F4U-4 vs P-51D

[jedi391]

Here is the scenario, a P-51D and a F4U-4 meet off the California coast on a nice clear day. They are both within range of their home base and have a full tank of fuel. Pilot skill is equal, who do you think wins and why.

 

[davparlr]

The P-51B/D and the F4U-4 may have had similar performance below 10k but certainly above that the F4U-4 had quite an advantage in speed and climb. However the F4U-4 was deployed a good year and half after the P-51B/D. A better comparison would be the F4U-4 vs. P-51H or the F4U-1D w/water to the P-51B/D. In either case, the performace margin switches to the P-51s.

 

[billswagger]

You forgot to mention altitude in your match up.

I would say the F4U is gonna have the advantage in speed, maneuverability and climb under 20k, and above that the gap in speed between the planes would slowly close.

If they both have full tanks, i've repeatedly heard the P-51D was a real monster to handle with a full load.

With that said, i think the F4U could match most if not all maneuvers capable in the P-51D.

I often wondered why the F4U was not used in the escort roll in the ETO given its range and performance capabilities.

Perhaps the P-51D has a better edge at higher altitudes?


Bill

 

[Colin1]

If they both have full tanks, i've repeatedly heard the P-51D was a real monster to handle with a full load

I doubt the P-51 jock would be out and about within earshot of his base with an escort fuel load

 

[Colin1]

Corsair F4U-4 :Name: Mustang P-51B/C
41ft :Wingspan: 37ft
33ft 8in :Length: 32ft 3in
16ft 1in :Height: 13ft 8in

9,205lbs :Empty weight: 6,985lbs
12,420lbs :Take-off weight: 9,800lbs
14,670lbs :Max take-off weight: 11,800lbs

446mph @ 26,200ft :Max speed: 440mph @ 25,000ft
41,500ft :Service ceiling: 42,000ft
3,870ft/min :Initial rate of climb: 3,950ft/min
1,560 miles :Max range: 2,080 miles

Pratt Witney R-2800-18W 1,950hp @ 23,300ft; 2,450hp WEP owerplant: Packard Merlin V-1650-7 1,450hp; 1,695hp WEP
6 x .50cal mg :Armament: 4 x .50cal mg

 

[drgondog]

You forgot to mention altitude in your match up.

I would say the F4U is gonna have the advantage in speed, maneuverability and climb under 20k, and above that the gap in speed between the planes would slowly close.

If they both have full tanks, i've repeatedly heard the P-51D was a real monster to handle with a full load.

With that said, i think the F4U could match most if not all maneuvers capable in the P-51D.

I often wondered why the F4U was not used in the escort roll in the ETO given its range and performance capabilities.

Perhaps the P-51D has a better edge at higher altitudes?


Bill

If the implication of 'within range of base' is immediately after rotating and climbing out, the 51 will be marginally stable with an aft cg due to the 85 gallon fuel tank. If at a medium rangs - say 100 miles, the 51B will have burned off all or most of the 85 gallons and be down to the 192 gallon wing tank plus the 'external/droppable'.

So, a couple of questions and a statement: The P-51B dash speed from flight test is at that altitude after taking off with full load of internal fuel and climbing to the critical altitude then pouring the coals to the engine at max boost. So the 51B has burned maybe 10-15 gallons and now has 255-260 gallons of internal fuel.

Question - are you specifying the 1650-3 or 1650-7 Merlins, at 67" with 130 or 72" w/150 Octane. That makes a significant difference in several altitude profiles as well as initial climb rate.

Question - what gasoline octane and boost are you thinking about for the F4U-4 in June 1944? The 51B would have that capability (150 octane and 72-75" boost) in June 1944.

Question, what load out, internal and external, are you suggesting for the F4U-4 and what reference do you want to point to that specifies gross weight and engine performance and dates for the F4U-4 to make sure you have apples to oranges.

These two airplanes are so closely matched that these factors are important to nail 'potential' combat performance based on altitude and the location of the fight (i.e. how much internal fuel has been burned)

And, I agree with Dave that the P-51H is a better comparison date wise for the F4U-4 and the F4uD-1 for the P-51B.

My opinion - jump ball based on altitude, starting position of the fight, who sees whom first, which one is looking and which one is thinking about getting laid, etc.

 

[davparlr]

You forgot to mention altitude in your match up.

I would say the F4U is gonna have the advantage in speed, maneuverability and climb under 20k, and above that the gap in speed between the planes would slowly close.

Actually the F4U-4 has very good high altitude performance and will outperform the P-51B/D in speed and climb from 15k to ceiling. The difference is not overpowering, however. Below 10k, the P-51D and certainly the "B" is faster and has roughly equivalent climb as the F4U-4.

[If they both have full tanks, i've repeatedly heard the P-51D was a real monster to handle with a full load.

Comparing aircraft at max weight is, in my opinion, distorting actual performance. It would be very dangerous for the P-51 to dogfight with the "extended range'" tank full and would not have been done by an experienced pilot. My comparisons are at identified "fighter weight".

I often wondered why the F4U was not used in the escort roll in the ETO given its range and performance capabilities.

The F4U-1 had the range to perform the escort job but performance at bomber altitudes was typically below the level of the German opposition, certainly below the Fw-190 although similar to the Bf-109. The F4U-1D w/water did improve performance at those altitudes but did not have the overpowering advantage the P-51B/D had nor did it have the range required (wing tanks were removed). The F4U-4 had the performance needed at those altitudes but, again did not have the range required. Also, it was not available until the war in Europe was basically over.

The F4U-1 would have been better than nothing, although it loss rate would have been pretty high, and it probably would have been more reliable than the P-38.

 

[billswagger]

i was sticking to the P-51D comparison, although the H model is probably the better comparison.

In a recent comparison of the F4U-4 to the P-47N, it was discovered the max climb of the F4U-4 met 4800ft/min up to 10k ft.

Also in a clean configuration, ie no rocket pylons or external tanks, the F4U-4 reached a top speed closer to 460mph at about 22,000ft.

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


Bill

 

[davparlr]

In a recent comparison of the F4U-4 to the P-47N, it was discovered the max climb of the F4U-4 met 4800ft/min up to 10k ft.

Data on the climb rate of the F4U-4 varies with the source. The one you quote does not match other flight test data or Dean's America's Hundred Thousand. Looking at other flight test data and correcting for horsepower variables, I calculated the climb at SL of the F4U-4 at about 4430 ft/min which is also about the number Vought arrived at (4380 ft/min at 12400 lbs). Dean had less, but I think it is in error, possibly listing Mil power performance as Combat power. I think the 4800 number is high.

Ironically, 4430 ft/min at SL is also the flight test results for the P-51B at fighter weight.

 

[renrich]

According to Dean, "America's Hundred Thousand," the F4U4 was the fastest US fighter that served in WW2 at sea level. I believe the high altitude performance of the F4U1 would have been superior to the FW190 but not the ME109 in 1943. The F4U1 with the internal wing tanks during 1943 would IMO, have been significantly better overall at long range escort than the P47 of that time period. In a mock dogfight between contemporaneous Mustang and Corsairs, the outcome would be just as Bill says, dependent on pilot skill, pilot awareness, perhaps altitude and maybe luck.

 

[bobbysocks]

its all going to depend on who can sucker the other one into his kind of fight....

heres a link all about aircraft performance...allied, axis, etc

WWII Aircraft Performance

there is a cool link at the bottom of the page of P 51 encounter reports ( combat reports..from ww2 )

 

[davparlr]

According to Dean, "America's Hundred Thousand," the F4U4 was the fastest US fighter that served in WW2 at sea level.

While I am a huge fan of his book, I am more leery of his performance data. I am sure it was limited by the massive effort to research all available performance data. For instance, for the P-51D, he identifies Combat Power as 67" Hg and it appears for the performance charts that this is the power used. Beginning in May, 1944, the P-51B and D were authorized operation at 75" Hg, a significant increase in power. The AAF, in testing 44-1 fuel, recorded a P-51B, without racks, was capable of 386 mph, 380 mph with racks, all at SL.

I believe the high altitude performance of the F4U1 would have been superior to the FW190 but not the ME109 in 1943.

I have some German data that shows pretty similar performance for the Fw-190A-5 at 20-25k ft.

The F4U1 with the internal wing tanks during 1943 would IMO, have been significantly better overall at long range escort than the P47 of that time period.

Certainly. Up through about May, 1944, when the P-47D-25 came along, the P-47 did not have the internal range to be an effective long range escort, whereas the F4U-1 did. The one advantage the P-47 had in escorting was good performance above 25k. This gave them the high ground. Below 25k, it was at a disadvantage to the F4U and Germans.

In a mock dogfight between contemporaneous Mustang and Corsairs, the outcome would be just as Bill says, dependent on pilot skill, pilot awareness, perhaps altitude and maybe luck.

I agree with this, but I must point out that at any specific timeline after the advent of the P-51B, the P-51 pilot will have an advantage in airspeed and climb from SL to ceiling, except at a few discrete points, over its contemporary F4U. This is comparing the P-51B with the -3 and pre 44-1 fuel -7 engine to the F4U-1, the post May '44 (44-1 fuel), P-51B/D to the F4U-1D(W), and the P-51H to the F4U-4.

 

[baldpuki]

First post but I couldn't help myself. My father was a Mustang driver in WWII and an ace at that. If you google Alden Rigby, it has lots of stuff. After the war, he was stationed at a naval base in Kansas and had access to all the Navy birds. I asked him which plane was better in a fight between the Corsair and his Mustang (D model). He said it was too close to call but he would prefer his Mustang because he was more familiar with it. He really loved the Corsair, though and enjoyed flying it quite a bit. He really like the Bearcat also and said that he didn't fly it...IT flew him!

 

[renrich]

Dav, upon looking at the performance figures for the FW190A5, it appears that the critical altitude for that model was around 20000 feet where it's Vmax and climb started dropping off significantly. The 109G looks like it's critical altitude might have been a couple of thousand feet higher but it was only able to reach around 386 mph at it's critical altitude so I believe you are correct. The F4U1a had a critical altitude of close to 25000 feet so it would have probably been able to cope well with both German fighters in an escort role. Above 25000 feet the P47 would have come into it's own but the F4U1As would have been able to escort at least a hundred miles further.

 

[davparlr]

First post but I couldn't help myself. My father was a Mustang driver in WWII and an ace at that. If you google Alden Rigby, it has lots of stuff. After the war, he was stationed at a naval base in Kansas and had access to all the Navy birds. I asked him which plane was better in a fight between the Corsair and his Mustang (D model). He said it was too close to call but he would prefer his Mustang because he was more familiar with it. He really loved the Corsair, though and enjoyed flying it quite a bit. He really like the Bearcat also and said that he didn't fly it...IT flew him!

Welcome aboard! Great story about your dad, I think he was included in the Dogfight TV show about that battle. I am sure there will be a lot of questions to you about your dad. How is he doing?

The three planes you mentioned were certainly thouroughbreds. It would be amazing to fly one, not to mention all three.

 

[baldpuki]

Thanks for the kind words. Yes, dad was in the Death of the Luftwaffe series. He said it was pretty accurate. There have been a lot of magazine and newspaper articles about him. He is probably America's last ace in that he was officially recognized by the American Ace's Association for the last 2 planes he shot down. He is doing well. He is 87 and is going to help me put some brakes on his car tomorrow. I hope to do as well at his age. Any questions are welcome. We need to never forget these great patriots.

 

[renrich]

It is good to hear about a WW2 vet alive and doing well. Congratulations on your father. All of my uncles (6) who served in that war have now passed away. I regret a great deal not making a record of some of the conversations I had with them about their experiences and also not having more conversations. I hope you are taking advantage of your father's good health, if it is comfortable for him, to record as much of his remembrances as possible.

Dav, as far as performance figures of WW2 AC is concerned, I read on the Williams site that an F4U1 was clocked at 431 MPH at critical altiude which is much better than is in Dean's book and almost up to the level of F4U4 performance. Boone Guyton's book says that the F4U1 had a vmax of 417 mph at 19900 feet whereas Dean has the critical altitude of the F4U1 at about 23000 feet with a vmax at military power of around 395 mph. Dean shows the F4U1A with WEP at military power to have a critical altitude of around 24000 feet with a vmax of around 417 mph and the F4U1A and 1D to have a critical altitude at combat power of only about 19000 feet but with a Vmax of almost 420 mph. I guess where I am going with this is that a lot of performance figures are available for all WW2 AC and some of them may be from specialy prepared AC. In addition, often times manufacturer numbers are different from AAF or USN numbers. Incidently, in reviewing Guyton's book, the F4U5 was finally equipped with automatic blower operation which I had forgotten.

 

[renrich]

Some other performance numbers rediscovered from Guyton's book: "After several engine "run in" flights we began a series of engine cooling and carburetor tests, finally inching up to water-injection speed runs at an incredible 75 inches MP. I approached this awesome power with due apprehension and vivid remembrence. The violence of those overheated, disintergrating engines, the crashes, and the long hospital days were stark reminders of an earlier unpleasantness."

"The trepidation was unwarranted. The new engine ran with satisfying smoothness at all power conditions-cause for celebration. Along with the second F4U4X, # 50301, which was soon ready for tests, performance data were obtained which exceeded estimates. Top speed was now 450 mph at 26200 feet, versus the F4U1D's 425 mph at 20000 feet. Rate of climb was extended to nearly 4000 feet per minute from 3100 feet per minute. Important was the F4U4's service ceiling of 41500 feet-an astonishing increase of nearly 5000 feet."

 

[tomo pauk]

There is really something about the R-2800
Now, how about P-51 with those useful 2000 HP in early 1943...750 km/h perhaps?

 

[davparlr]

Dav, upon looking at the performance figures for the FW190A5, it appears that the critical altitude for that model was around 20000 feet where it's Vmax and climb started dropping off significantly.

After another look at my data on the Fw-190, I agree with you, however the performance of the F4U-1 and early (pre-water) F4U-1A would be very close as both drop off performance pretty quickly above 25,000 ft.

Dav, as far as performance figures of WW2 AC is concerned, I read on the Williams site that an F4U1 was clocked at 431 MPH at critical altiude which is much better than is in Dean's book and almost up to the level of F4U4 performance.

I believe this airspeed is a calculation based on the use of water injection, which was not available beyond test samples until the 1D became operational in the first half of '44.

Boone Guyton's book says that the F4U1 had a vmax of 417 mph at 19900 feet whereas Dean has the critical altitude of the F4U1 at about 23000 feet with a vmax at military power of around 395 mph. Dean shows the F4U1A with WEP at military power to have a critical altitude of around 24000 feet with a vmax of around 417 mph and the F4U1A and 1D to have a critical altitude at combat power of only about 19000 feet but with a Vmax of almost 420 mph. I guess where I am going with this is that a lot of performance figures are available for all WW2 AC and some of them may be from specialy prepared AC. In addition, often times manufacturer numbers are different from AAF or USN numbers. Incidently, in reviewing Guyton's book, the F4U5 was finally equipped with automatic blower operation which I had forgotten.

I have never seen such variables in performance in one airplane. Researching F4U performance gives me a head ache.

I think the top end of non-water F4U-1s, was about 417 mph. For water F4Us a top speed of about 422 to 425 mph is reasonable.

One of the problems with the test data is that they often do not refer to the aircraft version beyond the -1. A person has to read the document to see if it is a pre-1944 F4U-1 or a later water-injected plane, -1A or -1D.

The referenced document seems to be pretty good for water injection F4Us, but, who knows.

http://www.wwiiaircraftperformance.org/f4u/f4u-1-50030-final.pdf