WW2 Without the Merlin: Options for the British

[tomo pauk]

SR6, many thanks again for the great insights. Ditto to aozora.

 

[merlin]

I mentioned this before, but the F5/34 was designed as a long ranged single seat fighter with just 840hp, and a max speed of 316mph. Its almost unfathomable that the RN did not ressurrect this design in 1937 when it finally got control of its own procurement again.
The F5/34 with a Hercules powerplant would have been a formidable carrier fighter. Whilst the hercules was being brought up to speed, it would have been possible to substitute the twin wasp using imported engines until domestic product was developed.
As I said, it defies logic that this pathway was not followed. The RN convinced itself that it needed a multi role fighter recon which was the basis of the Fulmar. I would defend the Fulmar anytime against its detractors, but 1st line material it was not. A Hercules/twin wasp powered f5/34 would have been as good or better than a Zero if it had been developed.

I agree that the Gloster f.5/34 wold be a prime candidate to take the Twin-Wasp - not different in size weight. However, IMHO I'm not at all convinced it could take the Hercules - both longer and heavier, which will shift the CofG!

I think it's a better aircraft for the Far-East than the RN - see my entry in the Poll for Allied Aircraft in the Far East - last entry goes back to May!

 

[Aozora]

The G-R series had the flaw of no center bearing on the crankshaft between the two cylinder rows. Increasing the force acting on the pistons (higher boost and cylinder pressures) is going to result in more crankshaft flex and failed crankshafts or failed bearings or both. The structure of the engine is limit on power with this engine. Please note that the G-R "R" series engine being flown in 1940 DID USE and center bearing but it needed a new crankshaft and crankcase and picked up several hundred pounds in weight.

No centre bearing? I can see why the engine wasn't even flown, let alone accepted because the 1937 article doesn't mention that Alvis added a center bearing. So essentially the Pelides might have been a comparative lightweight and used better engineering and materials than the G-R, but it was still seriously flawed. If Alvis continued the practice with the 18 cylinder Alcides.

Another 1937 Flight article shows how much effort Alvis put into the engines Alvis Engine Testing 1937 Flight Archive

 

[Shortround6]

The same flaw doomed the Armstrong-Siddeley Tiger, the first production engine to use a 2 speed supercharger. Even the earlier and smaller Jaguar and Panther had problems but what you can get away with in 400-600hp 14 cylinder engines is not what you can get away with when you try for 900-1100hp.

I would also note that the 1190lb weight given in some of these tables is for a direct drive engine, Prop turns the same speed as the engine.