F5F or F4F. Did the U.S. Navy make the right choice?

Both of these fighters were built by Grumman. The F5F's performance was as good as the Grumman F6F Hellcat which wasn't introduced into service until early 1943. Because it wasn't possible to have the single engined Hellcat or Corsair put into service earlier because their engines (Pratt and Whitney R-2800s) weren't available in the 1940-1941 time frame.

By the simple measure of putting 2 Wright R-1820s (a very reliable engine) on a new airframe it could have been possible to have Hellcat performance level airplanes being put into squadron service in 1941 instead of the F4F. And a solid Grumman design too. Imagine what tactics Jimmy Thach and his peers would have developed with its superior performance.

But the U.S. Navy said no thanks. They preferred the single engine F4F. I would think the biggest drawback with the F5F Skyrocket was the carrier air groups would have had to conduct operations with a smaller number of fighters because the F5F would need more deck space even though the outer wing panels did fold back over the engines. And of course they would require more maintenance hours and parts. Was the higher expense still a big concern after the Fall of France and the Two-Ocean Navy Act?

But would the advantages of having a superior and faster fighter than the Zero with better survivability due to its two engines outweigh the disadvantage of having smaller fighter squadrons? Another plus to consider is due to their light weight and high power loading I think the F5F would have been able to operate from the escort carriers with their shorter flight decks and slower speeds. Maybe GM could/should have been building FM Skyrockets in 1943 to 1945.

https://en.wikipedia.org/wiki/Grumman_XF5F_Skyrocket
800px-The_latest_type_of_a_Grumman_Navy_fighter_-_NARA_-_195921.jpg



https://en.wikipedia.org/wiki/Grumman_F4F_Wildcat
800px-F4F-3_new_pitot_tube_of_later_model.jpg


So, was this a squandered opportunity for an earlier advantage in the Pacific War or a costly mistake avoided?
 
The factor of hangar space comes in to the equation you could hold three Wildcats in an aircraft carrier hanger for the space of two Skyrockets. This becomes even more critical on escort carriers.
A wiser decision would have to been to let US Marine corps operate Skyrockets from Land bases. The extra payload would have been very useful in ground support missions and a higher speed,rate of climb and heavy armament would have been better in Intercepting attacking bombers.
GM would not have liked to have built the skyrocket because it would have taken resources away from their P-75 Eagle project.
 

thorr97

Banned
Go with the ultimate refinement of the Skyrocket - what Grumman called the P-50 - and you'd really have had something. Grumman learned a lot in its test flights of the XF5F and you can see that in the various changes to its engine nacelles and such. Elongating the nose not only gave more room for firepower and ammunition it also meant less drag and better handling, overall.

That's the version that both the Navy and the Army could've gone with!
 
The factor of hangar space comes in to the equation you could hold three Wildcats in an aircraft carrier hanger for the space of two Skyrockets. This becomes even more critical on escort carriers.
A wiser decision would have to been to let US Marine corps operate Skyrockets from Land bases. The extra payload would have been very useful in ground support missions and a higher speed,rate of climb and heavy armament would have been better in Intercepting attacking bombers. ...

Im reflecting on how that would play out at places like Wake, Midway, Guadalcanal... Not a significant difference in the grand cosmic scheme in the first two, just a few more Japanese aircrew lost. But over the Solomons in the Autumn air battles it can first improve the attrition of the Japanese air wing, and second cause both the Army AF & Navy to reconsider their aircraft selections for 1943-45.
 

marathag

Banned
The factor of hangar space comes in to the equation you could hold three Wildcats in an aircraft carrier hanger for the space of two Skyrockets. This becomes even more critical on escort carriers.
First flight, March 1940. Grumman's first wing folding aircraft
6035984843_c5c6cd71f9_o.jpg

The folding wing Wildcat didn't reach squadron service til June, 1942
 
Im reflecting on how that would play out at places like Wake, Midway, Guadalcanal... Not a significant difference in the grand cosmic scheme in the first two, just a few more Japanese aircrew lost. But over the Solomons in the Autumn air battles it can first improve the attrition of the Japanese air wing, and second cause both the Army AF & Navy to reconsider their aircraft selections for 1943-45.

The fighters still need to be brought to the bases by aircraft carrier. Does the higher performance and armament of the F5F outweigh the lesser numbers of them that could be brought to the Solomons at any one time? And armament-wise, how much real difference is there between the F5F and the F4F-4? Oh, I just looked at the wiki page for the XF5F - the armament is listed as being the same as the F4F-3, 4 50-cal machine guns.
 

Driftless

Donor
The F5F was a missed opportunity, IMO. Had they worked out the early kinks and sorted out an alternative production line, that plane could have been a real potent high-performance weapon for the Navy. If the Navy balks at the twin-engine maintenance issues, then farm the plane out to the Marines (as noted above). If that's the case, then bring the Skyrocket back into use as a carrier born invasion CAS plane, at least till the Corsair gets ready.

*edit* Could a fighter-bomber version have been worked up? With those two big engines, there should have been sufficient power to carry a useful bomb load, and self-protect once the ordnance is delivered.
 
The prototype was from all descriptions a delight to fly. BUT it was unarmed; by the time you add armament and all the other needed equipment not fitted to the prototype how does that affect performance?
 
The fighters still need to be brought to the bases by aircraft carrier. Does the higher performance and armament of the F5F outweigh the lesser numbers of them that could be brought to the Solomons at any one time? And armament-wise, how much real difference is there between the F5F and the F4F-4? Oh, I just looked at the wiki page for the XF5F - the armament is listed as being the same as the F4F-3, 4 50-cal machine guns.

Armament is never set in stone. I suspect six HMG, or two HMG & two cannon would be just as likely by the time this bird reached combat.

Theres three capabilities over the P40 & F4F this F5F needs to be worth the effort. 1. Can it climb to medium & high altitudes faster than the other common US fighters in combat in 1942? 2. Would it be fast enough to evade the Zero in pursuit. Equal or better dive speed to the P40 or F4F is ok here, straight line acceleration is better. 3. Robust. Can it hold together as well as the others, or will it fold under the fire of the Japanese fighters guns. 4. Bonus if it can turn significantly better than the other US fighters of 1942. I doubt it could outturn a Zero, but close is a game changer. The Zeros advantage was in low to medium speed turns. If this thing has the ability to out turn Japanese fighters at high speeds sophisticated tactics open up to the US pilots who survive & learn.
 

marathag

Banned
1. Can it climb to medium & high altitudes faster than the other common US fighters in combat in 1942?
per wiki, 4000fpm The initial climb rate on the Hawk 75 was 3400, XP-40 was 3070, P-40D was down to 2580. F2A-1 Buffalo was 2600
F4F-3 was 2050, but up to 3650 on the FM-2, back to lighter weight of the original, and more powerful two stage engine. The Xf4F poor climb is one of the reasons Brewster got orders for the Buffalo, that got worse with each revision.

2. Would it be fast enough to evade the Zero in pursuit. Equal or better dive speed to the P40 or F4F is ok here, straight line acceleration is better.
383mph at sea level, awesome if true. Powerdive test was 505mph, as good as the Hawk 75. But anything with a turning prop will hit around .8 critical mach speed and any speed past that can be chalked up to compressability weirdness on the pitot tube. P-38 ran into it at .68

3. Robust. Can it hold together as well as the others, or will it fold under the fire of the Japanese fighters guns.
It's made by Grumman. Everything they made seemed to be rugged, that why they got the nick _Ironworks_

4. Bonus if it can turn significantly better than the other US fighters of 1942.
with no torque difference thanks to the twin engine setup, that's an advantage. But it's a twin so wouldn't rollas fast, but still faster than the A6M, terrible roll rate at speed
 

thorr97

Banned
per wiki, 4000fpm The initial climb rate on the Hawk 75 was 3400, XP-40 was 3070, P-40D was down to 2580. F2A-1 Buffalo was 2600
F4F-3 was 2050, but up to 3650 on the FM-2, back to lighter weight of the original, and more powerful two stage engine. The Xf4F poor climb is one of the reasons Brewster got orders for the Buffalo, that got worse with each revision.

That 4,000 fpm climb rate was how it earned the nickname "Skyrocket" and it was also why the Army was even willing to admit the possibility of a chance of a suggestion of an interest in one of the Navy's airplane designs.
 
Having read up on some of the many problems that the pre/early war US armed forces branches were having, individually and when working together, I wonder if the OTL development of the F5F might have generated interest in joint projects for intersperse compatible aircraft types. So lets say that the government steps in, and mandates sometime prewar, that here needs to be some operational squadrons that share the same air frames, so USAAC, USN & US Marines all have to operate at least one common fighter type, such that, in time of need, each branch would already have had a least one squadron that could be based from the other services facilities, be they land or sea based.

Let's say that the F5F was a type seen as potentially useful to all three branches, so island based, homeland based, and carrier based squadrons are up and running in time for the deployments for midway. Would all three branches having a squadron of FSF's at midway have made a difference? Would the existence of the F5F mean that the Buffalo's wouldn't even be at midway at all?
 

McPherson

Banned
Both of these fighters were built by Grumman. The F5F's performance was as good as the Grumman F6F Hellcat which wasn't introduced into service until early 1943. Because it wasn't possible to have the single engined Hellcat or Corsair put into service earlier because their engines (Pratt and Whitney R-2800s) weren't available in the 1940-1941 time frame.

By the simple measure of putting 2 Wright R-1820s (a very reliable engine) on a new airframe it could have been possible to have Hellcat performance level airplanes being put into squadron service in 1941 instead of the F4F. And a solid Grumman design too. Imagine what tactics Jimmy Thach and his peers would have developed with its superior performance.

But the U.S. Navy said no thanks. They preferred the single engine F4F. I would think the biggest drawback with the F5F Skyrocket was the carrier air groups would have had to conduct operations with a smaller number of fighters because the F5F would need more deck space even though the outer wing panels did fold back over the engines. And of course they would require more maintenance hours and parts. Was the higher expense still a big concern after the Fall of France and the Two-Ocean Navy Act?

But would the advantages of having a superior and faster fighter than the Zero with better survivability due to its two engines outweigh the disadvantage of having smaller fighter squadrons? Another plus to consider is due to their light weight and high power loading I think the F5F would have been able to operate from the escort carriers with their shorter flight decks and slower speeds. Maybe GM could/should have been building FM Skyrockets in 1943 to 1945.

https://en.wikipedia.org/wiki/Grumman_XF5F_Skyrocket
800px-The_latest_type_of_a_Grumman_Navy_fighter_-_NARA_-_195921.jpg



https://en.wikipedia.org/wiki/Grumman_F4F_Wildcat
800px-F4F-3_new_pitot_tube_of_later_model.jpg


So, was this a squandered opportunity for an earlier advantage in the Pacific War or a costly mistake avoided?

While I am a fan of the ATL F5F that I am using in ...Those Marvelous Tin Fish: The Great Torpedo Scandal Avoided, that F5F is only possible because this "gentleman", John Henry Towers, is not Chief of Bu-Air in that ATL to foul things up. the F5F I envisioned is an aircraft carrier rated P-50 with arrestor gear, the folding wings and the performance parameters of the XF5F (added weight does this.).

p50-6.jpg


The reason the RTL XF5F was a showstopper is because it was a tail wheel dragger and the pilot could not see past the main wing leading edge to line the aircraft nose on the center of the trap lane on a flattop. It also had wicked point drift and considerable sideslip in a crosswind. Tricycle gear and extending the barrel nose solved a lot of these sins, but conservative WW I era Opie-dopes (read Elmer Fudds like John Towers) could not see the Grumman engineering arguments for their own stuck-in-the-mud-biplane Langley experiences. To those three starred cretins, it took a WHACK upside the head to go from the F2A to the F4F. Imagine what kind of miracle it would take to go to a Tigercat? WW II.

1920px-Grumman_F7F-3N_Tigercat_2007.jpg


The Germans had a similar choice...

fw-187.jpg


In the end their Elmer Fudd was named Erhard Milch. Notice that he blamed Fatso for HIS mistakes? Towers never did admit he screwed up either.
 
Having read up on some of the many problems that the pre/early war US armed forces branches were having, individually and when working together, I wonder if the OTL development of the F5F might have generated interest in joint projects for intersperse compatible aircraft types. So lets say that the government steps in, and mandates sometime prewar, that here needs to be some operational squadrons that share the same air frames, ...

I'm thinking its more likely the AAC or AAF get serious about hot rodding the P38 so it is the aircraft for curb stomping the Axis AF in 1943, vs the P51 a bit later. The P38 as prototyped had a lot of potential that was not pursued as it might have been.

per wiki, 4000fpm The initial climb rate on the Hawk 75 was 3400, XP-40 was 3070, P-40D was down to 2580. F2A-1 Buffalo was 2600
F4F-3 was 2050, but up to 3650 on the FM-2, back to lighter weight of the original, and more powerful two stage engine. The Xf4F poor climb is one of the reasons Brewster got orders for the Buffalo, that got worse with each revision. ...

That climb rate, even if only equal to the Hawk 75 after combat configured is still a big plus. However it still does not put it in the same class as the A6M2 Model 21 with a climb rate of 4500 fpm
 
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McPherson

Banned
I'm thinking its more likely the AAC or AAF get serious about hot rodding the P38 so it is the aircraft for curb stomping the Axis AF in 1943, vs the P51 a bit later. The P38 as prototyped had a lot of potential that was not pursued as it might have been.

That climb rate, even if only equal to the Hawk 75 after combat configured is still a big plus. However it still does not put it in the same class as the A6M2 Model 21 with a climb rate of 4700 fm

My data reads 15.7 m/s (3,090 ft/min). The Skyrocket beats that.

Francillon, Rene J. (1966). Aircraft Profile #129: The Mitsubishi A6M2 Zero-sen (September 1982 Canada reprint ed.). Berkshire: Profile Publications.
 
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