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Shvetsov's M-71 reached 2000hp in 1940 during the factory test according to Kotelnikov, in February 1941 two M-71 were delivered to Polikarpov to be installed on the I-185. The M-71 engine was ready for serial production in 1942.I don't think any of the Italian / Japanese / Soviet / etc efforts had any possibility to reach these power levels in 1941.
The main problem with the M-71 was the long piston stroke. The M-73 with short stroke was quite successful and was quickly brought to serial production. But in 1942, the M-71 successfully passed state tests with a result not much worse than that of other Soviet engines of the same period. The M-81 (direct ancestor of the M-82) reached 1600hp in 1939, and the M-82 reached 1700hp in 1940. The major problem of early M-8Xs was the fuel system - it is just my humble opinion. Shvetsov used a Holey-type carburetor which was extremely unreliable and provided poor mixture quality. The engine required direct fuel injection - taking into account the quality of the soviet aviation fuel.Soviets, already had some engine prototypes in the 2000 HP class at this time, such as M-71. Probably if they start a bit earlier/a bit more focus/less hindrance from the purges they SHOULD get at least a decent 1800 HP radial from one of their designers in 1941
Etc. etc.
The main problem with the M-71 was the long piston stroke. The M-73 with short stroke was quite successful and was quickly brought to serial production. But in 1942, the M-71 successfully passed state tests with a result not much worse than that of other Soviet engines of the same period. The M-81 (direct ancestor of the M-82) reached 1600hp in 1939, and the M-82 reached 1700hp in 1940. The major problem of early M-8Xs was the fuel system - it is just my humble opinion. Shvetsov used a Holey-type carburetor which was extremely unreliable and provided poor mixture quality. The engine required direct fuel injection - taking into account the quality of the soviet aviation fuel.
Actually the japanese COULD get 1800 HP in 1941, Nakajima was working on a 18 cylinder 140x160 engine in 1937, but if they stick with Ha-5 cylinder size 146x160, and focus on it instead of the useless Ha-20 and the failed Mamoru, they SHOULD get 1800 HP out of this 48 litre engine using the same basic cylinder/supercharger design as the Ha-109.
For germans again same recipe, take BMW-132 or Bramo-323 cylinders, join together for an 18 cylinder, reduce the stroke a bit to about 48-49 litres, so you get an 1800-1900 HP engine on B4 with good reliability. Alternatively, have an 18 cylinder based on the 129/329 cylinder size, which works out about 53-54 litre i think, R-3350 size, good for 2000 HP on B4.
I don't think H16 is a particularly interesting configuration. Only a few more cylinders than a V12, bigger frontal area, and weight of two crankshafts.
For H16 and required power, obsolete V12s are certainly out, so are the small V12s (these will serve better in a path towards 24 cyl engine of required power).Pretty much any V-12 is out of the running and the 16 cylinder engines are out too unless they use very fancy engineering.
You need either
Very large cylinders.
Very high RPM.
A LOT of boost (1941 fuel remember)
DB 603A (assumes you can get it into production 1941)
44.5 liters
12 cylinders
2700rpm
2030lbs
over 250hp low (87 octane fuel)
Fairey had the H-24 Monarch engine
But it had some limitations.
51 liters
24 cylinders
3000rpm
2180lbs dry
Width: 43 in
Height: 52.5 in
2240hp
Engine that can give 2000 HP in service, high octane fuel is allowed.We kind of have to figure what a 2000hp engine in 1941 was.
Using high boost settings or WEP settings skews the playing field.
24 cylinder engines means higher cost. We are back the the British not wanting to build the Whirlwind because it used two engines (12 cylinders each) ) but they were perfectly happy to build Typhoons/Tornadoes with one engine (24 cylinders)
Maybe, unfortunately many engine designers of the 1939-41 era seemed be rather in love with their own cleverness. Skipping right on by the Wright R-2160 and looking at the IV-2200 we hit a number of questionable design choices and we hit a few limitationsH24s might've been interesting option for Chrysler (make it instead of the IV-2200)
Have them make a W24 instead?I kind of like this Italian racing plane idea with two V12's mounted behind each other, independently driving counter-rotating props.
But for this thread, it's cheating.
Use it but you have to use the real limitations.I kind of like this Italian racing plane idea with two V12's mounted behind each other, independently driving counter-rotating props.
But for this thread, it's cheating.
Hit a few other problems.Continental was on the right track with their IV-1430, which was on a par with Rolls-Royce's PV-12 early on, but then hit a ceiling with it's weight.