Wildcat during the Battle of Britain

[slaterat]

The F4F-3 with the 2 stage P&W was faster over the entire altitude range and climbed better than the BoB Hurricane with a constant speed prop according to tests. US Navy pilots at Coral Sea thought they gave up nothing in speed and climb to a Zero but were far less maneuverable. The F4F-4 was an overweight pig and the Martlet with a single stage engine would run out of breath at higher altitudes but the early F4F-3 performed well, Eric Brown called its initial climb rate of 3,300 fpm "sensational".

1.You need to read that whole report. The engine conked out after the speed tests and had to be replaced for the climbing tests. Might not have been in the best shape.

2 The revised PEC boosts the Hurricanes speed a bit, up to 324 mph.

http://www.wwiiaircraftperformance.org/hurricane/hurricane-I-raechart.jpg

3 That test was flown at 6.25 lbs boost. The Hurricane Mk 1 was cleared for 12 lbs in the spring of 1940. That gives the Hurri Mk 1, 325 mph from 10 k to 18k

http://www.wwiiaircraftperformance.org/hurricane/hurricane-I-level.jpg

Once you add some armor and self sealing tanks to the Wildcat the climb rate goes down.

 

[stona]

No more than the Spitfire and Bf109 were on grass fields.

Whether the F4F's undercarriage would be a problem operating from grass can't be said for sure, unless someone did some trials. What can be said is that the track at 6' 5" is almost identical to a Bf 109 (2062mm) and Spitfire (can't find the figure, but it was slightly narrower than the Bf 109). Unlike the other two the F4F was designed for the forces involved in carrier landing, particularly sideways forces which the other two could not tolerate. Despite that fact that the F4F's ground handling was often described as 'tricky' and that the struts were prone to collapse (in deck landings), I doubt that it would be a problem. The F4F also had a tailwheel lock.

The issue of the Bf 109 was nothing to do with its track, but its geometry. Both the Bf 109 and Spitfire were designed to operate from grass aerodromes and problems arose, or were exacerbated, when they had to operate from made runways. Neither started life with a tailwheel lock.

 

[pinsog]

1.You need to read that whole report. The engine conked out after the speed tests and had to be replaced for the climbing tests. Might not have been in the best shape.

2 The revised PEC boosts the Hurricanes speed a bit, up to 324 mph.

http://www.wwiiaircraftperformance.org/hurricane/hurricane-I-raechart.jpg

3 That test was flown at 6.25 lbs boost. The Hurricane Mk 1 was cleared for 12 lbs in the spring of 1940. That gives the Hurri Mk 1, 325 mph from 10 k to 18k

http://www.wwiiaircraftperformance.org/hurricane/hurricane-I-level.jpg

Once you add some armor and self sealing tanks to the Wildcat the climb rate goes down.

ThIs is from the test I posted, notice the Wildcat had armor plate (155 pounds) full fuel and oil protection and still does 336 mph at 22,000 feet. That would have been extremely competitive in the BoB. 109's trying to bunt (shove stick forward and diving away) wouldn't work on a Wildcat. That would be a nasty surprise for a German pilot used to doing that to Spitfires and Hurricanes.

 

[PAT303]

If your 1941 era Wildcat was available in 1939 and squadron service aircraft hit those numbers you still have the issue posted back on page 1 reply no. 14, the guns didn't work and neither did the ammunition.

 

[P-39 Expert]

View attachment 593724ThIs is from the test I posted, notice the Wildcat had armor plate (155 pounds) full fuel and oil protection and still does 336 mph at 22,000 feet. That would have been extremely competitive in the BoB. 109's trying to bunt (shove stick forward and diving away) wouldn't work on a Wildcat. That would be a nasty surprise for a German pilot used to doing that to Spitfires and Hurricanes.

That may be from the specifications, and not from an actual test.

 

[Mad Dog]

So, if you were planning on defending your country against attack and you had F4Fs, would you just leave them on the ground and just give up? No! You'd use them and the most sensible way of doing that would be getting them in a situation where their assets could be put to use. The RAF had Gladiators, Defiants and Blenheims tackling the Luftwaffe. They used whatever they could to defend the country. The Royal Navy used the Roc! If the Wildcats were there, they'd use them and find an advantage.

Yes, but the Gladiator actually had a much better rate of climb than the Hurricane, making it at least a viable interceptor away from the ME109s.

 

[Mad Dog]

....The Japanese army, not wanting to rely on the IJN decided to make their own IJA escort carriers, focused on ASW. Imagine the British army deciding to do the same. Similar the the IJA carrier's Kokusai Ki-76, the British Army Air Corp operated the Taylorcraft Auster. Of course, like the Martlet in the Battle of Britain, we must fiddle with the timeline as both the Army Air Corp and the Auster did not exist until 1942.....]

IIRC, de Havilland offered the Leopard Moth as a STOL ASW aircraft to operate from MACs, but the Admiralty decided the really pressing need was fighters (Hurricanes) to take on the FW200s.

 

[Mad Dog]

If not the Wildcat, what US aircraft would Britain welcome in the BoB? Curtiss P-40?

Well, only the Curtiss P-36 would be available in any numbers (provided the French and US were persuaded to let the RAF grab an order), or the Seversky P-35. You could have got the first turbocharged Republic P-43s by September 1940, but those were without armour or self-sealing tanks, and whilst they had good altitude performance the rate of climb and firepower were not exactly sparkling. The unarmoured P-35 would not have stood the comparison with the Hurri I, but the P-36 might have done well.
The P-36 was already proven in France, and the RAF actually thought quite highly of the Hawk 75-A2 they tested against a Spitfire. The A3 version had reasonable altitude performance and was fast enough to catch the German bombers, and could be armed with six .303s quite easily. The A4 was faster still but had the troublesome Cyclone engine. The P-36 also offered an advantage in that escaping French pilots with Hawk 75 experience could be given P-36s and be operational almost immediately, boosting the number of pilots available.
But by the time the Brits got the French order the Battle was over, and it was decided to send them overseas where their air-cooled engines were a distinct advantage. They provided sterling service for the SAAF in East Africa and the RAF in Burma, being used up to 1943 in the latter theatre. IHO, had there not been enough Hurricanes and Spitfires, the next best available choice would have been the Curtiss P-36.

 

[pinehilljoe]

The Wildcat had a fairly robust maingear, so a grass field shouldn't be an issue.

The F4Fs did we'll operating from Henderson Field

thanks for the posts to date. When you post a question you get broad answers, another reason I like this forum.

 

[pinsog]

That may be from the specifications, and not from an actual test.

http://www.wwiiaircraftperformance.org/f4f/f4f-3-detail-specification.pdf

This is the full report showing the specs of the actual F4F-3 used in the test. It was armed, armored and had self sealing tanks

 

[Shortround6]

What is posted is

The French H81A-1s were fitted with the V-1710-C15 engine (aka V-1710-33). I believe the ex-French AC that were taken over by the RAF were known as the Tomahawk I. Tomahawk I pilot's notes still listed the same engine.

Allison was having trouble getting the V-1710-33 through the 150 hour type test, I think it took a total of 5 engines and some redesign of the test stand (different motor mounts for one thing). However such was the urgency of the time that Allison was allowed to produce and deliver engines with the understanding that all engines (at least US ones) would be brought up to the "final" standard of the engine that passed the 150hr test at Allison's expense. I believe that up to 228 engines were affected.

There was no change in designation for these early engines. The early test stand engine mount was too rigid and some of the engines failed due to fatigue cracks. There were also some other problems in early service use. Allison did get the engine sorted out, all 228 engines were "modernized" and brought up to the final configuration (which included a stronger crankcase).
What is unknown is if any of the "commercial" (French/British engines) built in the summer of 1940 had any of the older parts (unmodernized) and if the British simply ran them at full power anyway and accepted shorter service life. The British did use the increased valve clearance which helped considerably with the backfire problems. There were some other problems that continued into and through 1941. for example The British fitted larger generators than the US did and in service the generator drive mechanism tended to fail under the greater load.
The AVG was supposed to get a batch of uprated generator drives for example but it is unknown if they actually received them.

 

[Shortround6]

http://www.wwiiaircraftperformance.org/f4f/f4f-3-detail-specification.pdf

This is the full report showing the specs of the actual F4F-3 used in the test. It was armed, armored and had self sealing tanks

and on page 5 at the top line 113A it says.

"The performance is estimated to be as follows"

Bolding by me.

I am also wondering (unless it is a typo) how the overloaded fighter (3rd column) is 10mph faster than than "normal" fighter at 22,000ft when it was 2mph slower at 19,000ft.

and was 537lbs heavier. (full fuel tanks/oil and ammo)

 

[pinsog]

If your 1941 era Wildcat was available in 1939 and squadron service aircraft hit those numbers you still have the issue posted back on page 1 reply no. 14, the guns didn't work and neither did the ammunition.

I didn't start the thread, but IF the F4F-3 was ready in squadron numbers for the BoB I would probably request that Grumman fix the guns before delivery. I'm a practical guy that way. OR the British could have requested 8 303's be mounted instead, which would save a couple hundred pounds in weight meaning it climbed even better.
"The ammo didn't work"? I'm aware that a 2500 FPS ball ammo 50 round isn't as good as a 2900 FPS armor piercing incendiary round, I would like to point out that when a 2500 FPS 800 grain bullet hits an aircraft wing, starts tumbling and strikes the fuel tank sideways it is going to leave a 1/2 inch by 3 inch hole and will also exit out the other side. If the tank is anywhere near full it will probably burst at the seams. While setting an aircraft on fire is obviously preferable, bursting the fuel tank so the poor guy runs out of fuel ends up in the channel seems like a good result as well.
If we remove the tail hook and flotation equipment we save 50 pounds. If we replace the 4 50's with 8 303's then we save another 250 pounds or so. 300 pounds total weight savings would be a pretty serious upgrade in performance as far as climb.

 

[pinsog]

and on page 5 at the top line 113A it says.

"The performance is estimated to be as follows"

Bolding by me.

I am also wondering (unless it is a typo) how the overloaded fighter (3rd column) is 10mph faster than than "normal" fighter at 22,000ft when it was 2mph slower at 19,000ft.

and was 537lbs heavier. (full fuel tanks/oil and ammo)

Interesting. I had already figured the lower speed for the lighter plane was a typo.

 

[Shortround6]

Interesting. I had already figured the lower speed for the lighter plane was a typo.

Except that the heavier plane is 1-2mph slower at all listed lower altitudes.

Please see the test above this report on the site which gives actual test results from 4 different aircraft including No 1848.
Top speed was 331mph after taking off at 7300lbs. how much fuel was burned getting to 21,000ft?

I would also note that as of Dec 1940 there were only about 22 F4F-3s built. There seems to have been a shortage of engines, otherwise why would the US Navy (and Marines) accept 65 F4F-3A with single stage superchargers in 1941? BTW this was the engine used in the Martlet II. 1000hp at 14,500ft in high gear. British data sheet claims 317mph at 14,000ft.

You need a considerable time shift to get F4F-3s with two stage engines in numbers for the BoB. You need 3-6 months just to get a few squadrons of Martlet Is and IIs.

 

[pinsog]

Except that the heavier plane is 1-2mph slower at all listed lower altitudes.

Please see the test above this report on the site which gives actual test results from 4 different aircraft including No 1848.
Top speed was 331mph after taking off at 7300lbs. how much fuel was burned getting to 21,000ft?

I would also note that as of Dec 1940 there were only about 22 F4F-3s built. There seems to have been a shortage of engines, otherwise why would the US Navy (and Marines) accept 65 F4F-3A with single stage superchargers in 1941? BTW this was the engine used in the Martlet II. 1000hp at 14,500ft in high gear. British data sheet claims 317mph at 14,000ft.

You need a considerable time shift to get F4F-3s with two stage engines in numbers for the BoB. You need 3-6 months just to get a few squadrons of Martlet Is and IIs.

The original thread starter says he understands the Wildcat was a year too late for the BoB but how would it have done if it was there. I agree 100% that the Wildcat wasn't going to make the BoB as well. I also know of the engine shortage and why they used the single stage engines. If we are going to assume it was there for the battle we can assume it had the 2 stage engine it was designed for in the first place. I'm fine with 331 mph as the top speed from a different test as well.

 

[GrauGeist]

The Wildcat wasn't a year too late, it was active as the Martlet (French G-36A) during the end of the BoB, assigned to FAA's No. 804 Squadron based at RNAS Skaebrae.

They received the G-36As in October, but that is still within the recognized time period of the battle.

 

[nuuumannn]

But by the time the Brits got the French order the Battle was over, and it was decided to send them overseas where their air-cooled engines were a distinct advantage.

The RAF received the first ex-Armee de l'Air Hawk 75s in July 1940, while the battle was raging. The reason behind them not being used is they were delivered to Maintenance Units for the fitting of British equipment and the reversing of the throttle arrangement - the French, for reasons only known to themselves did not operate their power levers in the traditional 'Balls-to-the-wall" fashion, pulling the lever toward the pilot to increase power and so forth. The completed examples were kept in reserve but none took part in any operations -after trials by the They were shipped to North Africa in early 1941.

Trials with the A & AEE revealed that the Hawk 75 was nice to fly with docile stall characteristics and more manoeuvrable than the Spitfire and Hurricane but could not match the latter's performance. Following these trials, no effort was made to induct them following modifications into home based RAF units.

Unlike the Martlets that were originally from the French order on the Grumman production line and modified by the manufacturer to British specs, including two .50 cal machine guns in each wing, also changing the direction of the throttles (!) , the first arriving with Scottish Aviation at Prestwick in August 1940 and the last of the first order toward the end of September. The next batch were sunk aboard the freighter SS Ruperra.

The first French example (G.36A, which became Martlet I) made its first flight on 10 May 1940, the day of the invasion and the French and British Purchasing Commissions worked fast to get Grumman to convert the order to British hands.

 

[PAT303]

I didn't start the thread, but IF the F4F-3 was ready in squadron numbers for the BoB I would probably request that Grumman fix the guns before delivery. I'm a practical guy that way.

Curtis couldn't get them to work in the P40 and North American couldn't get them to work in the P51 as late as 1943 yet Grumman would have them sorted in 1940 loaded with tracer and API that took until 1942 and 1944 to develop?.

 

[pinsog]

Curtis couldn't get them to work in the P40 and North American couldn't get them to work in the P51 as late as 1943 yet Grumman would have them sorted in 1940 loaded with tracer and API that took until 1942 and 1944 to develop?.

Did you read what I typed? I said make Grumman fix the guns OR replace them with 8 303's.

I also said. " I'm aware that a 2500 FPS ball ammo 50 round isn't as good as a 2900 FPS armor piercing incendiary round, I would like to point out that when a 2500 FPS 800 grain bullet hits an aircraft wing, starts tumbling and strikes the fuel tank sideways it is going to leave a 1/2 inch by 3 inch hole and will also exit out the other side. If the tank is anywhere near full it will probably burst at the seams. While setting an aircraft on fire is obviously preferable, bursting the fuel tank so the poor guy runs out of fuel ends up in the channel seems like a good result as well."

I said nothing about invention 50 API Incendiary bullets 2-3 years earlier. While far from perfect, I can assure you that a 750-800 grain 50 caliber ball round at 2500 FPS will do a lot of damage to fuel tanks, engines and pilots.