OT: F4U Corsair

[Scott_USN]

Did someone say Thunderbolt?

[rustysi]

ORIGINAL: witpqs

ORIGINAL: rustysi

Don't know the actual answer, but the P-47 was HUGE for a fighter.

Heaviest single engine, single seat fighter of the war. How that may equate to 'size', I know not.

I don't have any links to photos at hand, but apparently it was the Godzilla of fighter planes.

Yeah, the Brits, having flown the sleek Spit, almost from the beginning, laughed at us Yanks when they saw it. They wondered WTF we were going to do with a beast like that. Ah, ye of little faith.[:D]

[RangerJoe]

ORIGINAL: Scott_USN

Did someone say Thunderbolt?

A nice weapon, now build a plane around it that even women can fly . . .

[rustysi]

Been there, done that.[:D]

One young lady, the only person out of two who survived, had to attempt a landing with all the hydraulics being shot out.

[Jorge_Stanbury]

I agree if the USA wanted, they could had made the F4U a high altitude fighter. I mean take a look at the BF109, so many versions, early ones very capable to fight at the low altitudes needed in the eastern front and other versions (later ones) pressurized, with better supercharger and very capable to fight against US bombers and P-51s at high altitude. Typical example would be BF109G5 (high altitude)and G6 (standard) built in parallel during 1943

It is simply that there was no need to build a high altitude Corsair, there were plenty of other planes on that niche that were better for the needs of USAAF whilethe Corsair was perfect for the altitudes needed for the Navy/ Marines. So the fact remains that at high altitude the production F4Us could not compete against a P51 a P47 or a high altitude version 109

[Bearcat2]

3- F4U-1 were converted with a P&W XR-2800-16 B [1 had the -14] and a Birmann turbosupercharger,4 blade prop. The turbosupercharger was installed under the fuselage, which made it unsuitable for Carriers, was designed to be a land based plane only.
13 production models [FG-3] were built in 1945

[bomccarthy]

A turbo could not have been shoehorned into an F4U. Turbosupercharger installations are larger and heavier than mechanically driven auxiliary stage superchargers; so much so that the only two turbosupercharged fighters that made it into large scale production, the P-38 and P-47, were designed from inception around their turbo installations. The P-47's enormous fuselage was determined by the dimensions of the turbo plumbing that ran back to the turbo in the lower rear fuselage and the P-38's twin-boom designed neatly accommodated the turbos situated behind their Allison engines.

The size and weight penalty meant that the turbo's advantage was really above 25,000 ft; below that, the lighter and more compact mechanically driven auxiliary stage worked as well or better.

Production models of the Bf-109 and FW-190 used mechanically driven single stage, variable speed superchargers which gave best performance below 25,000 feet; the versions intended for high-altitude operation used liquid nitrous oxide injection (tank capacity lasted approx 20 minutes), although a few FW-190 prototypes were built with turbos.

The USAAC/USAAF and USN developed different doctrines in the 1920s and 1930s, with the USSAC/USAAF focused on high-altitude operations, 25-35k ft. The USN, on the other hand, focused on operations up to 25,000 feet. Consequently, the USN pioneered the use of the mechanically driven auxiliary stage supercharger in fighters -- the F4F-3 was in production and service before the Spitfire VIII or IX (prior model Spitfires had single-stage superchargers).

Rolls Royce refused to consider turbosupercharging for the Merlin; Rolls engineers calculated that the thrust from properly designed exhaust stacks made up for the power loss at high altitudes.

[RangerJoe]

ORIGINAL: bomccarthy

A turbo could not have been shoehorned into an F4U. Turbosupercharger installations are larger and heavier than mechanically driven auxiliary stage superchargers; so much so that the only two turbosupercharged fighters that made it into large scale production, the P-38 and P-47, were designed from inception around their turbo installations. The P-47's enormous fuselage was determined by the dimensions of the turbo plumbing that ran back to the turbo in the lower rear fuselage and the P-38's twin-boom designed neatly accommodated the turbos situated behind their Allison engines.

The size and weight penalty meant that the turbo's advantage was really above 25,000 ft; below that, the lighter and more compact mechanically driven auxiliary stage worked as well or better.

Production models of the Bf-109 and FW-190 used mechanically driven single stage, variable speed superchargers which gave best performance below 25,000 feet; the versions intended for high-altitude operation used liquid nitrous oxide injection (tank capacity lasted approx 20 minutes), although a few FW-190 prototypes were built with turbos.

That must have been funny if there was a leak into the cockpit!


The USAAC/USAAF and USN developed different doctrines in the 1920s and 1930s, with the USSAC/USAAF focused on high-altitude operations, 25-35k ft. The USN, on the other hand, focused on operations up to 25,000 feet. Consequently, the USN pioneered the use of the mechanically driven auxiliary stage supercharger in fighters -- the F4F-3 was in production and service before the Spitfire VIII or IX (prior model Spitfires had single-stage superchargers).

Rolls Royce refused to consider turbosupercharging for the Merlin; Rolls engineers calculated that the thrust from properly designed exhaust stacks made up for the power loss at high altitudes.

[Jorge_Stanbury]

ORIGINAL: bomccarthy
Production models of the Bf-109 and FW-190 used mechanically driven single stage, variable speed superchargers which gave best performance below 25,000 feet; the versions intended for high-altitude operation used liquid nitrous oxide injection (tank capacity lasted approx 20 minutes), although a few FW-190 prototypes were built with turbos.

the early versions, the later ones simply got a bigger super charger

from https://www.chuckhawks.com/evolution_ME-109.html
"In January 1944, the DB605AS with a larger supercharger was introduced. It was a little slower at low altitude, but above 23,400 ft, the AS-equipped models became increasingly superior, reaching 417 mph at 27,000 ft. This engine was not fitted for GM1"

that is why I think F4U could had better altitude performance if they needed to pursue it; not by adding turbo, which was too complicated for an existing design but by another solution; maybe a larger supercharger (like later BF109) or by 2-speed/ 2-stages (like P-51) or two superchargers (like P-63) or something else

[PaxMondo]

ORIGINAL: bomccarthy

A turbo could not have been shoehorned into an F4U. Turbosupercharger installations are larger and heavier than mechanically driven auxiliary stage superchargers; so much so that the only two turbosupercharged fighters that made it into large scale production, the P-38 and P-47, were designed from inception around their turbo installations. The P-47's enormous fuselage was determined by the dimensions of the turbo plumbing that ran back to the turbo in the lower rear fuselage and the P-38's twin-boom designed neatly accommodated the turbos situated behind their Allison engines.

The size and weight penalty meant that the turbo's advantage was really above 25,000 ft; below that, the lighter and more compact mechanically driven auxiliary stage worked as well or better.

Production models of the Bf-109 and FW-190 used mechanically driven single stage, variable speed superchargers which gave best performance below 25,000 feet; the versions intended for high-altitude operation used liquid nitrous oxide injection (tank capacity lasted approx 20 minutes), although a few FW-190 prototypes were built with turbos.

The USAAC/USAAF and USN developed different doctrines in the 1920s and 1930s, with the USSAC/USAAF focused on high-altitude operations, 25-35k ft. The USN, on the other hand, focused on operations up to 25,000 feet. Consequently, the USN pioneered the use of the mechanically driven auxiliary stage supercharger in fighters -- the F4F-3 was in production and service before the Spitfire VIII or IX (prior model Spitfires had single-stage superchargers).

Rolls Royce refused to consider turbosupercharging for the Merlin; Rolls engineers calculated that the thrust from properly designed exhaust stacks made up for the power loss at high altitudes.

Correct. I've got photos from the visit I made with Zulu to the Air&Space museum somewhere. The twincharger is physically a lot longer. Not a weight issue, but a physical space issue. If I can dig up the photos I will post … I'm an engine nut so about the only photos I took were the engines. [8D]

[Ian R]

ORIGINAL: bomccarthy

A turbo could not have been shoehorned into an F4U. Turbosupercharger installations are larger and heavier than mechanically driven auxiliary stage superchargers; .....

Rolls Royce refused to consider turbosupercharging for the Merlin; Rolls engineers calculated that the thrust from properly designed exhaust stacks made up for the power loss at high altitudes.

According to David Donald the production run of the F4U-1 was over 8,000 (4102 by Vought with the corresponding models from Goodyear totalling 3808, and Brewster 735.) During the production run 500 major, and 2500+ minor engineering changes were made - averaging almost 1 change per three aircraft completed.

He also confirms what Bearcat said, that they did jam a turbo-supercharger in there to see what happened. He refers to a "handful" of F4U-3 builds with the XR-2800-16 and what he describes as a turbo-supercharger, "ram air being admitted via a large ventral duct."

That said, the Corsair did have the "jet-thrust exhaust stacks" in the collar behind the cowling, but those only give maybe 3 or 4% performance increment, less than than the Meredith effect from the P51s ventral radiator.

[bomccarthy]

ORIGINAL: Jorge_Stanbury

ORIGINAL: bomccarthy
Production models of the Bf-109 and FW-190 used mechanically driven single stage, variable speed superchargers which gave best performance below 25,000 feet; the versions intended for high-altitude operation used liquid nitrous oxide injection (tank capacity lasted approx 20 minutes), although a few FW-190 prototypes were built with turbos.

the early versions, the later ones simply got a bigger super charger

from https://www.chuckhawks.com/evolution_ME-109.html
"In January 1944, the DB605AS with a larger supercharger was introduced. It was a little slower at low altitude, but above 23,400 ft, the AS-equipped models became increasingly superior, reaching 417 mph at 27,000 ft. This engine was not fitted for GM1"

that is why I think F4U could had better altitude performance if they needed to pursue it; not by adding turbo, which was too complicated for an existing design but by another solution; maybe a larger supercharger (like later BF109) or by 2-speed/ 2-stages (like P-51) or two superchargers (like P-63) or something else

The F4U (and F6F) did have two-stage supercharging, like the P-51 and P-63, but optimized for "medium altitudes", with a critical supercharger altitude of 22,000 feet (compared to 27,000 feet for the P-51B). Optimizing it for a higher critical altitude would have reduced performance at medium altitude; this showed up in comparison tests between the F4U-1 and the P-51B.

The P-47 and P-51B/D were developed to operate at the same altitude as the intended bombing altitude of the B-17 and B-24 (27,000 ft +); the Navy fighters were intended to operate at altitudes where enemy aircraft were typically encountered (below 25,000 feet). Ironically, USAAF lowered bombing altitudes in 1944, as studies showed that bombing accuracy increased significantly below 25,000 feet. By the Spring of 1945, even B-29s were dropping their bombs from 20,000 to 25,000 feet during their daylight raids over Japan, even though they were designed to operate close to 30,000 feet.

[bomccarthy]

ORIGINAL: Ian R

ORIGINAL: bomccarthy

A turbo could not have been shoehorned into an F4U. Turbosupercharger installations are larger and heavier than mechanically driven auxiliary stage superchargers; .....

Rolls Royce refused to consider turbosupercharging for the Merlin; Rolls engineers calculated that the thrust from properly designed exhaust stacks made up for the power loss at high altitudes.

According to David Donald the production run of the F4U-1 was over 8,000 (4102 by Vought with the corresponding models from Goodyear totalling 3808, and Brewster 735.) During the production run 500 major, and 2500+ minor engineering changes were made - averaging almost 1 change per three aircraft completed.

He also confirms what Bearcat said, that they did jam a turbo-supercharger in there to see what happened. He refers to a "handful" of F4U-3 builds with the XR-2800-16 and what he describes as a turbo-supercharger, "ram air being admitted via a large ventral duct."

That said, the Corsair did have the "jet-thrust exhaust stacks" in the collar behind the cowling, but those only give maybe 3 or 4% performance increment, less than than the Meredith effect from the P51s ventral radiator.

The XF4U-3 used a Birmann turbosupercharger, rather than a GE-designed turbo that was used in all US production aircraft with turbos; I am assuming that development problems with this turbo influenced the decision not to proceed with production, along with the test results that showed no performance improvement at the typical combat altitudes.

Re jet thrust from the exhaust: Rolls Royce calculated that 200 thrust horsepower could be realized at 24,000 feet and 400 mph. After the war, Wright used engine exhaust to spin 3 large turbines in the R-3350 Turbo Compound engine - these turbines spun gears that were connected directly to the crankshaft, adding 800 hp to an engine already producing 3,000 hp. Four such engines powered all DC-7s and Super Constellations.

[Ian R]

I was just watching a show on the history channel, that featured an interview with Robin Olds.

He stated quite firmly that in WW2, flying a P38, "I could out maneuver the 109 at the altitudes we flew".

The show at least loosely referred to an ME-109 wit 1 x 30mm and 2 x MG armament, but it was by no means clear if Olds was talking about one of the heavy hitter sub-types with diminished performance.

[Macclan5]

ORIGINAL: Scott_USN

Yeah they lost before they even started production wise but that is not really the point. They still had capable and in some respects better planes, the F4U was supercharged it was not turbocharged as was the P47 but could have easily had the intercooler turbocharger of the P47 it was the same engine in both planes. 30k feet was not all that important in the Pacific. Water injection in the 1A model gave it another 250hp. There was nothing in the Pacific that really could put up much of a challenge to such a plane. I don't think it is simplistic at all I think it very complicated but the point was simplistic I love the Navy war birds (Especially F4U) and have always wondered how they would have fared against German fighters.

And here you and I respectfully disagree. [8D]

The Americans could have flown nothing but'upgraded P39's / P40's' till 1945 and still they would have won air superiority over Europe. Eventually - at a higher cost - but eventually.

There is an old adage around these forums. Stalin said "quantity is its own form of quality".

I do not think that the F4U with a super charger or turbo charger or whatever modifications were necessary - and the US would have made necessary modifications - makes any difference at all.

--

In the "what if" historical banter that often accompanies a lot of gamer sites - "what if the Nazi's had recognized the potential of / produced enough of / capitalized on the ME262" ? They could have won the war !!

Mehh...

Would have the ME262 really turned the tide of the Red Army - especially into Romanian Oil fields? Germany imported >80% of its oil from Russia prior to Barbarossa and failed... where is the oil / gas / resources to build thousands more ME262 and fly them? Would have the ME262 shut down 8th Air force Bombing ? Completely ? Would have the ME262 stopped Normandy completely....? It would have made a difference certainly / timing / losses. But won the war ?

So often these hypothetical debates focus on the deployment of 1 weapon type verses another and ignore the fact that Japanese / German militarism was focused on short wars due to their "national and genetic superiority" as warriors. That victory was inevitable. But both Japan and Germany started the war at severe disadvantages in terms of access to oil and raw materials for a protracted war of production and attrition - further manpower replacements/population bases were also too small and their mobilization rates were unsustainable. Therefore loss was inevitable. The tools of getting the job done no longer matter after the initial conquering wave lost its momentum due to the lack of sustainability in logistics.

[Jorge_Stanbury]

ORIGINAL: Ian R

I was just watching a show on the history channel, that featured an interview with Robin Olds.

He stated quite firmly that in WW2, flying a P38, "I could out maneuver the 109 at the altitudes we flew".

The show at least loosely referred to an ME-109 wit 1 x 30mm and 2 x MG armament, but it was by no means clear if Olds was talking about one of the heavy hitter sub-types with diminished performance.

It will depend a lot on what version of P-38 he fought against what version of 109. Early P-38s were not that great in Europe/ Mediterranean and were mostly outclassed by 109s and 190s

Also, he likely faced a 109-G6 as this was the most numerous version built and it is the 1st that allows for the 30mm motor cannon; I doubt he could had outmaneuvered a late war 109-K4 or 109-G14/ G10

[rustysi]

resources to build thousands more ME262 and fly them?

With the resources Germany had available she could not manufacture its engines with the necessary alloys (in quantity) to last more than 10-20 hours of flight time. Failure, not a war winner.

Apparently she did know what was needed, I've read at least one test engine ran for 250 consecutive hours. Just didn't have the materials. Thus of some 1400 built no more than about 100 were operational at any given time.

[bomccarthy]

ORIGINAL: Jorge_Stanbury

ORIGINAL: Ian R

I was just watching a show on the history channel, that featured an interview with Robin Olds.

He stated quite firmly that in WW2, flying a P38, "I could out maneuver the 109 at the altitudes we flew".

The show at least loosely referred to an ME-109 wit 1 x 30mm and 2 x MG armament, but it was by no means clear if Olds was talking about one of the heavy hitter sub-types with diminished performance.

It will depend a lot on what version of P-38 he fought against what version of 109. Early P-38s were not that great in Europe/ Mediterranean and were mostly outclassed by 109s and 190s

Also, he likely faced a 109-G6 as this was the most numerous version built and it is the 1st that allows for the 30mm motor cannon; I doubt he could had outmaneuvered a late war 109-K4 or 109-G14/ G10

He could outturn any Bf-109 below 15,000 feet. Above 20,000 feet it would depend on whether he was flying a P-38F/H/G or a P-38J/L.

But trying to compare one fighter type against another of the same generation is somewhat pointless (unless the speed differential is vast). There are so many variables, especially individual pilot skill and experience. At his peak, Robin Olds could have taken on any Bf-109 while flying a P-39, or could have been shot down by a Ki-27 Nate while flying a P-51, if he was having a bad day. (Tommy McGuire stalled his P-38 in a hard turn at less than 300 mph and 200 ft while still carrying his drop tanks).

Most important was that Luftwaffe training had deteriorated severely by mid 1944, and the few remaining aces faced overwhelming numbers, such that survival became more important than victories. And an inexperienced pilot trying to fly a Bf-109G, or K, was often asking for trouble -- a Luftwaffe test pilot described the handling characteristics of the later Bf-109s during a landing approach as "malicious."

[bomccarthy]

ORIGINAL: rustysi

resources to build thousands more ME262 and fly them?

With the resources Germany had available she could not manufacture its engines with the necessary alloys (in quantity) to last more than 10-20 hours of flight time. Failure, not a war winner.

Apparently she did know what was needed, I've read at least one test engine ran for 250 consecutive hours. Just didn't have the materials. Thus of some 1400 built no more than about 100 were operational at any given time.

They had the right material for that test engine, but that was it. Junkers decided to get around the short lifespan by building lots of engines - lots and lots of engines - replacing them every 10-20 hours. They apparently didn't figure out how they were going to move these multitudes of spare engines from the factories to the airfields, once the 8th AF shattered Germany's rail network.

[Ian R]

ORIGINAL: Macclan5

Would have the ME262 really turned the tide of the Red Army - especially into Romanian Oil fields?

The irony is that the Jumo 004 ran on J2 produced from coal, and didn't need high octane avgas.