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Iirc what the definition of a 'sea level' engine was the Allison could only maintain its rated takeoff power at sea level with the power decreasing as altitude was gained. Thus a 'sea level' engine. An 'altitude engine' was an engine that could maintain its takeoff power to altitude.
Maybe the person who made the statement was talking out his rear end.
In the last paragraph on page 141 the book claims the cost of the Packard V-1650 included a $6,000 royalty payment to Rolls Royce. This is wrong, there were no royalty payments made during the war. Rolls Royce were interested in charging royalties post-war, but Packard ended production.
Boy Tomo, you do ask a lot of questions.
The separate high-atitude boost system for the P-39 was a turbocharger that was ordered removed. It left few choices for Allison other than to change the supercharger gearing and try to make due with what was designed as the low-altitude boost system for the V-1710. That has been covered in earlier posts above.
If I had left out the 8.25 and 10.25 inch impeller, you would have mentioned it, too, wouldn't you?
But I didn't claim any impeller got into combat, so what is your point? I said they were all used and they were. Allisons ran these three impellers during the design's evolution. During early design, it was assumed the turbo would be available, When that proved not to be the case, they had to take as expedient action as they could to compensate for a major engine change that was unexpected. I doubt anybody who had developed their design WITH the turbo could have done much better in as short a time when the turbo was suddenly and unexpectedly taken away. On the other hand, Rolls-Royce DID have Sir Stanley Hooker, though even HE might have a hard time if a turbo was suddenly removed from one of his designs. It might require serious redesign. Don't know, it didn't happen.
The title of the thread doesn't specify WWII, it asks whether the Allison could have done what the Merlin did. Both engines were in use before, during, and after WWII.
The Planes of Fame still uses both today. The G-series engines ran in 1942 but, yes, the P-82 was a post-war product, much as the de Havilland Hornet was, too, even though it used engines that were developed and ran in WWII, too. If you want to confine it to WWII, then the P-82 is surely not included.
The blip switch was the swtich used to set the rpm of the constant-speed propeller. I know the P-40E and N have it but would only be guessing about the rpm control of the rest since I have never asked about it when I am in one of the cockpits. I was making the assumption that rpm control was fairly standardized, but that might be wrong. All have SOME type of rpm control that is easily used if more rpm is desired.
Last point, very much agree. If someone blew up their Allison or Merlin (or radial, or DB, Jumo, or Homare, etc.), they'd likely not tell anbody if they managed to get back home before the war ended. Likey as not it would get reported as an "engine faiure." Honesty has never been one of humankind's top 10 traits, has it?
It would be indeed fine if the pilot returns, after his engine blows up in mid-air, esp. over enemy territory or some big chunk of sea.
Single stage V-1710-81: 1352 lbs dry weight; V-1610-1: 1520 lbs (two speed supercharger, maybe 10% more power at most of the altitudes)
Two stage V-1710-101: 1540 lbs (ADI system adds 50 lbs); V-1650-3/7: 1690 lbs (+ inter-cooler weight - 200 lbs?; more power at high altitudes).
I guess the equivalent of the V-1710-81 would be the single stage, single speed Merlin 45.
Merlin 45 - 1385lb, 1230hp @ 18,000ft.
Merlin 45M - 1585hp @ 3000ft.
I think the typical two stage V-1710 was heavier.
In any case, 50lbs can't give much ADi duration?
The 200lbs you are adding for the V-1650-3/7 is for the radiator and fluid?
Lumsden has 1640lb for Merlin 61/V-1650-3, 1690lb for V-1650-3/Merlin 63, 1645lb for the Merlin 63 and 1645lb for the V-1650-7.
My data is from the document quoted above. Seems Lumsden gives 2 different weights for V-1650-3?
Same for the British built Merlin.AND BOTH engines progressed during the the war. A 1945 Merlin had bits and pieces that were not in a 1940 Merlin or were beefed up/changed and a 1945 Allison had quite a few changes from a 1940 Allison. For the most part you could swap the new pieces in and out or back and forth but you could NOT take a 1940 engine and run 100/150 fuel in it and pull the boost levels that a 1944/45 engine would tolerate. At least not for very long
Wandering through the mists of history, I came upon the above statement.Most Allison installations used a Curtiss Electric prop, and that governor is quite different from a hydraulic governor used to control hydromatic props.