F4U Corsair vs P-51 Mustang

davparir and eagledad,
Thank you both for your input. I greatly appriciate any information that helps me to put together an operational fighter timeline. I'll add this information to what I have on my research desk when I get home tonight. If I can verify that the F4U-1a was operational with water injection early in '44, I'll match it with the P-51B-1. The next matchups after that would be the P-51D / F4U-1D.......P-51B-15 / F4U-4........? / ?

Jeff

I have looked through my copy of AHT and have found the passage confirming water injection in Nov of 1943. I am at a loss finding where it says only 8 F4U-1a's had water injection. Would you please help me find that.

Same page (518), right column dated Jan '44. I don't know why the happy face on the eight. That's page five-one-eight.


Thanks davparir and Corsning for the info.

Your are quite welcome sir.

Jeff.

AHT states: Jan '44-Eight F4U-1As of VF-17 Squadron are being re-fitted with water injection equipped engines.

I did some digging into the history of VF-17 Jolly Rodgers and found that they were doing their first tour of duty in the Solomon Islands on November 8, 1943 and they finished their combat tour with Corsairs on May 10, 1944. They then were equipped with F6F-5s aboard the USS Hornet.

With that bit of information, Matchup No.3 is on.

Corsning,

Thanks!

Eagledad

...P-51B-1 (actually Mustang III) F.X. 953 and (FG-1A, 14575 tested 3/3/44-10/9/44. The test did not include a full altitude test of maximum speed at combat power so speeds are supplied from the Bureau of Aeronautics, Navy Department for an F4U-1 with water injection and in clean configuration.)

Altitude...Speed/Climb
Meters....mph/fpm
S.L......361/3490 (359/3450)
1,000...374/3525 (371/3410)
2,000...387/3570 (382/3370)
3,000...401/3600 (394/3325)
4,000...415/3290 (406/2870)
5,000...424/2865 (411/2655)
6,000...421/2690 (416/2250)
7,000...431/2680 (409/1835)
8,000...444/2300 (400/1300)
9.000...448/1870 (NG./ 935)
10,000.441/1400 (NG./ 570)
11,000.429/1000 (NG./ 205)

Maximums: 450 mph./28,000 ft. and 3,610 fpm./10,600 ft. (417 mph./19,900 ft. and 3,450 fpm./S.L.)

Ceilings
Combat: 36,000 (28,940) ft.
Operational: 39,765 (33,410) ft.
Service: 42,740 (37,000) ft.

Engines: Packard V-1650-3, 1,618 hp.@ 66.8"Hg boost.(Nash Kelvinator R-2800-8W, 2,250 hp.W 60"Hg boost.)

Test Weight: 8,740 lbs. for the speed trials and 9,200 lbs. for the climb trials (12,057 lbs.)

Wing Loading: 37.51+/39.48+(38.40-) lbs./sq.ft.

Power Loading: 5.402-/5.686+(5.359-) lbs./hp.

Armament: 2 x 0.5in./350 rpg. + 2 x 0.5in./280 rpg. ( 6 x 0.5in./400 rpg.)

Roll Rates: FG-1A figures are from 14575 test document and P-51B-1 figures are from the NACA chart which can also be viewed on Mike Williams' sight.

Speed........................150..........175........200........225...........250..........275..........300......mph.
P-51B-1.......................50............61..........71.........81.............88...........93.............96.5....degree/second
FG-1A.Left/Right.....75/75.....78/85....84/88....88/87......90/.......87.2/...degree/second

Matchup No.4: P-51D-15, 44-15342 report dated 6/15/45 and F4U-1D as standardized by the Bureau of Aeronautics in their August 1, 1945 Airplane Characteristics Performance report.

These particular models were improved in several ways over the previous models that they followed. Their performance numbered were slightly lower due to the increased weight the improvements brought

The Mustang was tested with wing pylons in place. I have been told that these were of a more efficient design and of less air resistance, causing 4-6 mph. loss of speed. The F4U-1D was in the absolute clean mode. No shackles, pylons or wing bracing.

Matchup No.4: P-51D and (F4U-1D)

Altitude.Speed/Climb
Meters..mph/fpm
S.L.......375/3600 (366/3370)
1,000...388/3600 (367/3000)
2,000...403/3385 (378/2960)
3,000...416/2985 (391/2930)
4,000...413/2535 (402/2810)
5,000...410/3200 (408/2560)
6,000...420/3100 (417/2280)
7,000...432/2645 (410/1930)
8,000...441/2200 (402/1560)
9,000...431/1765 (392/1210)
10,000..417/1285 (NG./ 860)

Maximums: 442 mph./26,000 ft. and 3,600 fpm./S.L. (417 mph./20,000 ft. and 3,370 fpm./S.L.)

Ceilings
Combat: 35,000 (31,500) ft.
Operational: 38,700 (36,100) ft.
Service: 41,600 (40,000) ft.

Engine: Packard V-1650-7, 1,780 hp./S.L.@ 67"Hg boost. (Pratt Whitney R-2800-8W, 2,250 hp./S.L.@ 60"Hg boost.) Maximum output.

Test Weight: 9,760 (12,175) lbs.

Wing Loading: 41.40-(38.77+) lbs./sq.ft. at take-off. (The weight of an aircraft begins to decline from the moment the engine is started and fuel is being used. Therefor this number continues to decline as long as the engine is on.)

Power Loading: 5.483+(5.411+) lbs./hp. at take-off. (See the above information. + This number is constantly changing do to engine boosting and engine capability at altitude.)

NOTE: By June 1944 72-75"Hg boosting of the V-1650 was approved and in use. The P-51D was just coming into operation around this time. The F4U-1D was also going into operational service around May 4, 1944.

Jeff

These models of each were the best of the breed numbers performance wise. The P-51B-15 came on the sceen in early-mid 1944 and the F4U-4 was introduced to combat in May 1945. (I know the P-51H would be a closer match time wise but it did not make WW2 combat. So, that matchup falls into a different category.)

The P-51B-15, 43-24777 was tested 3/20/44-5/15/44. The information for the F4U-4 is from the Bureau of Aeronautics report summery March 1, 1946.

Matchup No.5: P-51B-15 and (F4U-4)

Altitude...Speed/Climb
Meters....mph/fpm
S.L......388/4330 (389/3870)
1,000...404/4220 (389/3500)
2,000...418/3870 (396/3455)
3,000...420/3840 (408/3410)
4,000...420/3770 (420/3365)
5,000...430/3590 (432/3320)
6,000...441/3100 (445/2915)
7,000...442/2620 (445/2840)
8,000...436/2125 (454/2380)
9,000...NG./1675 (435/1870)
10,000..NG./1200 (416/1350)
11,000..NG./ 715 (397/ 860)

Maximums: 444 mph./20,600 ft. and 4,380 fpm./S.L. (455 mph./26,300 ft. and 3,870 fpm./S.L.)

Ceilings
Combat: 34,200 (35,000) ft.
Operational:37,500 (38,900) ft.
Service: 40,500 (41,500) ft.

Engine: Packard V-1650-7, 1,910 hp.@ 75"hg boost. (Pratt Whitney R-2800-18W, 2,450 hp.)

Test Weights: 9,335 lbs. speed trials and 9,680 lbs. climb trials (12,420 lbs.)

Wing Loading: 40.06+(39,55+) lbs./sq.ft.

Power Loading: 4.885-(5.069+) lbs./hp.

Jeff.

Love your posts, Jeff.
You can look at speed penalties for the Merlin Mustang here, under 'Remarks' column. It is 12 mph for P-51B/C (ditto for the P-51A) and 4 mph for the P-51D/K.
The sped penalty for the F4U-4 with two capped racks can be seen here (pdf; F4U-4 SAC ); 9 kts or 10 mph of difference at altitude between 'combat condition' (two capped racks) and 'clean condition' (no racks). Un-capped racks cut speed for further 8 mph for the F4U-4. The F4U-1D also carrier 2 racks, a more knowledgeable person could tell us whether those were of same construction.

Thank you tomo, that is kind of you.

I thank all the rest of you who joined in with some great information and great stories.

Jeff.

Jeff - the P-51B-15NA came into operational ETO squadrons in Late April, 1944.

I've always thought it peculiar that many folks don't want to compare a favorite fighter that served in 1945 with the P-51H.

The H was always available to deploy in April 1945 but the AAF recognized that post WWII was going to be grim on budgets and they wished to conserve the P-51H for strategic escort, along with the P-47N and saw no reason to deploy them..

It simply doesn't make sense to compare a 1945 version of the Corsair to a 12 month older Mustang version?

drgondog said:

Jeff - the P-51B-15NA came into operational ETO squadrons in Late April, 1944.

Thank you for that date sir.

I've always thought it peculiar that many folks don't want to compare a favorite fighter that served in 1945 with the P-51H.

[B]It is the operational during WW2 thing I suppose.[B]

The H was always available to deploy in April 1945 but the AAF recognized that post WWII was going to be grim on budgets and they wished to conserve the P-51H for strategic escort, along with the P-47N and saw no reason to deploy them..

That decision was a shame for us enthusiast.

It simply doesn't make sense to compare a 1945 version of the Corsair to a 12 month older Mustang version?

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I more or less completely agree. The P-15B-15 under those circumstances did exceptionally well, don't you think.?......................OK now you got me going. Tomorrow I will put together a P-51H and F4U-4 @ 70"Hg boost with 115/145 fuel.

Thank you for the push.

Goodnight all, Jeff

P-51H performance is taken from STANDARD AIRCRAFT CHARACTERISTICS, AIR MATERIEL COMMAND, U.S. AIR FORCE form dated March 22, 1949. The figures on this sheet match the later issued sheet dated July 3, 1950. I took the figures from the Interceptor mode column put them on a graph. I then used the performance lines on a few actual flight test graphs of the P-51H at 90"Hg boost. I matched the lines up at to the numbers given on the chart. I am aware that the P-51H hit 482 mph. on a N.A.A. graph. That was at a weight of 7,302 lbs. with only 4 x 0.5in. guns with 250 rpg. each. In other words, a very stripped down model and not an all-up weight interceptor mode fighter.

F4U-4 performance is taken from STANDARD AIRCRAFT CHARACTERISTICS, BUREAU OF AERONAUTICTS, NAVY DEPARTMENT. I have been told that the figures on these sheet are calculated figures of what the Navy was expecting of the -4 model at 70"Hg. As Neil pointed out in more than one other thread, the R-2800-42W was cleared for 70"Hg, but that setting was never officially used by the USN.

HOWEVER, I have decided to use the above examples for two reasons:
1. These two would only have been in large scale service at the end of WW2 if things were not going the Allies way in 1945.
2. If things were not going our way, it is quite likely that more pressure would have been on both manufactures to increase the performance of their aircraft.

Matchup No.6: P-51H @ 90"Hg boost and (F4U-4 @ 70"Hg boost.(actual performance figures at 60"Hg are used where they exceeded the early calculations.))

Altitude...Speed/Climb
Meters....mph/fpm
S.L......412/5480 (389/4770)
1,000...425/5540 (397/4790)
2,000...438/5165 (411/4805)
3,000...447/4675 (424/4825)
4,000...444/4405 (439/4290)
5,000...447/4380 (445/4340)
6,000...460/4115 (458/3880)
7,000...471/3550 (463/3300)
8,000...465/2970 (454/2650)
9,000...456/2425 (442/2125)
10,000.440/1860 (430/1550)
11,000..NG./1295 (417/ 950)
12,000..NG./ 730 (377/ 450)

Maximums: 473 mph./22,700 ft. and 5,555 fpm./3,960 ft. (464 mph./20,600 ft. and 4,825 fpm./10,250 ft.)

Ceilings
Combat: 37,790 (35,800) ft.
Operational: 40,700 (38,660) ft.
Service: 43,100 (41,600) ft.

Combat Weight (Clean interceptor no shackles, pylons or bracing): 8,740 (12,435) lbs.

Wing Loading: 37.03+(39.60+) lbs./sq.ft.

Power Loading: 3.937-(4.405+) lbs./sq.ft.

Note: The P-51H could out turn and out roll a P-51D. F4U-4 maximum roll rate: 112 degrees/second.

Happy Easter, Jeff

That is a good question.While the Mustang is my favorite the corsairs can do more things, however we don't really know what would happen if f4us dogfight against a German plane.

A corsair can escort a bomber and some squadrons were better at it than Mustangs like VF 17, they did not let ANY Japanese destroy bombers or ships they were guarding.

Blitzrockie said:

A corsair can escort a bomber and some squadrons were better at it than Mustangs like VF 17, they did not let ANY Japanese destroy bombers or ships they were guarding.

Click to expand...

Source?

In a book about VF 17 called skull and crossbones squadron.Its a real account of what they did

Not totally buying into that one at present.

Things that make you go hmmm...

Blitzrockie said:

In a book about VF 17 called skull and crossbones squadron.Its a real account of what they did

Click to expand...

Blitzrockie,

I think they are looking for a bit more data, say Units, dates, types involved. Also if an example is particularly difficult to swallow then copies of pages seem to do well. Go through some of these posts in here and you will get a feel for what people do to validate info.

Cheers,
Biff

davparlr said:

Above 25k ft, the F4U-1 performance drops dramatically. I think that while the Bf-109 may be slightly slower at these altitudes, its superior rate of climb, and probably maneuverability, was sufficient to neutralize any advantage the F4U-1 would have. I am sure some of our German experts could make a more intelligent argument.




A high altitude supercharger was developed, but was not available until mid '44, and was installed in the dash 4. As for a turbo supercharger, the tight cowl and slender fuselage would make an installation dicey (compare with the large fuselage of the P-47).



The F4U was not cleanest of aircraft. It was slightly cleaner than the P-47, however. I have created a variable to compare the aerodynamic efficiency of aircraft at sea level. This is system efficiency since some aircraft generate thrust from their radiators and some from the exhaust. Here are some comparisons. These numbers are mph/hp at SL.

P-51B (-7 engine) .24
P-51D .23
Spitfire Mk XIV .22
Fw-190D-9 .22
Fw-190A-5 .21
Ta-152H-1 .18
F4U-1 .162
P-47D-25 .156
F4U-4 .153
P-38J .13

See above regarding engines for higher altitudes.

A lighter, land based, F4U-1 would have improved climb however speed would probably not have been impacted by more than a couple of miles per hour. If you could give me an estimated weight savings for the land based versions, I could estimate impact to airspeed and climb.

It should be noted that in the Fighter Conference, the P-51 was selected as the second best fighter above 25k, behind the P-47, and second the below 25k, behind the F8F, in both cases ahead of the F4U-1, greatly ahead above 25k, only slightly ahead below 25k (insignificantly so). I believe this is one of the indications of how great the P-51 design was. While not overpowering at all altitudes (it definitely was above 25k until the latter part of '44), it was very formidable from 35k to SL.





In the Soccer War, I believe Soto (?)was a pretty good stick. Also, he was flying an F4U-4 against P-51Ds, not the more equivalent P-51H. However, I agree with your final selection and would hope engine development could get me that -18W engine a lot earlier. And if they could just have squeezed that -57 engine in …….

Click to expand...

It would be interesting to know how the P-51 ended being pick BEHIND the P-47 above 25K feet...other than diving, what could the P-47 possibly have been better at than the 51...it certainly isn't going to outclimb, outturn, or outroll a Mustang...

drgondog said:

Marshall with respect that is a fluff piece. He should aslo compare against the P-51B-15 or P-51H if he wants to make a convincing case

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There was no Corsair model I know of that would been able to compete against the P-51H...