Corsair VS Spitfire

[drgondog]

Thanks to you both. SR - I have a need to publish documented tests forming documented Range parameters for a new book. RCAFson - I need the rest of the report to parse the test runs,..

I am writing a book that may be titled "Mustang - The Bastard Stepchild that saved the 8th AF".

The body of the book will start with Casablanca and POINTBLANK directives and move forward through the growth of the 8th AF into the Crisis of October 14, 1943. In the background will be the frenzy initiated by Arnold, Eaker and Spaatz searching for long range escort solution leading to Arnold to tell Barney Giles "Go fix this and have a solution by December, 1943". The development of Ferry tanks, combat tanks, tank pressurization, internal fuel increase and (briefly) the birth of the P-51B. the introduction of the P-38J and development progress to increase internal fuel - are part of the story. I am not going to devote much time to the politics of Echols/Material Command obstruction re: the P-51 acceptance.

Part of the book will be a technical section highlighting documented performance for P-38, P-47, P-51, Bf 109G-6, FW 190A7 at SL, 5,000 feet, 20,000 feet, 25,000 feet and 30,000 feet (dash and climb) bridging Summer/Fall 1943 through D-Day.

An often asked question is "If the AAF had the F4U-1A (with max internal fuel of all versions) could it have been a major contributor in the 8th AF escort role". The answer is partially yes, to the extent that projected Combat Radius with boundary conditions same as AAF metrics, would permit about the same as the P-47D-25 with 370 gallons but at lower escort altitude and cruise airspeed. What remains unanswered for comparison purposes is the Cruise and Combat performance at 25,000 and 30,000 feet where the P-47D really stood out in comparison.

What is clear (to me, at least) is that from F4U-4 series and beyond, stripping the unprotected wing tanks (361 to 237 gallons) and reducing internal fuel well below the early P-47D 305 gallon, would render the F4U to Penetration and Withdrawal escort role. Still Greater than Spit IX but maybe not as good a performer at 25000+ feet. I suspect without hard facts that the key question would have been "F4U-1 vs P-38H" not F4U-1 vs P-47.

Thanks to you both.

Bill

 

[Peter Gunn]

Not sure these are of any help but the detail specification sheets do have some data regarding endurance for long and short range as well as fuel carried.

For the F4U-1
http://www.wwiiaircraftperformance.org/f4u/f4u-1-02155.pdf

http://www.wwiiaircraftperformance.org/f4u/f4u-1d-detail-specification.pdf "Endurance" around Pg. 6

For the F4U-4

F4U Performance Trials which appears to be a cleaned up HTML version of the two below and does give both an endurance figure and a combat radius number about 2/3rds the way down.

http://www.wwiiaircraftperformance.org/f4u/f4u-4-80765.pdf

http://www.wwiiaircraftperformance.org/f4u/f4u-4-detail-specification.pdf "Endurance" around Pg. 8

I realize you need data similar to what the AAF would have needed for a mission profile and this may not help but hope you'll take it in the spirit it's intended.

And I want a first edition of this book, I can't tell you how much interest there is in that subject for me.

 

[Shortround6]

I have no tests but it seems the F4U-1 might be a bit lacking in high speed cruise.
The British data sheet provided showing 297mph at 20,000ft at max lean cruise.

Unfortunately the endurance figures here.
http://www.wwiiaircraftperformance.org/f4u/f4u-1d-detail-specification.pdf

make no sense. 1.15 hours at max continuous power (rich) 1550hp calls for 250 gallons an hour on the
specific engine flight chart

Impossible on the 237 gallons listed in the detail specification chart. and the lower power cruises don't make sense either.

Even at 60% speed (386mph at 21,500=237mph) and assuming the Corsair can fly at 237mph using about 600hp at 21,500ft that means 53 gallons an hour (best case?) and 4.82 hours means 255 gallons???

I can well understand your need for actual tests as the published charts don't add up unless I am missing something?
Pilots manual is no help as the only range chart shows variations for weight and fuel while giving an altitude of 5500ft. I am assuming the speed is the 150 knots mentioned earlier in the manual for best range at 42 gallons an hour.

 

[fastmongrel]

I can well understand your need for actual tests as the published charts don't add up unless I am missing something?
Pilots manual is no help as the only range chart shows variations for weight and fuel while giving an altitude of 5500ft. I am assuming the speed is the 150 knots mentioned earlier in the manual for best range at 42 gallons an hour.

Cruising at 5,500ft and 150knots over Europe turns you into a dead pilot.

 

[XBe02Drvr]

So the best British warbird VS the (IMO) best American warbird of the war. How do they compare.

F4U-1 series vs the Merlin engined Spits
F4U-4 vs Griffon engined Spits

I go with Corsening: If I'm the government procurement officer, send me Corsairs for their range, ruggedness, and versatility, and I'll make sure the pilots get top-notch training; if I'm the pilot whose ass is on the line and I'm defending my base, give me a Griffon Spit.
Cheers,
Wes

 

[drgondog]

SR - you highlighted the precise reason that I want to see the documented test runs including the cruise speeds and fuel consumption at specific altitudes.

 

[eagledad]

[



Drgondog

Don't know if you can use these to calculate/determine the range of the F4U at 25,000 feet, but I am sending them to you for your inspection. Pages 2 and 3 of the -1, and 4-7 of the 1D contain range data and the mission profile.
Note that the ranges for the -1 are based on a flight test.

Eagledad

 

[mad_max]

Fly both planes to their strong points and both are good for what they were designed to do.

Would you try to dive away from a F4U in a Spit? Would you try turning with a Spit when your in a F4U?

Use performance based on 100% power and not any kind of emergency power. Brief spurts of extreme power doesn't make for a better aircraft.

 

[XBe02Drvr]

Use performance based on 100% power and not any kind of emergency power. Brief spurts of extreme power doesn't make for a better aircraft.

(Spoken like a true groundling!)

NO!, it makes for survivors and an improved kill-to-loss ratio!

 

[Shortround6]

If brief spurts of extreme power didn't make for better aircraft an awful lot of air forces and companies spent an awful lot of time and money on better fuel, water injection systems and nitrous -oxide systems.

I would also note that most engines were only allowed to use 100% power for 5 - 15 minutes. 100% was NOT max continuous or even climb power.

 

[pbehn]

I think most pilots would be looking hard at the fuel gauge if doing significantly more than 15 minutes of 100% power.

 

[Shortround6]

Quite possibly but that was the standard for US escort fighters over Europe. 5 minutes at WER and 15 minutes at military power (100%) for a 20 minute total. The other problem was overheating the engine or running it at higher than "normal" temperatures for more than the rated time.

and just so we are on the same page the Corsair used 275-290 gallons an hour at 100% power (2000-1650hp) depending on altitude and supercharger gear selected and 220-250 gallons an hour for 1675-1550hp depending on altitude and supercharger gear selected so backing off just a little bit didn't do a whole lot. max lean cruise (1070-950hp) used 82-93 gallons an hour depending on altitude and supercharger gear selected so unless the fighter pilot can cruise at Max lean or below he is sucking a lot of fuel.

 

[drgondog]

Fly both planes to their strong points and both are good for what they were designed to do.

Would you try to dive away from a F4U in a Spit? Would you try turning with a Spit when your in a F4U?

Use performance based on 100% power and not any kind of emergency power. Brief spurts of extreme power doesn't make for a better aircraft.

The Placard Limit Dive 1G dive speed for F4U-1 was 3mph higher(443mph IAS) than P-38J/L (440IAS).. if the Spit had any kind of lead it could dive away. The dive Acceleration of the F4U-1D was nearly the same as the P-51D, slightly faster than Spit IX.

 

[Peter Gunn]

The Placard Limit Dive 1G dive speed for F4U-1 was 3mph higher(443mph IAS) than P-38J/L (440IAS).. if the Spit had any kind of lead it could dive away. The dive Acceleration of the F4U-1D was nearly the same as the P-51D, slightly faster than Spit IX.

So with that in mind, the P-51D is able to out dive the F4U-1 then? As I recall (wrongly probably) the 51D was limited to 505mph IAS?

 

[pbehn]

Quite possibly but that was the standard for US escort fighters over Europe. 5 minutes at WER and 15 minutes at military power (100%) for a 20 minute total. The other problem was overheating the engine or running it at higher than "normal" temperatures for more than the rated time.
.

It is easy in the course of a discussion to consider 15 minutes as a short period of time. In terms of motor sport it is a very very long time to have a high performance engine on full power. I presume there was a compromise with power boosting methods. It may be desirable to have longer with water methanol or nitrous injection but it also means carrying more water methanol or nitrous oxide apart from the problems of overheating and engine damage.

 

[GregP]

Nevermind the delays for service use, the F4U flew 29 May 1940. The P-51 flew 26 Oct 1940.

But, the first production F4U-1 reached the Marine Corps on 30 Jul 1942 and was cleared for carriers from Feb 1943. The F4U-4 reached combat in late 1944.

The P-51B/C reached Europe in Dec 1943. The bubble-canopy P-51D reached Europe in the spring of 1944.

Seems fair to compare the P-51D to the F4U-4 and the P-51A to the F4U-1.

Either way, one is a Naval fighter and one is an Air Force fighter, with different mission requirements to fulfill. While I understand comparing the performances, I'm not too sure why one would use one for the mission of the other to start with.

But, you COULD launch P-51Ds from a carrier and recover on land, and you COULD use the Corsair for land-based duties ... if the need were to be extreme. I don't believe anyone at the time thought the need was extreme, and I don't believe anyone actually exchanged the two for one another on actual missions to any extent.

 

[drgondog]

So with that in mind, the P-51D is able to out dive the F4U-1 then? As I recall (wrongly probably) the 51D was limited to 505mph IAS?

P-51B/D could easily out dive the P-38 and F4U-1 and F6F and P-40, it could marginally out dive the F4U-4 and yes placard dive speed was 505 IAS for P-51B/D/H

 

[CORSNING]

Nevermind the delays for service use, the F4U flew 29 May 1940. The P-51 flew 26 Oct 1940.
Seems fair to compare the P-51D to the F4U-4 and the P-51A to the F4U-1.
The P-51D-5 became operational in May 1944 using 67"Hg boosting to the engine as W.E.P. This
boosting level and the low/medium altitude performance of the P-51D were all increased on
10 June 1944 with the advent of 100/150 grade (44-1) fuel. The F4U-4 became operational for the
first time at Okinawa on May 1945. That is one full year after the P-51D made its debut. In war
that is a lifetime of a difference. However, the P-51D was an absolute great aircraft for the roll that
it was cast into. Fair to compare the two? Only because they were in combat at the same time
and the fact that the USAAF did not deme the production of the P-51H as 'top priority urgent'.

Either way, one is a Naval fighter and one is an Air Force fighter, with different mission requirements to fulfill. While I understand comparing the performances, I'm not too sure why one would use one for the mission of the other to start with.
Because of their directives I am going to agree with you all the way on that statement.

But, you COULD launch P-51Ds from a carrier and recover on land, and you COULD use the Corsair for land-based duties ... if the need were to be extreme. I don't believe anyone at the time thought the need was extreme, and I don't believe anyone actually exchanged the two for one another on actual missions to any extent.

Agreed.

 

[tomo pauk]

Nevermind the delays for service use, the F4U flew 29 May 1940. The P-51 flew 26 Oct 1940.

But, the first production F4U-1 reached the Marine Corps on 30 Jul 1942 and was cleared for carriers from Feb 1943. The F4U-4 reached combat in late 1944.

Unless delivered via teleport, the F4U-4 could not reach combat area from Connecticut to, say, Okinawa, before couple of months? 1st F4U-4 was delivered in December 1944.
The XF4U-1 1st flew in 1940, but it needed redesign in order to meet new firepower and protection criteria. The 1st Corsair with 6 HMGs and self sealing tanks was delivered in October 1942, ie. whooping 30 months after the XF4U-1, by what time Mustang units made numerous combat sorties.
USN and USMC pilots very much minded the delays for service use of the Corsair.

The P-51B/C reached Europe in Dec 1943. The bubble-canopy P-51D reached Europe in the spring of 1944.

Seems fair to compare the P-51D to the F4U-4 and the P-51A to the F4U-1.

Comparing 1st delivery dates, the F4U-4 was just 2 months earlier vs. P-51H, and 11 months later than P-51D.
Ergo - F4U-4 vs P-51H.

Either way, one is a Naval fighter and one is an Air Force fighter, with different mission requirements to fulfill. While I understand comparing the performances, I'm not too sure why one would use one for the mission of the other to start with.

But, you COULD launch P-51Ds from a carrier and recover on land, and you COULD use the Corsair for land-based duties ... if the need were to be extreme. I don't believe anyone at the time thought the need was extreme, and I don't believe anyone actually exchanged the two for one another on actual missions to any extent.

Agreed.

 

[parsifal]

Carrier service for the Corsair was cleared in the RN well before the USN. But it was a type the RN had its share of problems with, though the high performance of the type trumped these problems.

In Royal Navy service, because of the limited hangar deck height that existed in their closed hangars, Corsairs had to have their outer wings "clipped" by 8 in (200 mm) to clear the deckhead. The change in span brought about an improved "sink" rate., This reduced the F4U's propensity to "float" in the final stages of landing. Despite the clipped wings and the shorter decks of British carriers, Royal Navy aviators found landing accidents less of a problem than they had been to U.S. Navy aviators, who struggled for many months with the type. This was due mainly to the curved approach the RN used: British units solved the landing visibility problem by approaching the carrier in a medium left-hand turn, which allowed the pilot to keep the carrier's deck in view over the left wing anhedral. Not great, but good enough to keep accident rates tolerable. After many monthgs of resistance within the US forces, this technique was finally adopted by U.S. Navy and Marine fliers for carrier use of the Corsair.

The Royal Navy developed a number of modifications to the Corsair that made carrier landings more practical aboard their carriers. Among these was a bulged canopy, raising the pilot's seat 180 mm and wiring shut the cowl flaps across the top of the engine compartment, diverting the oil and hydraulic fluid around the sides of the fuselage.

The RN Navy initially received 95 "bird-cage" F4U-1s from Vought which were designated Corsair Mk I in Fleet Air Arm service. They were followed by 510 "blown-canopy" F4U-1A/-1Ds, which were designated Corsair Mk II (the final 150 equivalent to the F4U-1D, but not separately designated in British use).

430 Brewster Corsairs (334 F3A-1 and 96 F3A-1D), more than half of Brewster's total production, were delivered to Britain as the Corsair Mk III. 857 Goodyear Corsairs (400 FG-1/-1A and 457 FG-1D) were delivered and designated Corsair Mk IV. The Mk IIs and Mk IVs were the only versions to be used in combat. The earlier versions had insurmountable issues for use aboard carriers that made the type virtually non-operational.

However, the RN cleared the F4U for carrier operations well before the U.S. Navy and showed that the Corsair Mk II could be operated with reasonable success. They did manage to operate the type from small CVE decks, but mostly in the aircraft ferry role.

However the type was not without problems; one was excessive wear of the arrester wires, due both to the weight of the Corsair and the understandable tendency of the pilots to stay well above the stalling speed. A total of 2,012 Corsairs were supplied to the United Kingdom.

FAA units were created and equipped in the US, and then shipped to war theaters aboard CVEs. The first FAA Corsair unit was 1830 sqn, created on the first of June 1943, and soon began training operating from HMS ILLUSTRIOUS. This unit was declared operational for operations aboard from the following November, the first such unit in the world. By the end of the war, 18 FAA squadrons were operating the Corsair. British Corsairs served both in Europe and in the Pacific. The first, and also most important, European operations were the series of attacks in April, July and August 1944 on the DKM TIRPITZ, for which Corsairs from CVs VICTORIOUS and FORMIDABLE providing fighter cover.No aerial opposition was encountered on these raids.

From April 1944, Corsairs from the BPF took part in a several attacks in SE Asia, beginning with Operation Cockpit an attack on Japanese targets at Sabang island, in the NEI