P-47N Thunderbolt vs. F4U-4 Corsair - Which was superior?

[DAVIDICUS]

Anything mechanical can and will break. The person who sent me these pictures only said that the plane returned after developing an engine problem in flight. I don't think it was from contemporaneous combat damage as the plane is still pregnant with external fuel tank.

 

[Colin1]

Anything mechanical can and will break...

Well, yeah
So how often did R28s throw their oil like that?

 

[Snyperboy]

P-47s were high-speed fighter interceptors that were lethal "Flying Pillboxes" with 8 M-2 Browning .50 cal machine guns. F4U Corsairs were well, like P-51 Cs I guess. They were meant for speeds of over 380 mph, capable of intercepting and destroying enemy planes. But my money's on the P-47, because it is faster, more heavily armed, and was built for high-altitude interception.

 

[vanir]

I like the F4U for preference but it's not a reasoned opinion. In fact I'm quite surprised and concerned about this oil cooler vulnerability, I'm wondering why the oil cooler couldn't have some armour plate under the leading edge of the wing to protect it. But I just like the Corsair because it's funky. I know it's probably a much bigger hassle, but the -4 variant is very high performance, I'd prefer it. Probably take a P-51H over a P-47N in the USAAF if I could get away with it too. But I do think the P-47N is just brilliant and don't think I'd be in something better, just personal preferences.

 

[jugggo]

Well they both do have their ups and downs, but most definetly the F4U-4 in the 1-on-1. That is if the P47 didnt use its speed to run away. The Corsair was known to out turn the P51(which model not sure) up to 30mph slower. Even though the Jug had a great roll rate, I do not think that it would be able to keep up with the HOG in ACM. IMHO

****side note****
What would do better the FW190-D9 or the F4U-4

 

[DAVIDICUS]

A few other tidbits:

The Pilots Flight Operating Instructions for the F4U-4 (October 1944 T.O. No. AN-01-45HB1) warned that there was only enough oil for a maximum of ten seconds of inverted flight. Also, where there was damage to an oil cooler with resulting loss of oil, neither the oil pressure gauge nor the oil temperature gauge would register the change in pressure or temperature until all of the oil was out of the system. (See Manual at page 10) Pilots were warned during combat to check the oil coolers and trailing edges of the wings often for damage that could prove catastrophic.

And another excerpt from Crimson Sky The Air Battle For Korea by John R. Bruning Jr.:

Under the Notes for Chapter 3 on page 215:

#6 Though well armored and generally able to withstand battle damage, the Corsair had an Achilles heel in its oil system. ... After a hit in the oil cooler, the Corsair pilot had only seconds either to bail out or crash-land his plane as the engine overheated and seized. More Corsairs were lost than any other type of Naval aircraft during the first six months of the war as the result, in large measure, of this weakness.

Some anecdotal stuff admittedly of no evidenciary value:

An account from Hal Shook who was a Bolt driver:

In the summer of 1944, we were flying near the Seine River, trying to stop the German Army from crossing over and regrouping on the other side. Crossing points along the river were under constant aerial attack and were heavily defended with anti aircraft guns. Approaching the river, we ran into heavy flak, ugly black puffs of smoke so thick it looked like you could walk on it. We were dodging and changing altitude trying to outguess the gunners, when we saw five barges on the water, 10,000 feet below. They were heavily loaded with enemy equipment and troops.

As I rolled into my dive bomb run, almost straight down, my P47 Thunderbolt shuddered as heavy shrapnel slammed into the propeller and engine. Oil streamed out to cover my windscreen ... Bobbing and Jigging from side to side, and with oil still blowing back. I pulled up and away from the river and the flak. Miraculously, the engine was still running. It carried me to an emergency landing strip in Normandy.


From an interview with Francis Gabreski:

CUNNINGHAM: Your combat experience, Colonel... was there any one action that stands out in your mind, any combat that you particularly remember?

GABRESKI: So he came down, and I broke into him. And as he went on by me, firing, I pulled up in sort of a chandelle. As my airspeed was dropping, he came back up again, turned around, and started coming into me. As he was coming up, I gave him a 90-degree deflection shot. Well, the first deflection shot was great. In other words, he fired and I could see the 20 millimeter gun spittin' smoke, or spittin' fire. I broke and he lost his airspeed, and I went down into him and he came down after me and we picked up enough speed and went . . . I did that twice, and on the third one I had all the confidence now that I was gonna run him out of ammunition.

So the third time we went ahead and did this same thing and he came up with about a 90-degree deflection shot again, the same shot that I'd been giving him. I was very fortunate the first two times, but that last time he rang the bell. I mean, he really hit me!I heard an explosion in the cockpit and I felt my foot grow numb. I lost power in my engine. I says, "Oh, boy!" So the first thought that came to my mind was that the high explosive blew up as it hit my foot. And the second thought that came to my mind was, "oh, he hit my engine, so that's it. I'm out of power and I've gotta go down - bail out - whatever." So I pointed the nose down again, rolled over in kinda a steep dive, pointed the nose down and I was afraid to look at the foot because with the sight of blood, or something like that, I mighta gone into shock and passed out. So I didn't look. I pulled back on the canopy and was ready to bail out. I looked at my airspeed indicator and I still had plenty of airspeed, but my RPM started coming down and my manifold pressure started coming up. So the thought again occurred to me that, "Well, it must be the turbine supercharger and not the engine." And then I looked at the foot and at the pedal. The pedal was shot away but the foot was in good shape. I had heavy boots on and the bottom side of the boot was kinda shredded and broken up. But the foot was in good shape. ... And I soon discovered, after the individuals at that airbase came out and met me on the runway with the engine shut down and so forth . . . they discovered that the oil tank was practically dry.


Account from P-47 Pilot Gildas David McDowell:

On October 14, 1944 we were sent deep into German-held areas of France to locate and destroy any transportation, mainly trains. On my 42nd mission we found a very long freight train sitting out in the open. As standard operating procedure two of us dropped down to check it out for protection. When we strafed at high speed, I saw no sign of protection. In such cases we would then take turns going down to shoot it up at slow speeds.

But as I lined up to start my strafing run I was surprised to see the boxcar doors opening up and the roofs of some boxcars also open. In no time it was clear we had flown into an anti-aircraft trap. I saw many balls of fire coming at me. The first hit was directly into my engine, then one in the right wing. I continued strafing until I passed over them. Then we headed back to friendly territory. Oil and smoke were blowing back over my aircraft. The oil pressure dropped to zero and the cylinder head temp went up to the peg. I climbed to 7,000 feet but could not catch up with the rest. Any time I advanced my power, the engine would vibrate violently. I figured that my prop had been severely damaged.

I landed at the edge of some woods and could see soldiers were running up the hill towards me. I ran into the woods and hid under a brush pile. A few hours later I heard barking dogs approaching so I ran out the far side of the woods. But by this time they had the area surrounded; so I became a prisoner of war.

 

[FLYBOYJ]

Lastly the Pilots Flight Operating Instructions for the F4U-4 (October 1944 T.O. No. AN-01-45HB1) warned that there was only enough oil for a maximum of ten seconds of inverted flight. Also, where there was damage to an oil cooler with resulting loss of oil, neither the oil pressure gauge nor the oil temperature gauge would register the change in pressure or temperature until all of the oil was out of the system. (See Manual at page 10) Pilots were warned during combat to check the oil coolers and trailing edges of the wings often for damage that could prove catastrophic.

Actually that's SOP for a number of round recip aircraft - I didn't go through the whole thread today to see if anythng was posted on the P-47 with the same limitation.

 

[DAVIDICUS]

I didn't know that. I have P-47 manuals for B, C, D, M and N and I do know that there are no warnings about loss of oil pressure and high temperatures from combat damage not being displayed to the pilot.

 

[DAVIDICUS]

More on the general discussion regarding whether the P-47 was a good roller.


August 23, 1943 Memorandum Report on USAAF evaluation of flight characteristics of F4U-1 for the purpose of determining combat and maneuverability characteristics.

3. Combat Characteristics
...
B. F4U-1 vs. P-47C
...
6. The airplanes have the same rate of roll in level flight speed but at 300mph the P-47C is better and remains better as diving speeds increase.

http://www.wwiiaircraftperformance.org/f4u/f4u-1-02296.pdf

 

[renrich]

That information on the roll rate of P47C does not match up with the the steady roll rate graph based on NACA information. The P47C according to it has a peak roll rate of 84 degrees per second, limited by a 50 pound stick force, at about 225 mph IAS, where it begins to drop off steadily.

 

[billswagger]

That data is a bit old pluss we are looking at the P-47N which was definately faster in rate of roll over the D model.

The comparison is close as I've seen climb data that actual puts the F4U and P-47 at near equivalent climb rates up to 30k where the P-47 gains a significant climb advantage of 1000fpm.
The best climb of the P-47N at gross normal weight is 3580ft minute, and the F4U-4 appears to be about the same.

P-47N is faster by about 30mph in level flight.

The F4U trades dive speed for turn, although in a clean configuration (ei no flaps) the P-47D had a better turn rate than the FG-1 airframe. Given the similarity of the later model airframes i don't think that there would be much difference there.

As for turn radius there is no doubt the F4U could make a tighter turn. The P-47N was a heavier plane, and i dont see turn radius getting any better for the P-47 in that regard.

Fire power and payloads, Both very capable and i would say could perform equivelant tasks except for obvious reasons the N had better range.

I think the P-47N is the better fighter only because it could fly higher and faster in combat enviornment where most JPN fighters could out turn and out climb American fighters by a significant margin.

I saw another thread about Ki-84 being better in climb rate than the N model, but i would argue not in the zoom climb which both the F4U and P-47 airframes excelled at.



Bill

 

[renrich]

The P47N is faster in level flight at what altitude? How do they compare at SL, 10K, 20K feet?

 

[davparlr]

The P47N is faster in level flight at what altitude? How do they compare at SL, 10K, 20K feet?

About the best I can get is as follows:

SL
F4U-4 379
P-47N 364

10k
F4U-4 395
P-47N 399

20K
F4U-4 433
P-47N 434

But there is other data

 

[billswagger]

P-47N
http://www.wwiiaircraftperformance.org/p-47/p-47n-republic-wep.jpg


F4U-4
http://www.wwiiaircraftperformance.org/f4u/80765-level.jpg

I was looking at these two graphs, but i saw more information on this site that also showed this:

http://www.wwiiaircraftperformance.org/f4u/f4u-4.pdf

It plots the initial climb rate closer to 4800 ft per minute.

With 150 gal tank and pylons for rockets
S L = 374mph
10,000ft = 420mph
20,000ft = 440mph peak at 22kft 451mph
30,000ft = 420mph

clean config, no pylons, no tanks:
SL: = 383mph
20,500 = 463mph


In light of this, the F4U may have matched the P47N in top speed in clean configuration, however now i have to wonder if the performance of the N would've been similar to the M if it was tested with out pylons.

Needless to say, the F4U may have been the better plane for lower altitude engagements and point interception with a starting RoC of 4800ft/min.



Bill

 

[renrich]

No question that the two aircraft were optimised for different missions. This is somewhat off topic but I always have wondered why the F4U5 did not go with the bubble canopy. The FG?, (don't want to look it up but the AC with the R3350?) had the bubble canopy and looks as if visibility would have been improved.

 

[drgondog]

P-47N
http://www.wwiiaircraftperformance.org/p-47/p-47n-republic-wep.jpg


F4U-4
http://www.wwiiaircraftperformance.org/f4u/80765-level.jpg

I was looking at these two graphs, but i saw more information on this site that also showed this:

http://www.wwiiaircraftperformance.org/f4u/f4u-4.pdf

It plots the initial climb rate closer to 4800 ft per minute.

With 150 gal tank and pylons for rockets
S L = 374mph
10,000ft = 420mph
20,000ft = 440mph peak at 22kft 451mph
30,000ft = 420mph

clean config, no pylons, no tanks:
SL: = 383mph
20,500 = 463mph


In light of this, the F4U may have matched the P47N in top speed in clean configuration, however now i have to wonder if the performance of the N would've been similar to the M if it was tested with out pylons.

Needless to say, the F4U may have been the better plane for lower altitude engagements and point interception with a starting RoC of 4800ft/min.



Bill

Pylons should reduce speed by ~ 10mph but neither the P-47N or the P-51D-H would have a mission in which pylons were removed..

These discussions often dive into flight test data without context and the reporst have to be fully examined to understand loadout for fuel and ammo - as well as fuel type/boost parameters.

One thing that also should be speculated about - what are the likely conditions these ships would have at most likely point of engagement.

For Mustang and P-47N it is at or around target area during penetration through withdrawal...

For F4U and F6F it might be closer to 300 mile radius from carrier.

For Me 109 and Fw 190 and Spit, even closer to point of origin.

Because of nature of drop tanks and mission, both the P-51 and P-47 are likely to have most of their internal fuel remaining when they punch drop tanks for a fight.. The other birds are more likely to have ~ 2/3 internal fuel at radius of contact.

Daveparl has hit this point repeatedly in various comparisons

 

[MikeGazdik]

No question that the two aircraft were optimised for different missions. This is somewhat off topic but I always have wondered why the F4U5 did not go with the bubble canopy. The FG?, (don't want to look it up but the AC with the R3350?) had the bubble canopy and looks as if visibility would have been improved.

FG2 Corsair. Powered by the P&W R4360 though, not the Wright R3350. And I never thought of that, I wonder why they did not use the FG2 airframe after the F4U-4. Seems only logical.

 

[FighterFool]

I don't know if anyone is still following this thread, but if so, I heartily recommend each of you read Robert S. Johnson's excellent biography, "Thunderbolt". As I recall, Bob Johnson was the leading Thunderbolt ace. In his story he reports of "Jugs" returning to base with big pieces of tree branches lodged in their wing leading edges and even bricks in their engine cowlings from inadventant encounters with chimneys during low altitude sweeps over Europe. He also relates his own experience of being shot up over Europe, and, being unable to get the canopy open far enough to bail out, nursing his plane back to England to land at his base. After being freed from his plane he counted over 100 bullet holes and 6-20mm shell holes while standing in one place. Cylinder(s?) had been shot away from the engine, etc. The place was junk, but it brought him home. It's been years since I last read the book, now I think I'll have to find it again!!

 

[renrich]

I have the book and have quoted from it several times as have other members of the forum. The episode where he went home with a jammed canopy and was shot up by an FW with no cannon ammo left has been discussed often.

 

[zpd307]

i have talked with two ww ii veteran pilots that live here in town. actually three, but one was a p-47 pilot, one was a f4u- pilot and one was a b-24 pilot. they were all partial to their own aircraft..... didnt see that one coming, did you?