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Hi Shortround, to answer one of your questions, let's see … the 1,425 HP / 1,600 WER engines were used in the P-38H, J, K, L, M, the XP-60A, XP-60B, and XB-38. The 1,150 HP / 1,470 WER engine as used in the P-51 and P-51A. these were all F-series engines.
The G-series were used in the P-82's and XC-114 (Allison engined C-54). The -143 made 1,600 HP for takeoff and 1,700 HP at 21,000 feet.
To comment on another, the Wright R-2600 had a dry weight of over 2,000 pounds. The Allison dry weight was a bit over 1,350 pounds. So, the 1,600 HP from the Wright was dragging a LOT more airplane with more drag around than was the Allison making somewhat less HP with less drag.
I'll take the Allison.
1900hp R-2600 "BB" models have been around for a couple of years, just over 1000 delivered in 1943, 1450hp Military at 15,000ft and 1350hp max continuous at 14,800ft. Weight 2045lbs.
By 1943 the A-20 was a dead end, the A-26 has already flown and first production model delivered in Aug, let alone be on the drawing boards.
It was a dead end as far as further extensive modifications.
Spending thousands of engineering and drafting hours on a "modified" A-20 in 1943
That surely would not be the case with trying to fit a more powerful variant of the R-2600? Was it really so that over 1000 of the 1900 HP R-2600s were delivered in 1943?
The R-2600-14 had a dry weight of over 2,000 pounds
The -13 was a 1700hp "B" version and the 1980lbs is certainly close enough. I don't believe I said anything about engine mounts.and the -13 was 1,980 pounds. The engine mount added maybe 50 pounds as you say,
Yes, they DO have a radiator and associated lines, but the installed weight of an Allison V-1710 is many hundreds of pounds less than the installed weight of an R-2600, and the associated airframes are lighter, too, and less draggy.
Inlines can cruise at 75% power all day long. Radials can't.
Why do you think the B-17 was capable of 300+ mph but cruised at 180 mph? Ditto the hellcat and Bearcat, etc. They typically cruise at low rpm and low power, and accelerate when required for the mission. The inlines cruised over the faster than most comparable radial powered planes. By way of example, the F6F Hellcat could make 375 mph, but cruised at 200 mph. The Curtiss P-40E could only make 360 mph, but cruised at 270 mph. Other inline –to-radial comparison are similar.
The 2-stage Allison was only about 200 pounds heavier than the single-stage unit. I might add that our shop HAS two Allison aux-stage blowers and I know what I'm talking about since I have picked one up and have examined it up close an personally.
considering that any two supposedly identical engines can vary in weight by several percent I am not going to get excited about a weight difference of 20-30lbs on a 1600lb engine.So, I suppose we'll have to agree to disagree on this one. Cheers.
Let's see. The Wright R-2600 used only on the XF6F Hellcat? I think you might have missed a few single engine planes … like the Grumman TBF Avenger (definitely mass produced, wouldn't you say? They built 9,839), Brewster SB2A Buccaneer (771 built … qualifies for mass production, I think), Curtiss SB2C Helldiver (definitely mass produced, wouldn't you say? They built 7,140), and Vultee A-31 Vengeance (definitely mass produced, wouldn't you say? They built 1,931).
Thank you for making my point Shortround!
The conventional wisdom states that single stage V-1710 was a lousy performer above 15-20000 ft, due to numerous reasons. The 2 stage variant was better, but it never played a role in the outcome of the ww2. The main user, P-63, went to VVS, and records about the use are scarce.
So what airframe could put the two stage V-1710 into a good use? The performance* is 1150 HP at 22400 ft (military power), WER dry of some 1450 HP at sea level, WER wet 1800+ HP at sea level. Weight is comparable with single stage Griffon or 2 stage Merlin, but it's longer.
*for the engines available in late 1943/early 1944. Late 1944/early 1945 increases the altitude of mil power to 25000 ft