Was single seat Firefly possible?

[Zipper730]

1) We know that the RAF refused to let the Sabre go to the FAA and the two speed Merlins were in high demand by the RAF.

When was these decisions made? I figure the twin-speed superchargers appeared in 1940-1941?

That said, I don't recall two-speed merlins (single-stage) used on early Spitfires. The Hurricane Mk.II's used them

2) Sorry, I meant single seat fighters. The FAA was using the Gloster Sea Gladiator from 1938. Look at the USN/F4F-4 issues at Midway when the ZB failed.

I actually never heard of that particular issue, but I believe you. There's a lot of stuff that don't appear in the history books.

3) The FAA tested both the Martlet II and IV and both had a maximum speed of under 300mph

Really, that's lower than I would have thought. From what I remember, the Martlet's had a single-stage, twin-speed supercharger. I thought they could at least muster low 310-320 mph.

at low altitude the Martlet II was barely faster than a Fulmar II using 12lb boost.

What boost settings were the Martlet II using?

4) Changing the Firefly radiator design from the chin to wing mounted, seems to have resulted in a 20-30mph speed gain. We can see that the Firebrand was initially much slower than predicted. I think there was a general underestimation of high speed drag effects.

So this was a problem seen in much of the British government? That said, I'm curious if the chin radiator was simply redesigned -- what could you squeeze out?

5) The RAF had an abundance of TE aircraft for overwater recon and could use specially modified SE aircraft for overland recon because the pilot could navigate visually using terrain recognition.

That's how they overcame the problem, by relying on land based aircraft?

Because some bright person figured it could be made to fit the Spitfire.

It was about the same size as the Griffon, though I was told it wasn't as good.

The Firefly also went from a single stage two speed supercharger on the I to a two stage two speed supercharger ob the IV (with leading edge radiators).

 

[pinsog]

Wildcat/Martlet

Top speeds are 313, 317, 300, 307, 298 mph

 

[RCAFson]

Wildcat/Martlet
View attachment 569523View attachment 569524View attachment 569525View attachment 569526View attachment 569527
Top speeds are 313, 317, 300, 307, 298 mph

These cards illustrate the number of misconceptions that have arisen regarding the Martlet II and IV. Most of the aircraft cards shown are for mainly non-operational types that saw little or no combat, because of engine problems and/or fixed wings, lack of armour and SS tanks.

Card 124 and 126 (look at the weight and fuel capacity) are for early fixed wing aircraft with no armour and no SS tanks, with the Martlet 1 (card 124) being the Martlet aircraft referred to by Crossley. Martlet 2 (card 126) states, incorrectly, that it has folding wings as the weight is wrong and it does not give the folded wing dimensions.

Wildcat II (card 176) is a Martlet II = 292 mph at 6000ft and 300 at 14000ft

The Wildcat IV F4F4B (card 178) is a Martlet IV = 286mph at 4000ft and 298mph at 15000ft

The above two types were the main types used operationally by the FAA


Actual performance in RAE trials for the Martlet II, Martlet IV and Fulmar II was:

Martlet II = 293 at 5400ft and 293mph at 13800ft. (only 90 were ever delivered to the FAA) (Flying to the limit)

Martlet IV = 278mph at 3400ft and 298 at 14600ft, both at 45in boost. (RAE Test report)

Fulmar II at ~12lb boost was 268 mph at 6800ft. (RAE Test report) In Jan 1942 the Merlin 30 was uprated to 16lb boost.

 

[Kevin J]

These cards illustrate the number of misconceptions that have arisen regarding the Martlet II and IV. Most of the aircraft cards shown are for mainly non-operational types that saw little or no combat, because of engine problems and/or fixed wings, lack of armour and SS tanks.

Card 124 and 126 (look at the weight and fuel capacity) are for early fixed wing aircraft with no armour and no SS tanks, with the Martlet 1 (card 124) being the Martlet aircraft referred to by Crossley. Martlet 2 (card 126) states, incorrectly, that it has folding wings as the weight is wrong and it does not give the folded wing dimensions.

Wildcat II (card 176) is a Martlet II = 292 mph at 6000ft and 300 at 14000ft

The Wildcat IV F4F4B (card 178) is a Martlet IV = 286mph at 4000ft and 298mph at 15000ft

The above two types were the main types used operationally by the FAA


Actual performance in RAE trials for the Martlet II, Martlet IV and Fulmar II was:

Martlet II = 293 at 5400ft and 293mph at 13800ft. (only 90 were ever delivered to the FAA) (Flying to the limit)

Martlet IV = 278mph at 3400ft and 298 at 14600ft, both at 45in boost. (RAE Test report)

Fulmar II at ~12lb boost was 268 mph at 6800ft. (RAE Test report) In Jan 1942 the Merlin 30 was uprated to 16lb boost.

Card 124 Martlet I operational late 1940 from land bases. Some operated off Illustrious according to Wikipedia.
I'd be surprised if no SS fuel tanks nor armour was fitted was fitted to any of these fighters as this is post Bob.
Card 126 Martlet II. Fixed wings. We're these the Martlet IIs operated off Audacity.
Card 176 Wildcat II. Folding wings. 36 retained in UK and 54 sent to Far East. Operational from carriers.
Card 177 Wildcat III. No naval features. Operated in Western Desert.
Card 178 Wildcat IV. Folding wings. Carrier ops.
RAE accepted +-3% deviation from manufacturing guidelines. So +-10 mph is both acceptable and feasible.

 

[Kevin J]

Card 124 Martlet I operational late 1940 from land bases. Some operated off Illustrious according to Wikipedia.
I'd be surprised if no SS fuel tanks nor armour was fitted to any of these fighters as this is post BoB.
Card 126 Martlet II. Fixed wings. We're these the Martlet IIs operated off Audacity.
Card 176 Wildcat II. Folding wings. 36 retained in UK and 54 sent to Far East. Operational from carriers.
Card 177 Wildcat III. No naval features. Operated in Western Desert.
Card 178 Wildcat IV. Folding wings. Carrier ops.
RAE accepted +-3% deviation from manufacturing guidelines. So +-10 mph is both acceptable and feasible.

In 1945, Luftwaffe allowed +-5% deviation, so Me 262 may do anything from 485 to 540 mph and be deemed acceptable.

 

[pinsog]

I think a fully developed F5F would be the best choice as well. The prototype with radio and ballasted for weapons would do:
312 mph at SL on 2,000 hp
326 mph at 4500 ft on 2,000 hp
324 mph at 7300 ft on 1,800 hp
346 mph at 14,000 ft on 1,800 hp
352 mph at 20,000 ft on 1500 hp

With uprated Wright's from a Wildcat
331 mph at SL on 2400 hp
346 mph at 4500 ft on 2400 hp
335 mph at 7300 ft on 2000 hp
358 mph at 14,000 ft on 2000 hp
364 mph at 20,000 ft

With 2 stage P&W (not including 7 square feet less frontal area on the engines)
331 mph at SL on 2400 hp
346 mph at 4500 ft on 2400 hp
346 mph at 7300 ft on 2200 hp
358 mph at 14000 ft on 2000 hp
387 mph at 20,000 ft on 2000 hp

Same wing area as a Corsair with 4-600 more hp at take off. Add dive brakes and you have an airplane that can be a fighter, dive bomber or carry a torpedo. If the F5F is built INSTEAD of the Wildcat, it is in action by the end of 1940. It is the only aircraft the Royal Navy needs.

 

[pinsog]

Then you get into what other modifications do you want.
Go ahead and fold the wings like a Wildcat and Hellcat so there are no clearance issues in the hanger.

Do you want to add a 2nd seat and long range radio for a navigator/observer?
Do you want to add a 75 gallon tank in each outer wing to bring total internal fuel up to 400 gallons? (Self sealing tank reduces original 279 gallons down to 250 gallons, same as Hellcat)
Do you want to add a bit of wingspan to increase load carrying ability or decrease landing speed?

All of these things should be possible and not detract too much from performance since you have plenty of power to offset weight gain. Besides, the Royal Navy wasn't fighting Zeros anyway. Most of the time they were attacking unescorted JU87, JU88 and Italian torpedo bombers, so a little performance loss won't hurt them as they would have had it to spare.

 

[Kevin J]

I think a fully developed F5F would be the best choice as well. The prototype with radio and ballasted for weapons would do:
312 mph at SL on 2,000 hp
326 mph at 4500 ft on 2,000 hp
324 mph at 7300 ft on 1,800 hp
346 mph at 14,000 ft on 1,800 hp
352 mph at 20,000 ft on 1500 hp

With uprated Wright's from a Wildcat
331 mph at SL on 2400 hp
346 mph at 4500 ft on 2400 hp
335 mph at 7300 ft on 2000 hp
358 mph at 14,000 ft on 2000 hp
364 mph at 20,000 ft

With 2 stage P&W (not including 7 square feet less frontal area on the engines)
331 mph at SL on 2400 hp
346 mph at 4500 ft on 2400 hp
346 mph at 7300 ft on 2200 hp
358 mph at 14000 ft on 2000 hp
387 mph at 20,000 ft on 2000 hp

Same wing area as a Corsair with 4-600 more hp at take off. Add dive brakes and you have an airplane that can be a fighter, dive bomber or carry a torpedo. If the F5F is built INSTEAD of the Wildcat, it is in action by the end of 1940. It is the only aircraft the Royal Navy needs.

Maybe a Sea Whirlwind could be in service by that time, I'm not convinced the F5F could be. I like the idea of the RR Vulture powered Fulmar too. If you can fit a Vulture in a Henley then why not a Fulmar.

 

[Kevin J]

I think a fully developed F5F would be the best choice as well. The prototype with radio and ballasted for weapons would do:
312 mph at SL on 2,000 hp
326 mph at 4500 ft on 2,000 hp
324 mph at 7300 ft on 1,800 hp
346 mph at 14,000 ft on 1,800 hp
352 mph at 20,000 ft on 1500 hp

With uprated Wright's from a Wildcat
331 mph at SL on 2400 hp
346 mph at 4500 ft on 2400 hp
335 mph at 7300 ft on 2000 hp
358 mph at 14,000 ft on 2000 hp
364 mph at 20,000 ft

With 2 stage P&W (not including 7 square feet less frontal area on the engines)
331 mph at SL on 2400 hp
346 mph at 4500 ft on 2400 hp
346 mph at 7300 ft on 2200 hp
358 mph at 14000 ft on 2000 hp
387 mph at 20,000 ft on 2000 hp

Same wing area as a Corsair with 4-600 more hp at take off. Add dive brakes and you have an airplane that can be a fighter, dive bomber or carry a torpedo. If the F5F is built INSTEAD of the Wildcat, it is in action by the end of 1940. It is the only aircraft the Royal Navy needs.

Maybe a Sea Whirlwind could be in service by that time, I'm not convinced the F5F could be. I like the idea of the RR Vulture powered Fulmar too. If you can fit a Vulture in a Henley then why not a Fulmar.

 

[pinsog]

Maybe a Sea Whirlwind could be in service by that time, I'm not convinced the F5F could be. I like the idea of the RR Vulture powered Fulmar too. If you can fit a Vulture in a Henley then why not a Fulmar.

I like the Whirlwind, but I don't think it could operate from a carrier. Seems like it stalled in the mid to upper 90's.

I think, personally, the only thing that made the F5F take so long was they simply weren't working on it. They were working on the Wildcat because it was very close to a sure thing. The F5F could have been ordered into production much earlier and modified along the way. The prototype was literally a twin engine Wildcat until they rebuilt the fuselage without the high back behind the pilot

 

[Kevin J]

I like the Whirlwind, but I don't think it could operate from a carrier. Seems like it stalled in the mid to upper 90's.

I think, personally, the only thing that made the F5F take so long was they simply weren't working on it. They were working on the Wildcat because it was very close to a sure thing. The F5F could have been ordered into production much earlier and modified along the way. The prototype was literally a twin engine Wildcat until they rebuilt the fuselage without the high back behind the pilot

Building the P-50 took up valuable time. Getting the F5F into service mid 1942 for the FAA looks more than feasible and its a much better plane than the Wildcat. You'd still need the latter for the jeep carriers.

 

[pinsog]

That's about as Wildcat as it gets. Then they rebuilt it with the bubble canopy for increased visibility and I assume, less weight.

 

[pinsog]

If you have 50 of these aboard Ark Royal:
Then you have 50 fighters to repel an attack.
You have 50 long range scouts to search for the Bismarck.
You have 50 dive bombers to bomb Bismarck that are capable of carrying a VERY heavy bomb load.
You also have 50 torpedo bombers

 

[pinsog]

Building the P-50 took up valuable time. Getting the F5F into service mid 1942 for the FAA looks more than feasible and its a much better plane than the Wildcat. You'd still need the latter for the jeep carriers.

Actually it would work on a Jeep carrier as well. Same length as a Wildcat, actually stalled 3 mph slower than an F4F-3, wings folded it was I think 21 feet 6 inches wide. Obviously that weight would come up a bit as would stall speed, but on a Jeep carrier it could also replace the Wildcat and Avenger. Only plane you need there as well.

On a Jeep carrier, 4 50's in the nose are great for strafing surfaced U boats. It could carry a good load of bombs or depth charges. With 400 gallons of fuel it would have great range and loiter time. It could defend against FW200 recon aircraft. Twin engine reliability to get you back to the carrier over the cold Atlantic. Outer wingspan could be increased if you wanted to land slower or lift heavier loads, Avenger wingspan was 50'

 

[Kevin J]

Actually it would work on a Jeep carrier as well. Same length as a Wildcat, actually stalled 3 mph slower than an F4F-3, wings folded it was I think 21 feet 6 inches wide. Obviously that weight would come up a bit as would stall speed, but on a Jeep carrier it could also replace the Wildcat and Avenger. Only plane you need there as well.

Dive speed isn't phenomenal, but 450 mph is good enough to deal with all Axis bombers, the Zero, and to catch Fw 190A fighter-bombers. Whirlwind is a bit slow in a dive.

 

[pinsog]

Dive speed isn't phenomenal, but 450 mph is good enough to deal with all Axis bombers, the Zero, and to catch Fw 190As.

It was actually dived vertically to 505 mph on February 1, 1941.

 

[Kevin J]

It was actually dived vertically to 505 mph on February 1, 1941.

I thought it only did 450 mph.

 

[RCAFson]

Building the P-50 took up valuable time. Getting the F5F into service mid 1942 for the FAA looks more than feasible and its a much better plane than the Wildcat. You'd still need the latter for the jeep carriers.

The F5F didn't fly until April 1940 and was much slower than anticipated:

http://www.alternatewars.com/SAC/Notes_on_the_History_of_the_XF5F-1.htm

given that Grumman was already overloaded, the F5F is really a non-starter.

 

[pinsog]

The F5F didn't fly until April 1940 and was much slower than anticipated:

http://www.alternatewars.com/SAC/Notes_on_the_History_of_the_XF5F-1.htm

given that Grumman was already overloaded, the F5F is really a non-starter.

The top group is from the actual test. The engines were only putting out 1000 hp from SL to 4500 ft and only putting out 900 hp from 7300 to 14000 feet. Even so, it was still 30-35 mph faster than an F4F-3 up to 17,000 feet and about 15 mph faster at 20,000 where the single stage Wright's were running out of air.
312 mph at SL on 2,000 hp
326 mph at 4500 ft on 2,000 hp
324 mph at 7300 ft on 1,800 hp
346 mph at 14,000 ft on 1,800 hp
352 mph at 20,000 ft on 1500 hp

Below is what it would do with Wright engines used in the Wildcat. Now it is 55 mph faster than an F4F-3 Wildcat at sea level
With uprated Wright's from a Wildcat
331 mph at SL on 2400 hp
346 mph at 4500 ft on 2400 hp
335 mph at 7300 ft on 2000 hp
358 mph at 14,000 ft on 2000 hp
364 mph at 20,000 ft

This is what it would do with 2 stage P&W engines, not including that each P&W had 3.5 square feet less frontal area than a Wright.
With 2 stage P&W (not including 7 square feet less frontal area on the engines)
331 mph at SL on 2400 hp
346 mph at 4500 ft on 2400 hp
346 mph at 7300 ft on 2200 hp
358 mph at 14000 ft on 2000 hp
387 mph at 20,000 ft on 2000 hp


The Navy whined the F5F was overweight and then bought the Corsair and Hellcat which were both even heavier.

I have said it several times, if you read the history of the XF5F, Grumman didn't work on it, they were too busy with the Wildcat. It sat for long periods of time. There was nothing innovative about it, no fancy engines or new technology, it was a Wildcat body with a bigger wing and 2 engines. If they had abandoned the Wildcat and focused on the XF5F they would have had no trouble getting it into service about the same time.

 

[RCAFson]

The top group is from the actual test. The engines were only putting out 1000 hp from SL to 4500 ft and only putting out 900 hp from 7300 to 14000 feet. Even so, it was still 30-35 mph faster than an F4F-3 up to 17,000 feet and about 15 mph faster at 20,000 where the single stage Wright's were running out of air.
312 mph at SL on 2,000 hp
326 mph at 4500 ft on 2,000 hp
324 mph at 7300 ft on 1,800 hp
346 mph at 14,000 ft on 1,800 hp
352 mph at 20,000 ft on 1500 hp

Below is what it would do with Wright engines used in the Wildcat. Now it is 55 mph faster than an F4F-3 Wildcat at sea level
With uprated Wright's from a Wildcat
331 mph at SL on 2400 hp
346 mph at 4500 ft on 2400 hp
335 mph at 7300 ft on 2000 hp
358 mph at 14,000 ft on 2000 hp
364 mph at 20,000 ft

This is what it would do with 2 stage P&W engines, not including that each P&W had 3.5 square feet less frontal area than a Wright.
With 2 stage P&W (not including 7 square feet less frontal area on the engines)
331 mph at SL on 2400 hp
346 mph at 4500 ft on 2400 hp
346 mph at 7300 ft on 2200 hp
358 mph at 14000 ft on 2000 hp
387 mph at 20,000 ft on 2000 hp


The Navy whined the F5F was overweight and then bought the Corsair and Hellcat which were both even heavier.

I have said it several times, if you read the history of the XF5F, Grumman didn't work on it, they were too busy with the Wildcat. It sat for long periods of time. There was nothing innovative about it, no fancy engines or new technology, it was a Wildcat body with a bigger wing and 2 engines. If they had abandoned the Wildcat and focused on the XF5F they would have had no trouble getting it into service about the same time.

Removing the F4F and Martlet makes a big hole in USN and FAA aircraft procurement.

How much would the F5F weigh with fuel, armour, SS tanks and a full ammo load?

Also it's minimum folded width is 20ft or more. FAA spec was 18ft, to fit on 22ft width lifts.