Groundhog Thread Part Deux - P-39 Fantasy and Fetish - The Never Ending Story (Mods take no responsibility for head against wall injuries sustained) (1 Viewer)

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I'm sure that one day, using this forum as guide, an aviation historian will convincingly write about the P-39 Groundhog.
Went to Google, entered "P-39 Groundhog" and lo and behold:

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:lol:
 
Ive had that experience, I once googled something about Mosquito wing profiles and it linked me to one of my own posts here. Funny and worrying at the same time.

I have had that happen many times. What is worse is when you misspell something, google it with the incorrect spelling, and then find a post you made ten years ago with the bad spelling...
 
Hey GregP,

re: "But, I have never seen a WWII fighter with a max climb rate of less than 2,000 fpm before, and still don't think I have. Most of the less than 2,000 fpm climb rates are at normal power, not rated power."

In this case the 1000 BHP Normal power is the same as Rated power, or the maximum sustained power. This was the Normal setting for most (all?) of the V-1710 types until the -89/-91 series (I think these were the first) in the P-38J&L, where it changed to 1100 BHP. I do not think that any of the other WWII aircraft powered by the V-1710 got Normal ratings higher than 1000 BHP. But the US often used Military for IROC (at least during performance tests) until the 5-15 min time limit was used up, and then throttled back off to Normal.

The F4F-3 and -4 are examples of this. The F4F-3 was originally credited with a respectable ROC in Normal power, but was later reduced considerably, and the F4F-4 entered service with a realistic ROC value due to in-service knowledge. The problem was that in pre-service one-off tests they managed to achieve pretty impressive ROCs, but in service the ROC had to be reduced to less than 2000 ft/min due to engine overheating.

The UK usually used whatever rating they could sustain for 30 min (or more) for Climb power as their equivalent to Normal (for example, 2850 rpm at +9 lbs for ~1120 BHP at SL in the Merlin XX). Later in the war, when engines were improved the UK also started using Military or even WEP for climb rates during tests and sometimes in combat when necessary.

I realize you probably know most of this, but others may not so I put it up as I did.
 
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The Martlet as it was known at the time was the first in service with British forces in UK in August 1940, when the BoB was still being waged.

I think our times are slightly out here, the first Martlets arrived in the UK in August 1940, and went to Scottish Aviation that month prior to service. The Martlet didn't enter FAA service until November 1940 with 802 Sqn, which lost all its aircraft when Glorious was sunk. Ten Martlets were sunk on board a freighter en route to the UK in October 1940. Carry on, chaps...
 

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