WWII Fighter Comparison II Corsair v Mustang.

[Chogy]

The Merlin sounds better (smoother) than the R-2800.

BLASPHEMY!! No engine on earth sounds as unique, as cool, as the big-bore WW2-vintage radial engines. The Merlin snarls; the big Wrights and Pratts sound like 100 Harleys in symphony.

[gunnut]

BLASPHEMY!! No engine on earth sounds as unique, as cool, as the big-bore WW2-vintage radial engines. The Merlin snarls; the big Wrights and Pratts sound like 100 Harleys in symphony.

That's part of the problem. Machines should sound and run smooth. Not sputter and chug.

I heard a P-51 at an air show and the sound of that smooth V12 was unforgettable.

From all the numbers and analysis so far in this thread, it looks like the P-51 was elegance to F4U's brute strength. Sometimes brute force is good. You can always get the job done with enough brute force. However, elegance will improve efficiency.

My favorite WW2 American fighter is the P-38. Now if only the P-38 could be equipped with 2 Merlins instead of the 2 Allisons...

[Stitch]

My favorite WW2 American fighter is the P-38. Now if only the P-38 could be equipped with 2 Merlins instead of the 2 Allisons...

Good choice, g! The P-38 is MY favorite WWII fighter, also!

Intereristingly, Lockheed DID propose installing Packard-built Merlins in the P-38, but the WPB nixed the idea, saying all of the US-built Merlins were required for P-51 production. If you read Warren M. Bodie's book, he's got some evidence that a high-ranking member of the WPB had a financial interest in seeing the Alison division of GM keep cranking out the 1710, so he put the kibosh on the Merlin-powered version. Low-level speed & performance weren't improved any with the Merlin, but high-altitude performance was (though, interestingly, at a slight decrease in range).

[USSWisconsin]

BLASPHEMY!! No engine on earth sounds as unique, as cool, as the big-bore WW2-vintage radial engines. The Merlin snarls; the big Wrights and Pratts sound like 100 Harleys in symphony.

[USSWisconsin]

That's part of the problem. Machines should sound and run smooth. Not sputter and chug.

I heard a P-51 at an air show and the sound of that smooth V12 was unforgettable.

From all the numbers and analysis so far in this thread, it looks like the P-51 was elegance to F4U's brute strength. Sometimes brute force is good. You can always get the job done with enough brute force. However, elegance will improve efficiency.

My favorite WW2 American fighter is the P-38. Now if only the P-38 could be equipped with 2 Merlins instead of the 2 Allisons...

The real bane of the V1710 Allison was that it didn't have the intercooler and second stage blower the Merlin did in the P39, P40, and P51A (the prototype XP-39 did have the turbo, but it was removed for export and never put back).

BUT on the P-38 it had a turbocharger and an intercooler - that made the Allison a great engine - in this trim, the Merlin didn't really have any edge on it. Some of the fastest piston engine experimental fighters and racing planes actually prefered the Allison. Water injection was added on late war turbo intercooled versions and it could match or better the Merlin in this trim.

[Gun Boat]

Yup, P&W and Wright radials were the only engines allowed on carrier based aircraft for this reason. At first the Navy was willing to trade the reduced performance for the relaibility but then the NACA (National Advisory Committee on Aeronautics) hoods were developed and the performance loss was minimized and fully erased by the end of WWII.

Liquid cooled max end of WWII
P-51H 487mph
Spitfire Mk XIV 465mph (RR Griffon 61 powered 2 stage super charger w/ 150 octane fuel and 25lbs boost)

Radial max end of WWII
TA-152 471mph
P-47N 473mph
F4U-4 445mph

The TA-152 was actually powered by a Jumo 213 inline V12. From the D model onwards the 190 utilised this engine.

If the question is which aircraft was a better fighter (as in A2A combat) then in my opinion it has to go to the P-51. The superior ground attack capabilities of the Corsair dont make it a better fighter.

The P-51 had the advantage of being more pilot friendly. Pilots fresh from training had a better chance of quickly getting their heads around a 51 than Corsair.

[clackers]

The love of Lt Col Bill Crump for his Mustang was apparent:

The P51D was the answer to a fighter's dream. A wonderful flying machine, it possessed an excellent view of the world around, was a fantastic gun platform and was designed to combat all enemies at any distance from base. With a well trained pilot aboard, the P51D was a match for any and all piston-engined fighters. When you shove 61 inches of manifold pressure to that Rolls-Royce Merlin, and that enormous four-bladed propeller starts chewing up the atmosphere ahead, you receive an undeniable communique. You are going somewhere aloft, and fast. Then when you start manouevering this creature and become aware of the positively sensual balance of the controls, you just might find yourself humming a love song. Every airman worth his tin wings nurses a sneaking suspicion he is a natural as a fighter pilot, and those of us who were blessed enough to fly the Mustang were certain of it.

[1979]

At 300mph plus in a sustained 3g turn to stall the Mustang would turn inside the Corsair by a wide margin.

at 300 mph and a sustained 3g turn the Mustang has a turn radius of 2143 feet and a full 360 deg circle takes 30.5 seconds. (turn rate 11.8 deg/sec).
at 300 mph and a sustained 5g turn the Mustang has a turn radius of 1244 feet and a full 360 deg circle takes 17.7 seconds. (turn rate 20.3 deg/sec).
In order for a mustang to turn inside a corsair turn it has to :

a) pull more g load than the corsair
b) fly slower than the corsair
c) both.

[Albany Rifles]

I did not go to the start so I am not sure if anyone brought this up already.

You are comparing 2 aircraft which came from 2 totally different requirement specifications and were used for different missions.

The Corsair was a naval fighter which was designed for fleet defense; the Mustang was an interceptor which became a strategic bomber escort. Both excelled in the designed roles and also were used effectively in other roles. The Corsair became an excellent strike fighter, night fighter and interdiction aircraft. The Mustang served as a highly effective high speed recce aircraft and proved a great fighter at all altitudes.

That is my attempt to muddy the waters of debate!

[Chogy]

Correct on the "G" analysis. A boeing 777 at 300 knots and 2G has the exact same turn radius as an F-16 at 300 knots and 2G. What counts is the lift and drag, which varies with shape, wing loading, powerplant, and airfoil. One airplane will have an energy surplus vs. the other.

The P-51 shines from it's very high L/D, but the Corsair is no slouch.

USSWisconsin - your video has opened the door to allow me a blatant "look at me" moment... I posted this once in the Modeler's corner. My shop-built 9-cylinder radial. I was very happy, when it finally ran, to hear the distinct radial engine tones, rather than a typical small-engine chainsaw snarl.

That's part of the problem. Machines should sound and run smooth. Not sputter and chug.

Note how I said "100 Harleys in symphony." Going from 2 to 9 or 18 cylinders removes the sputter and chug, and produces a unique sound that is unmistakeable.

[USSWisconsin]

Thats awesome Chogy! Beautiful machine work!

[Chogy]

Thats awesome Chogy! Beautiful machine work!

Thank you. I couldn't resist. It is a blatant thread-jack, and I shouldn't have done it, but I love radial engines, ever since I saw and heard them as a kid at the Oshkosh air show.

When a young person first looks at WW2 fighters, it is always the sleek liquid-cooled airplanes that attract they eye. The radials don't look as fast or potent. But they deliver the same (or better) power to weight, and have the advantage of a simpler and more rugged construction.

Merlin: power-to-weight ratio of .96 hp/lb
R-2800 CB16/CB3: Weight/HP Ratio (dry) - 1.175/1
R-2800 CB16/CB3: Weight/HP Ratio (wet) - 0.98/1

[1979]

Correct on the "G" analysis. A boeing 777 at 300 knots and 2G has the exact same turn radius as an F-16 at 300 knots and 2G. What counts is the lift and drag, which varies with shape, wing loading, powerplant, and airfoil. One airplane will have an energy surplus vs. the other.

The P-51 shines from it's very high L/D, but the Corsair is no slouch.

14.6 according to app-a2.
Not sure about the corsair,I guess similar to the F6 Hellcat.

[Chogy]

14.6 according to app-a2.
Not sure about the corsair,I guess similar to the F6 Hellcat.

That table is a nice find. It's interesting that the P-51 L/D max is superior even to light general aviation aircraft like a Cessna. But one must also remember that the shape of the L/D curve is telling. L/D max occurs at a particular airspeed at a given weight. Deviate from that airspeed, and the L/D changes. I'm suspecting that the P-51 has a generous curve in that L/D remains high. Draggier aircraft can take a much greater hit in L/D as the airspeed varies. More lift, less drag, equates to greater performance and less energy losses while maneuvering.

The very best sailplanes have an L/D approaching 60, meaning one mile of altitude allows for 60 miles travel in still air. Pretty amazing. A sailplane at 16,000 feet or so can glide for nearly 180 miles.

[1979]

It's interesting that the P-51 L/D max is superior even to light general aviation aircraft like a Cessna. But one must also remember that the shape of the L/D curve is telling. L/D max occurs at a particular airspeed at a given weight. Deviate from that airspeed, and the L/D changes. I'm suspecting that the P-51 has a generous curve in that L/D remains high.

If I'm doing the math right , the mustang enjoys a L/D ratio above 10, between 113 mph and 284 mph. ( at sea level and 9200 lb weight)

The very best sailplanes have an L/D approaching 60, meaning one mile of altitude allows for 60 miles travel in still air. Pretty amazing. A sailplane at 16,000 feet or so can glide for nearly 180 miles.

plus thermals