If the Hughes H-1 would have been made into a fighter...

[davparlr]

Unfortunately, I am convinced that You have not yet succeeded to prove this assumption beeing correct.

I have addressed all of these issues in previous post. I will recap succinctly.

How big is the new wing?

The larger wing is the same wing that Hughes used to set his cross country record in the H-1, wing span of 32 ft, 191 sqft area.

What is the difference in drag related to the bigger fuselage?

I estimated a 24 mph reduction in top speed at SL for the increased fuselage diameter

"Install P&W R-1830 (1000 hp), increasing form area by 1.95 sqft and weight by 200 lbs (?).
Airspeed 328 mph SL (weight impact on airspeed negligible) (drag formulas)"

What was the original powerlevel at the H-1´s record flights?

Unknown. For the top speed record it was probably slightly below max output of 1000 hp. Hughes stated that he could go faster so he felt more power could be applied. For the cross country record it was probably at normal rated HP or below, 700 hp?.

Remember, it took basically a simple Bf-109D airframe very little to achieve a low level record speed of 610 km/h. On 11 November 1937 the Bf 109 V13 flown by Messerschmitt's Chief pilot Dr. Hermann Wurster, and powered by an 1,650 hp (1,230 kW) DB 601R racing engine set a new world air speed record for Landplanes with piston engines to 610.55 km/h (379.38 mph) at low level and won the title for Germany for the first time. The V-13´s modification was the Db-601R engine, a special treated surface and the removement of equipment and weapons. Nevertheless, the same Bf-109D but in an operational condition was unable to hit 300 mp/h at SL with a normal rated engine.

The V-13 engine, had a greatly overblown engine that had to be scrapped after the flight. 1650 hp (81% increase) was NOT 'very little'. With 65% more power than the H-1, the specially prepared V-13 was only capable of being 37 mph faster. This really doesn't say much unless you compare the H-1 with 1650 hp. I am sure someone can calculate the theoretical speed of the H-1 with 1650 hp given that it made 353 mph with 1000 hp. Knowing the propaganda desire of Germany, I suspect the Bf-109D was, in reality, highly modified. Remember, the Bf-109R was an entirely different aircraft than the Bf-109.

As far as I know, the H-1´s special engine was also tuned from 700 hp to over 1000 hp, altough the exact powerlevel at the flights are still unkown to day.

The engine in the H-1 was a standard R-1535 engine, as claimed by Howard Hughes, that had been tuned to use 100 octane fuel, a technique used extensively in WW2. Hughes was proud of this. He stated that all the aircraft that had flown faster than the H-1 up to that time, the Supermarine float plane racers, had special short lifetime engines. There is no account that the engine was changed between the high speed record and the cross country record, although it could have been. In any event I proposed the use of the R-1830 engine, a well proven engine used in the F4F and capable of 1200 hp in 1939.

The wing area was just 138 ft^2 in the original design. The adjusted bigger wing area of Your design is around 190 ft^2. This alone translates into 38.5% more wing area.
With a 1200 hp rated engine at Sealevel and the given increase in wing area, my physics show no realistic probability to exceed a speed of 300 mp/h at Sea level. Actually, with this increase in wing area, You would need to pull at least 1330 hp out of the engine to make 330 mp/h at SL plausible. With the same 1000 hp engine, the H-1 would have been hardly pressed to hit 250 mp/h at SL with the bigger wings, everything else staying identical to the H-1 Special. And this does not include the increased drag caused by the bigger diameter fuselage, equipment, raised canopy or gunports. All included, a top speed of ca. 290 mp/h seems more realistic to me (there is some likelyhood that more exhoust thrust may be generated). This also puts the H-1 closer along the lines of the performance drops known from the Bf-109D and Spitfire.

I am not an aero engineer so I must confess lack of expertise, however I am confused by this and how you arrived at the values you did. I think your numbers are low. According to centiennialofflight.com, the percentage of drag of the wing of a Bf-109 is about 37.5% (not including induced drag) of the total drag of the aircraft. The increase of drag due to the larger wing should be compared to the total drag, which would be a less percentage than what you calculated. Also, with an increase of wing span, the level flight induced drag would be less than the short wing version, something I did not try to calculate, it would not be much at high speeds. In addition, on comparing to other aircraft, your large drop in airspeed due to a larger wing does not seem to hold. The Ta-152H with a wingspan of 47'4" and an area of 250 sqft is only about 6 mph slower at SL than the Ta-152C, which has a wingspan of 36'1" and an area of 210 sqft., and roughly the same hp (the Ta-152C actually has more hp). Also, the P-47N with a wingspan of 42'7" and an area of 322 sqft., has the same SL top speed as the P-47M with a wingspan of 40'9" and an area of 308 sqft, and with the identical engine. In addition, the Spitfire has a 37.5% larger wing than the Bf-109, yet both have the same SL top speed with equivalent Hp. I doubt that the elliptical wing could make up that 37.5% difference. Larger wings and more area, in themselves, seem to have minimal impact to these aircraft so I fail to see why it would have had such a large impact to the H-1. Perhaps the discrepancy is due to the way referenced area is defined. Doing a recalculation based on separate impact to the wing and fuselage and then to the overall drag, I came out with a number higher than my original. But, considering my level of intellect on drag, (it gives me a headache) I'll still stick with my original numbers.

Dick Palmer, principal designer of the H-1, was a family friend. I knew him fairly well, talked to him at length about the H1. He told me the bird was almost ready to fly before Hughes let him know that he, Hughes, was going to fly it. Dick was worried. He thought Hughes was competent enough, but it was a new design, and Hughes was signing the pay checks, so Dick both assumed and hoped Hughes was going to have a professional test pilot do the flying.
I asked him if it was a difficult or dangerous plane to fly. He thought not. Especially with the X-country long wings. He specifically said stalls were NOT violent, abrupt or in any way unusual.

Wow. I would have loved to talk to him. I think the H-1 was a fascinating aircraft and I have a lot of questions about it he would have been able to answer, namely everything we have been trying to answer here.

I also asked him if the H1 could have been made into a military airplane. Answer: "That was the idea."

This was my assumption. And, I think Hughes would have built a high performance fighter.

I've always thought the H1 may be the most beautiful machine of any kind ever made by anyone. I have spent many hours just looking at in the old Smithsonian. I was sorry I never got to see the Wright replica, and even sorrier that it and Wright crashed.

My feelings too!

Let me re-phrase my question. What if the H-1 had been designed around the Allison V-1710 from the very beginning? Less frontal area, potentially an even cleaner airframe. It would have been a much better prospect for a fighter if it already had a desirable power plant, rather than the need for an iffy engine swap that would have unpredictable results.

With the lines and the shape of the plane already determined, all that would remain is stressing it, putting a standard Allison (rather than an overboosted racing engine that might have been pushed to 1600 horses for the speed record) in it and hanging guns, armor and self sealing tanks on it, the exact same process that the Spit and the 109 had to go through.

Sorry to divert your thread. The V-1710 would have added several hundred pounds to the H-1 and therefore some maneuvering impact. There is no reason to believe that the H-1 could have been built to the weight of the Spitfire. The more slim design could have aided the top speed. If we look at the Vultee Vanguard prototype and the P-66, we could get a glimpse of what performance change could be obtained. The P-66 was designed by the same man who helped Hughes with the H-1 (see tommayer entry above). It was bulkier, however. The Vanguard was the basically the same plane with a streamlined fuselage covering an R-1830, both had the same engine. The top speed of the P-66 was 340 mph and the top speed of the Vanguard was 358 mph. It is apparent that the V-1710 most likely would have improved the H-1 max speed, but it would have had the same altitude problem as the P-39/40.

 

[Shortround6]

It had fixed cantilever legs. Would that make a difference?

The fixed cantilever legs won't make any difference.

What makes a difference is the the Gladiator used internally sprung wheels, see:

components company | aircraft components | shock absorber | 1931 | 1207 | Flight Archive

vrs using the side walls of of the tire as the spring/shock absorber mechanism.

Another difference is the higher landing speeds of the H-1 vrs the biplane.

 

[Shortround6]

The larger wing is the same wing that Hughes used to set his cross country record in the H-1, wing span of 32 ft, 191 sqft area.

Do you have a source for this area?

"Install P&W R-1830 (1000 hp), increasing form area by 1.95 sqft and weight by 200 lbs (?).
Airspeed 328 mph SL (weight impact on airspeed negligible) (drag formulas)"

The 200lb difference is very doubtful and in any case applies only to the dry weight of the engine and not the difference between installed weight of the POWER PLANTS. Increased weight of propeller, cowlings, exhaust and such are not being taken into account. Perhaps not a really big deal in straight line speed it is a factor in climb performance.

The engine in the H-1 was a standard R-1535 engine, as claimed by Howard Hughes, that had been tuned to use 100 octane fuel, a technique used extensively in WW2.

Just what was this "tuning"?
Different timing?
Different heat range spark plugs?
Higher octane or performance number fuel allows higher boost without detonation. This is the real difference. modifications like timing and spark plugs help with back firing and local hot spots causing detonation.
Higher boost needs better cooling in order to sustain power.
Solved with the larger R-1830 and a new, heavier cowling

The Hughes has a major problem with vision;

http://www.warbirdaeropress.com/articles/Taichi/01NewT/Hughes_H1B_profiles.jpg

The problem isn't the height of the cockpit over the fuselage immediately in front of the cockpit but the height of the canopy (or pilots line of sight ) over the cowl which is only going to get worse with a larger engine. Without a major change in cockpit height deflection shooting is going to be near impossible.

See P-66/vangaurd photo:

Vultee 48

Could Hughes have designed a fighter? yes.
Could it have been based on the H-1 rather than modified from it? Yes.

It just would have needed a bigger, fatter engine, a larger cowl, a fatter fuselage if cowl guns are fitted. a larger tail to compensate for the larger areas ahead of the CG, a taller canopy/fuselage for forward vision.
New landing gear and a new wing construction even if external dimensions and airfoil were the same. Wing structure would have to be modified for wing guns, at least somewhat. Cockpit could be moved forward into racer fuel area to help with vision problem.

You wind up with not much left except a general concept and some details like the wing leading edge intakes and flush riveting.

 

[jimh]

Great debate. It's interesting to note that the same guys that were whipping it up around the pylons later became designers and pilots of our best WWII fighters. It is totally unfair to say the H-1 had no influence on our fighter designs. The prewar fighters were turning speeds the military couldn't touch...that said when it was announced Hughes was going to enter the Cleveland Air Races with the short wing H-1 a huge protest was mounted by other race pilots. Hughes backed out. I really think our Army Air Forces were short-sided in not making this machine into a frontline fighter. We were still transitioning to monoplanes in the late 30's...the H-1 was around in 1935. It's design features are clearly seen in the AM65 and FW 190, wide gear, low profile...etc. The issue of visibility over the nose is really a non-issue, the Corsair has nearly 16ft of nose in front of the cockpit, the Mustang, somewhere around 11ft, they are designed to fly at an angle of attack such that the nose virtually dissappears providing the maximum visibility. The only time its an issue is during takeoff and landing at higher angles of attack. I have yet to fly... or fly in a WWII tailwheel fighter/or trainer that you can see out of with the tail on the ground. Alot of good points are being made here and its fun to watch what could have been!

from a -5 Corsair I got a ride in a couple years ago...visibility is unbelievably good...if you not the artificial horizon we are in a level right turn...no nose!

 

[Waynos]

The fixed cantilever legs won't make any difference.

What makes a difference is the the Gladiator used internally sprung wheels, see:

components company | aircraft components | shock absorber | 1931 | 1207 | Flight Archive

vrs using the side walls of of the tire as the spring/shock absorber mechanism.

Another difference is the higher landing speeds of the H-1 vrs the biplane.

Yes, I was proposing that the internally sprung wheel would mean the H-1 fighter could have used the same legs as the racer , I should have been clearer

 

[Clay_Allison]

Sorry to divert your thread. The V-1710 would have added several hundred pounds to the H-1 and therefore some maneuvering impact. There is no reason to believe that the H-1 could have been built to the weight of the Spitfire. The more slim design could have aided the top speed. If we look at the Vultee Vanguard prototype and the P-66, we could get a glimpse of what performance change could be obtained. The P-66 was designed by the same man who helped Hughes with the H-1 (see tommayer entry above). It was bulkier, however. The Vanguard was the basically the same plane with a streamlined fuselage covering an R-1830, both had the same engine. The top speed of the P-66 was 340 mph and the top speed of the Vanguard was 358 mph. It is apparent that the V-1710 most likely would have improved the H-1 max speed, but it would have had the same altitude problem as the P-39/40.

If a racer/fighter like the Spitfire or Bf-109 had been designed around the Allison V-1710 with the minds and money at the disposal of Howard Hughes, (a man who literally had millions to sink into his personal projects, he could probably have afforded to buy Allison from GM) it's quite possible it would not have had the altitude problems that the P-40 and P-39 had because the existence of a fighter available for order in 1936 that was powered by the Allison V-1710 and could beat the pants off the existing round-engine fighters (P-35, P-36) would drive money and experience into the development of the engine and its supercharging.

The reason the Merlin and the Db-601 jumped ahead of the Allison despite the age of the Allison engine relative to its competitors is arguably due to the lack of orders for engines and planes in the air to provide live feedback. The Hawker Hurricane and the Bf 109 were in the air in 1935, the Spitfire in 1936. There was a production line running for all three before the first P-39 and P-40 prototypes flew.

If we got a production line running for a clean fighter with a V-engine in 1936, maybe exported 10 or so to the Chinese to fly against the IJAF in '37-'38, the development of American engines and airframes would have been lightyears ahead of where it was in 1942.

 

[Shortround6]

The period from 1930 to 1940 probably had more advancement in aircraft and aircraft engines than any other decade.
While money was an issue it couldn't solve everything as some advances depended on other advances being made.
While Howard Hughes did set the speed record in 1935 using 100 octane fuel, this fuel was anything but common at the time and was generally only available in small batches at around $4.00 a gallon. well over 10 times the cost of normal aviation fuels. While experts expected 100 octane fuel to become much more widely available, nobody knew when (as in what year) that would happen. Simply adding enough lead to bring some batches of fuel up to 100 octane resulted in lead fouled spark pugs, misfiring and back fires. At times during the 30s US Army pilots carried cans of lead with them to add to substandard fuel on cross country flights, and this was to get the fuel up to around 87 octane!!
Why Am I going on about the fuel?
Because without high octane (or performance number fuel) there was no need for good superchargers. Poor superchargers would provide all the boost that an engine/fuel combination would tolerate without detonation. Without expensive, laboratory quantities of 100 octane or exotic blends of benzine, alcohol and other things there was no way to test an engine at higher than normal boost pressures. There was certainly no demand for either commercial or military production engines using exotic fuels of uncertain future availability.

In America ALL aircraft superchargers were designed by GE in the first half of the 30s. It was only around 1937 or so that both P&W and Wright started to design their own superchargers. Add Allison to that.
Where would Hughes (even if he wanted to) go for better superchargers in 1935-36-37? One company was designing ALL the superchargers and doing it badly. The real engine manufacturers didn't even have supercharger design departments.

The 109 is a poor comparison because the first hundreds of production planes used the Jumo 210 engine. The DB 601 doesn't show up in it's famous form until late 1938.

Giving 10 planes to the Chinese in 1937-38 wouldn't have shown much at all. Assuming the Chinese didn't crash a fair number of them right away they would have been fighting mostly bi-planes. The Ki-27 "Nate" not being adopted for production until 1937 and probably not showing in up Squadron service in China until much later. Combat debut was in March of 1938. If it did succeed in combat it might have done nothing more than lull the US into thinking all was well.
Certainly all the fighting that was going on in China and to some extent the Spanish Civil war, didn't lead to a very rapid introduction in either armor or self sealing tanks (interest yes, but no production) until late 1939, after WW II had started.

American airframe design was leading the world in the 30s. Many designers and engineers came to the US to study and work for several years before going home (including back to Germany) to put into practice what they had learned.

I don't think the Wright R-2600 or the P&W R-2800 were even a light minute let alone years behind the rest of the world in 1942.

 

[Clay_Allison]

American airframe design was leading the world in the 30s. Many designers and engineers came to the US to study and work for several years before going home (including back to Germany) to put into practice what they had learned.

I don't think the Wright R-2600 or the P&W R-2800 were even a light minute let alone years behind the rest of the world in 1942.

It's a shame we couldn't have a P-47, F4U, or F6F by 1941. Seems like we could have gotten that airframe genius and that engine genius together, perhaps I'll start a new what if about a scaled-up P-36 powered by the R-2800.

In any case, we don't need two-stage supercharging by 1935, just a more mature engine to keep it up with the Merlin in development. You said yourself Allison couldn't really develop much more without orders and money. The (temorarily) hottest fighter in the world would warrant orders for at least 100. Plenty of planes and flights, plenty of money, plenty of motivation to work on getting new dash numbers too keep up with the Spitfire and the 109.

Nothing fuels development like an arms race. A speed-based fighter, rather than a heavy battle wagon like the P-40 I've been trying to fix in my head for months now, would get the race going in the right direction.

 

[gjs238]

Seems like we could have gotten that airframe genius and that engine genius together, perhaps I'll start a new what if about a scaled-up P-36 powered by the R-2800.

Kinda sorta related threads:
- http://www.ww2aircraft.net/forum/aviation/p-36-a-17895.html
- http://www.ww2aircraft.net/forum/aviation/what-if-p-43-r-2600-a-18642.html

 

[Shortround6]

perhaps I'll start a new what if about a scaled-up P-36 powered by the R-2800.

I think it depends on your time line. Since the first R-2800 to fly didn't do so until July 1939, several months after the large order for P-40s is placed it might be a little late to change engines.

And that is in a test hack XA-19.

See the P-60 for a R-2800 powered "P-40".

National Museum of the USAF - Fact Sheet Media

design work on the F4U Corsair is started in the spring of 1938. It doesn't fly until May of 1940.

You might want to think about a "what if" in which the Army orders 2 or 3 P-38 prototypes instead of just one so after the first one crashes the program isn't delayed quite so long.

 

[Clay_Allison]

I think it depends on your time line. Since the first R-2800 to fly didn't do so until July 1939, several months after the large order for P-40s is placed it might be a little late to change engines.

And that is in a test hack XA-19.

See the P-60 for a R-2800 powered "P-40".

National Museum of the USAF - Fact Sheet Media

design work on the F4U Corsair is started in the spring of 1938. It doesn't fly until May of 1940.

You might want to think about a "what if" in which the Army orders 2 or 3 P-38 prototypes instead of just one so after the first one crashes the program isn't delayed quite so long.

That would have been nice. Depending on a two-engine fighter seems weird, but if it had been more reliable because of an undelayed program it would have been awesome.

 

[davparlr]

American airframe design was leading the world in the 30s. Many designers and engineers came to the US to study and work for several years before going home (including back to Germany) to put into practice what they had learned.

I don't think the Wright R-2600 or the P&W R-2800 were even a light minute let alone years behind the rest of the world in 1942.

I would certainly agree with this. America had exceptionally talented designers in Douglas, Lockheed Bros. and Jack Northrop and others. The Lockheed's Vega and the Northrop Gamma certainly advanced performance and design, as did the Hughes H-1. The De Havilland is well known for winning the MacRobertson Air Race of 1934 with the special designed DH.88 Comet, but more significantly, the second and third places were won by American commercial aircraft, the KLM DC-2 and Roscoe Turner's Boeing 247D, An accomplishment that stunned the world of airplane travel.

Wright and Pratt and Whitney were cutting edge engine designers in the radial field in the 30's. Both engines would have been available by the end of 1939.

It's a shame we couldn't have a P-47, F4U, or F6F by 1941. Seems like we could have gotten that airframe genius and that engine genius together, perhaps I'll start a new what if about a scaled-up P-36 powered by the R-2800.

In any case, we don't need two-stage supercharging by 1935, just a more mature engine to keep it up with the Merlin in development. You said yourself Allison couldn't really develop much more without orders and money. The (temorarily) hottest fighter in the world would warrant orders for at least 100. Plenty of planes and flights, plenty of money, plenty of motivation to work on getting new dash numbers too keep up with the Spitfire and the 109.

Nothing fuels development like an arms race. A speed-based fighter, rather than a heavy battle wagon like the P-40 I've been trying to fix in my head for months now, would get the race going in the right direction.

Technology was certainly there, but desirability seems to be lacking, possibly justified. The US military just wasn't interested in point defense fighters like the Spitfire and Bf-109. Unfortunately, US advanced design got bogged down in complex designs. The AAF was developing the complex, turbo-charged aircraft, the P-38 and P-47, and the Navy was developing the complex, and struggling, F4U. Interesting enough, Grumman didn't seem to pursue the R-2800 engine installation until late, possibly because of manufacturing of the F4F. Had the AAF urged Curtis, Republic, and Vultee to push forward on designing to the non-turbocharged R-2800, it is likely that the USAAF would have had a powerful fighter at Pearl Harbor, if they got up. Could you imagine the havoc the AVG could have done to the Japanese if they had R-2800 powered versions of the P-43s or P-66s? Of course they would have had to been expedited!

Maybe renrich has it right. If the AAF had joined with the Navy and developed a land based version of the F4U (maybe by Vultee) with no folding wings, maybe straight wings, no slow speed carrier landings, simple landing gear, therefore much simpler (less problems) and lighter, maybe it could have been developed as R-2800 fighter in time to start the war. First flight May, 1940, operational March, 1941, deployed June 1941. That would do the trick. Guadalcanal would have been a whole lot less problematic.

 

[Shortround6]

I would certainly agree with this. America had exceptionally talented designers in Douglas, Lockheed Bros. and Jack Northrop and others. The Lockheed's Vega and the Northrop Gamma certainly advanced performance and design, as did the Hughes H-1. The De Havilland is well known for winning the MacRobertson Air Race of 1934 with the special designed DH.88 Comet, but more significantly, the second and third places were won by American commercial aircraft, the KLM DC-2 and Roscoe Turner's Boeing 247D, An accomplishment that stunned the world of airplane travel.

Wright and Pratt and Whitney were cutting edge engine designers in the radial field in the 30's. Both engines would have been available by the end of 1939.

All quite true except the last sentence. The R-2800 wasn't ready/available in 1939. it was 1941 before it was available in any numbers and that was the "A" version, most of which went into B-26 bombers and was rated at 1850HP. With Ford given 14.3 million of government money in Sept of 1940 for a second production line it wasn't because of lack of orders or demand.


Grumman had proposed a R-2600 powered development of the Wildcat but the Navy wasn't interested. This is not quite the same as the F6F-1 which was powered by the R-2600 Second prototype changed to the R-2800.

Maybe renrich has it right. If the AAF had joined with the Navy and developed a land based version of the F4U (maybe by Vultee) with no folding wings, maybe straight wings, no slow speed carrier landings, simple landing gear, therefore much simpler (less problems) and lighter, maybe it could have been developed as R-2800 fighter in time to start the war..

Corsair was designed the way it was for a number of reasons. the Gull wing met the wing met the fuselage at a 90 degree angle. This provided for the least amount of interference drag. No wing root fillets were needed. The simple landing gear wasn't so simple with that big engine. with size propellers needed landing gear was either very long or rather tricky. Please remember that the P-47 landing rear was 9in shorter retracted than when lowered in order to have enough room for the guns/ammo.

R-2800s came in a variety of flavors.

Single stage single speed superchargers.
Single stage single speed superchargers + turbo.
Single stage two speed superchargers.
Two stage superchargers with a single speed engine supercharger and a neutral, low and high auxiliary stage.

The Early R-2800s as used in the B-26 bombers were the single stage two speed type and were good for 1850 hp for take off and 1500hp at 14,000ft military power.
While planes powered by such an engine would show better performance than some of the planes historically used it would not be by anywhere near the difference in performance exhibited by later planes using "B" series engines and more complicated superchargers.

 

[davparlr]

Corsair was designed the way it was for a number of reasons. the Gull wing met the wing met the fuselage at a 90 degree angle. This provided for the least amount of interference drag. No wing root fillets were needed. The simple landing gear wasn't so simple with that big engine. with size propellers needed landing gear was either very long or rather tricky. Please remember that the P-47 landing rear was 9in shorter retracted than when lowered in order to have enough room for the guns/ammo.

Most of the problems with the delay of the F4U were in dealing with the Naval requirements. There are several reasons for the gull wing. The one that seems most reasonable was because of the requirement for wing fold. This would have required the long landing gear to retract rearward ala F6F. However the wing chord was too small for this to occur therefore, the gull wing to shorten gear. The P-47 had a complex gear due to its mid-wing configuration which required the gear to retract into the wing. Had the Army been doing a parallel development of the F4U, no fold was required, so the wing could be straight and the gear could retract into the fuselage ala P-51 or Sea Fury (I had to attach a beautiful picture of the Sea Fury). It is interesting that the Sea Fury solved all of these problems. Anyway, the cheaper and lighter straight wing would have more than made up for a wing root fillet, since no other aircraft used the gull except the Ju-87. In addition, other issues the Navy version had to address which, would have been simpler for the Army, included low speed handling, visibility, and stall characteristics. So, in my opinion, if there had been parallel development of a Navy F4U and an Army F4U, production of an Army version would have occurred much earlier, maybe by Spring/Summer, 1941.

More realistically, if the Army had taken the Navy F4U prototype in May of 1940, and just requested fixed wings, it could possibly have fielded a fighter in the summer of 1941, just by not having to fix all the naval issues. It would have been a great stop gap until the high altitude P-47 and P-51 came along.

This is all hypothetical, of course.

http://www.biocrawler.com/w/images/0/0f/Hawker_Sea_Fury-01.JPG

 

[Shortround6]

The clearance for the large propeller combined with the short sturdy landing gear seems to be the most popular story.
The low hinge point for the folding wing certainly doesn't hurt and perhaps was adopted to avoid patent disputes with Grumman?
The first prototype had folding wings so the fitting of the folding wings shouldn't have delayed the project.

The Corsair used a multi-spar center section using ( I believe?) forgings. "JUST" sticking on a straight wing means designing a whole new wing and landing gear which might delay things by how many months compared to bolting on the existing outer wings and just leaving out the hinge parts?

The Fury certainly is a great airplane but it is also at least 4 years latter in timing if not maybe 6 years and a lot was learned in the mean time. As a for instance some Fury's used 5 bladed props. Who was using a 4 blade when the Corsair was first designed? A four blade constant speed prop?

You are not addressing the question which version of the R-2800 would be available for this project and when.

While several experimental "A" series engines of 1800-1850hp with 2 stage superchargers were fitted to the prototype Corsair the Production 2000hp "B" series with 2 stage superchargers don't START to be delivered until Nov 1941. The vast bulk of R-2800s delivered in 1941 (all 1733 of them) were 1850 HP single stage "A" series engines, most of which went to B-26 bombers.

See this page for performance of the prototype with early 2 stage supercharger.

xf4u-1spec

 

[davparlr]

The clearance for the large propeller combined with the short sturdy landing gear seems to be the most popular story.

Short, sturdy landing gear may have been the choice for Vought, but Grumman, with the later TBM and F6F didn't seem to have problems with long landing gear.

The low hinge point for the folding wing certainly doesn't hurt and perhaps was adopted to avoid patent disputes with Grumman?
The first prototype had folding wings so the fitting of the folding wings shouldn't have delayed the project.

I don't think the wing design added much delay to the project, although the shear complexity of such a design, including a complex gear and gear door design, would have some impact. I think most of the delay came post design and prototype flight with modifications required to adapt to Naval operations.

The Corsair used a multi-spar center section using ( I believe?) forgings. "JUST" sticking on a straight wing means designing a whole new wing and landing gear which might delay things by how many months compared to bolting on the existing outer wings and just leaving out the hinge parts?

To implement the plan I stated, the Army would have had to parallel develop a land base version like the present F-35 program, which is a totally unrealistic assertion for the time. This plan would just optimize the cost and performance for the Army, not necessarily add to an earlier operation. The big impact of the folding gull wing design would be in weight and cost.

The Fury certainly is a great airplane but it is also at least 4 years latter in timing if not maybe 6 years and a lot was learned in the mean time. As a for instance some Fury's used 5 bladed props. Who was using a 4 blade when the Corsair was first designed? A four blade constant speed prop?

True, but it does show that a straight wing would allow a much simpler landing gear design. Even the 5 blade prop is only about 3.5 inches less radius than the F4U's. Isn't that picture beautiful? I saw one of these flying at the Chino airport, along with a bunch of other aircraft including the F8F. It was very impressive, as was the F8F.

You are not addressing the question which version of the R-2800 would be available for this project and when.

While several experimental "A" series engines of 1800-1850hp with 2 stage superchargers were fitted to the prototype Corsair the Production 2000hp "B" series with 2 stage superchargers don't START to be delivered until Nov 1941. The vast bulk of R-2800s delivered in 1941 (all 1733 of them) were 1850 HP single stage "A" series engines, most of which went to B-26 bombers.

See this page for performance of the prototype with early 2 stage supercharger.

xf4u-1spec

I'm not particularly knowledgeable about engines or production numbers, however, if an F4U had been available in PTO by Guadalcanal, even with the earlier engines, I think it would have made a major impact. It still would have been over 60 mph faster than the Zero, an overpowering capability. In Europe, it would have needed a later engine to compete with the Fw-109A.

As for the performance of the prototype, if it could do 405 mph at sea level, buy it!