the Same as British 1939-1941 100 Octane fuel. 12lbs boost may not be possible with American fuel?

P-40B had an engine good for 1040hp at over 14,000ft, a 1030 hp engine at 16,250 isn't going to show a huge improvement.

P-40B performance figures are for a 6835lb plane, unfortunately, even though that is 490lbs under normal gross weight. Normal gross weight is with 120 US gallons of fuel.

Sticking a Merlin III or XII in a 7300lb plane is not going to get you an American Spitfire. Cutting the .50 cal ammo to 200rpg and wing gun ammo to 400 RPGs is only going save about 120lbs. Take out another 15 gallons of fuel, for another 90bs, use only 160lb pilots?

 

[tomo pauk]

Please remember that 1939-1941 US 100 octane fuel is not the Same as British 1939-1941 100 Octane fuel. 12lbs boost may not be possible with American fuel?

In 1939-40 and on American 100 oct fuel, a Merlin III will beat the V-1710 due to a bigger S/C and lower CR.

P-40B had an engine good for 1040hp at over 14,000ft, a 1030 hp engine at 16,250 isn't going to show a huge improvement.
P-40B performance figures are for a 6835lb plane, unfortunately, even though that is 490lbs under normal gross weight. Normal gross weight is with 120 US gallons of fuel.
Sticking a Merlin III or XII in a 7300lb plane is not going to get you an American Spitfire. Cutting the .50 cal ammo to 200rpg and wing gun ammo to 400 RPGs is only going save about 120lbs. Take out another 15 gallons of fuel, for another 90bs, use only 160lb pilots?

I've never said it will be a huge improvement, just that it will add perhaps 10 mph and enable it to climb better at higher altitudes. I'm not after the American Spitfire, but after improving the odds of American and Allied airmen in early 1940s.

 

[Shortround6]

In 1939-40 and on American 100 oct fuel, a Merlin III will beat the V-1710 due to a bigger S/C and lower CR.

Not by much, the same basic supercharger used on the -33 Allison was used on the later ones that got 1150hp at over 15,000ft. A usable set of 9.60 gears (or something in between the 8.77 and 9.60 gears) would have given the 1040 hp a few thousand feet higher (at the cost of power lower down).

I've never said it will be a huge improvement, just that it will add perhaps 10 mph and enable it to climb better at higher altitudes. I'm not after the American Spitfire, but after improving the odds of American and Allied airmen in early 1940s.

Adding 100-200fpm to the climb is't really going to change things much. you need a much larger change to really affect combat performance/results.

 

[tomo pauk]

Not by much, the same basic supercharger used on the -33 Allison was used on the later ones that got 1150hp at over 15,000ft. A usable set of 9.60 gears (or something in between the 8.77 and 9.60 gears) would have given the 1040 hp a few thousand feet higher (at the cost of power lower down).

It was mostly 1125 HP at 14500-15500 ft, for the 9.60 gears S/C.
The same basic superchager of Merlin I when outfitted with proper intake gave even better power increase on Merlin 20, and it was also a 2-speed S/C, without sacryficing low-alt power.

Adding 100-200fpm to the climb is't really going to change things much. you need a much larger change to really affect combat performance/results.

Time for R-2800-powered fighter, as well as a fighter with more than one stage of supercharging for V-1710 and V-1650, and probably with one powered by the Merlin 20 equivalent.

 

[Shortround6]

All true, but the point is until Hooker puts the better intake on the Merlin supercharger it is being choked by the inlet and the total package doesn't offer much improvement over the Allison. Since very few people knew the difference there is no "AH HA" moment where somebody could point to the Merlin II/III in 1938/39 and say "you know, if we licience this engine and straighten out the supercharger intake we could have real world beater in a couple of years" The Allison supercharger in 1939 was within a few percent of the Merlin supercharger as it existed in 1939.

 

[Kevin J]

All true, but the point is until Hooker puts the better intake on the Merlin supercharger it is being choked by the inlet and the total package doesn't offer much improvement over the Allison. Since very few people knew the difference there is no "AH HA" moment where somebody could point to the Merlin II/III in 1938/39 and say "you know, if we licience this engine and straighten out the supercharger intake we could have real world beater in a couple of years" The Allison supercharger in 1939 was within a few percent of the Merlin supercharger as it existed in 1939.

Packard signed their licensing agreement in September 1940, so as I see it, maybe such an agreement could have been signed in September 1939 for the Merlin X for first deliveries in late 1940.

 

[tomo pauk]

All true, but the point is until Hooker puts the better intake on the Merlin supercharger it is being choked by the inlet and the total package doesn't offer much improvement over the Allison. Since very few people knew the difference there is no "AH HA" moment where somebody could point to the Merlin II/III in 1938/39 and say "you know, if we licience this engine and straighten out the supercharger intake we could have real world beater in a couple of years" The Allison supercharger in 1939 was within a few percent of the Merlin supercharger as it existed in 1939.

People from the USA, namely people from 'Wright Field Engineering Section', certainly knew that Merlin has a far better potential for hi-alt power than V-1710 already in February of 1938, as can be seen at pg. 325 of 'Vee's for victory'.
As a reply to thier report, Allison proposed a better carb as a short-term improvement, and designing a completely redesigned S/C and induction system as a long-term (18-24 months) improvement.

Packard signed their licensing agreement in September 1940, so as I see it, maybe such an agreement could have been signed in September 1939 for the Merlin X for first deliveries in late 1940.

Make a deal with Packard instead with Ford from day one, saves perhaps 3 months vs. historical date (Sept 1940 'down to' June 1940)?