Wright R-2600 and a US La-5

[muscogeemike]

According to what I've read (and people here know a lot more than me) Curtiss Wright started developing the R-2600 radial engine in 1935. What if someone, and the USAAC and USN, had developed fighters around this engine? I know it was used on several bombers (the A-20, B-25, TBF) and it had problems until late in the war but if enough emphasis was put on the project couldn't the US have had a fighter with about the same capabilities of the La-5 (the R-2600 developed about the same power, 16-1700 hp, as the La-5's engine) at the start of the war?

I know that the La-5 would not have met the strategic requirement of long range bomber escort and the USSR had problems with it for a while; but wouldn't a plane like it have been valuable in the defensive battles at the start of the war? Instead of the P-36, P-39/400, P-40, F2B and F4F; we might have had a much more capable fighter at Pearl Harbor, the Philippines, Northern Australia and over New Guinea and the Solomon Islands.

And if the project were really pushed could we have this fighter (or a version of it) early enough to supply to European countries prior to 1939 or the fall of France? I would think that may have had a lot of influence on the early stages of the war.

 

[davebender]

The U.S. wouldn't build a La-5. It would be more like a small Corsair. About the size and engine power of the original Fw-190A1.

 

[muscogeemike]

I didn't say we would build a La-5. I ask if we could have designed a fighter around the R-2600 - which had the same power as a La-5's engine - and put a maximum effort to it.

If the engine was first tested in 1935 why didn't someone think to use it in a fighter earlier? Could we have had a fighter with similar capabilities to a La-5 and have it in production around 1938?

I would guess it would be more of an up graded P-35 or P-36 or maybe the original F6F which, at first, was going to use the R-2600 - although Grumman didn't start thinking of this until 1940 or 1941.

The R-2800 was first tested in 1938, and the Corsair, the Thunderbolt and others were envisioned to use this power plant - why were no fighters designed to utilize the R2600?

 

[Shortround6]

We have had more than a couple of threads on this topic.

The R-2600 had a couple of strikes against it, some of which were just timing. The first plane to fly with the R-2600 was a Boeing flying boat in 1938. The very early versions were only rated for 1200hp ( the first paper R-2800 was only promising 1650hp)
so it's power to frontal area ratio wasn't very good. 2nd strike was that the supercharger on the early versions wasn't that good and the engine was set up for low level flight. These commercial engines had no military rating. the R-2600-A2 was rated at 1200hp at 2100rpm at 5400ft although 1500hp was allowed at 2300rpm for take off. By 1941 the engine was good for 1700hp for take off at 2500rpm. More importantly it had been fitted with a 2 speed drive for the supercharger, the supercharger may have been improved, the engine had been beefed up ( steel crankcase for one thing) and had been rated on 100 octane fuel. Of course by this time the R-2800 in production at 1850hp with 2000hp models under test.
Knowledge on how to cowl a radial engine was being gained all the time but in 1935-39 large radials had high drag. the R-2600 had the frontal area of an R-3350.

 

[Ivan1GFP]

The original design for the F6F Hellcat DID use the R-2600. Apparently the R-2800 was just a better fit for the size of airplane that US wanted.

- Ivan.

 

[tomo pauk]

After the R-2800, my favorite US engine

As SR6 already stated, there is quite the number of the threads that cover the issue. An R-2600 engined fighter need almost perfect timing in order to present a viable solution. The production should start some time in mid/late 1940 (using the 1600 HP versions), and by the late 1941 the 1700 HP version is available, but almost so is the single stage R-2800 (1850 HP). A design starting with R-2600 has some appeal as a stepping stone for the platform for the R-2800, even if it's a single stage. The R-2600 fighter might be better than a P-40B, of the Flying tigers fame, at least it should climb better?

 

[gjs238]

It seems the following planes successfully used the R-2600.

- Vultee A-31 Vengeance
- B-25 Mitchell
- PBM Mariner
- Martin Baltimore
- TBF Avenger
- A-20 Havoc
- SB2C Helldiver
- Boeing 314

Perhaps R-2600 development was not supported as much as it could have been, in favor of the R-2800.
If true, a good long term decision.
However, an early war R-2600 powered fighter could have provided better performance than the R-1820 R-1830 fighters of the time, albeit not at higher altitudes.

 

[Shortround6]

I am not sure where the "lack of support" for the R-2600 was coming from.

1, Please remember that Wright was working on the R-3350 only a month after they started on the R-2600 but not anywhere near as hard. But the R-2600 was not the most powerful engine in Wrights 'stable'.
2, Depending on which source you believe the R-2600 was using either the first or second supercharger that Wright designed on their own without buying it from General Electric. The Wright superchargers were better than the GE ones but that still leaves a lotof room and NO expertise in the US go to for better designs.
3, The largest aircraft engine plant in the world ( at least in the west) at the time was built with government funds to build the R-2600 (2nd source), Work was started before either Packard of Ford got their contracts aircraft engine plants. 443 engines were delivered in 1941 compared to Packard's 45 Merlins and Ford's 262 R-2800s. First engines rolled out in June of 1941. And this plant had five major sub contractors including Hudson motor cars and Otis elevator.
4, something like 78,725 R-2600s were built by the end of 1944.
5, Wright started work on the R-2160 Tornado in 1940 if not before. How much that siphoned off talent from the R-2600 I have no idea.
6, Wright redesigned the R-2600 twice, Once by switching the crankcase to steel (work on that started in Nov 1938 ) and later by changing the cylinder finning to sheet metal and switching to forged heads instead of cast (?).

While the R-2600 may not have enjoyed the highest priority at Wright for 10 years it certainly seems to have gotten a share of attention ( Wright was still improving the R-1820 too).