1941: the best case for 350+ mph CV fighters?

[GrauGeist]

Dave - doable but while production of the NA-73 began in spring 41, modifying the Mustang for just carrier landing qual - much less hosting a nasty inline/glycol cooled engine was Never going to be bought by USN. The earliest possible date for Carrier qual 'qualified' acceptance would have been perhaps mid 1942 for the NA-73. The NA-91 shown above first flew in May, 1942 and was acquired from Brit order.At that time the F4U had much more upside. Further, adding wing racks/plumbing was NA-97 (A-36) first flying in Fall 1942. Earliest delivery to squadron level would have been mid 1943 if USN committed in April 1942.

Yeah, we had a lengthy discussion several years ago about water-cooled aircraft versus the USN mindset by the late 30's - also, their existing carriers would have had to be retrofitted for Glycol storage and the carriers under construction would have to be modified as well. Considering the USN was under severe budget constraints by 40/41, I honestly doubt the P-51 or XFL were ever seriously considered beyond testing (pre-war).
The USN was actually interested in the P-51D and P-51H later on, but that's for another discussion.

 

[pinsog]

Tomo Pauk,

Could you please explain "Calibrated Climbing Speed" to me?
I'm having a little trouble understanding the figures they show in that link you posted.

Elvis, I just realized you weren't talking to me and on a completely different subject. I guess I should read posts a little closer.

You were talking about the P43 graph. My mistake

 

[fliger747]

A misunderstanding of what the "tail" does on an airplane. To produce positive stability the tail produces downforce. At the "cut" on a power on approach to landing The downforce on the tail reduces and the NOSE drops. This mains first contact would often cause the "bounce" as the tail then dropped at impact increasing the AOA and the plane wanting to re fly for a last gasp, perhaps over the wires.

From a previous post...

The 'float' was actually caused not by excessive speed but by the inescapable consequences of the V squared law. When a pilot cut the power to land and the slipstream speed reduced, the extra lift given by the positive angle on the elevator also reduced. The tail then lost a good deal of its lift and inevitably fell.

 

[XBe02Drvr]

At the "cut" on a power on approach to landing The downforce on the tail reduces and the NOSE drops. This mains first contact would often cause the "bounce" as the tail then dropped at impact increasing the AOA and the plane wanting to re fly for a last gasp, perhaps over the wires.

Or in the case of a nosedragger, it hits nosegear first, then mains, with nose bouncing up, plane relaunching into the air, only to stall and drop in on its nose again, while the panicked student freezes on the controls with the throttle not all the way off, and the plane crowhops off the end of the runway and into the thules. (or off the angle deck into the drink)
I saw this happen to a student carrier qualing on the Lex in a T-28. He crow hopped over all four wires and disappeared over the angle as the LSO screamed "POWER, POWER", but he managed to catch it with power before it hit the water. From our vantage point in the PLAT camera station on the island, we saw a lot of spray churned up by his prop and thought he'd gone in, but he reappeared skimming the wavetops. Needless to say, they bingoed him right back to Whiting. I'm guessing that was the end of his aviation career.
Cheers,
Wes

 

[Kevin J]

Well, the elephant in the room are the German and British conversions that coulda and shoulda, but never eventuated (well not quite true, the Me109T, the conversion of the E-3 was completed, but never flew from a carrier, the me 109f was only ever projected, whilst the seafire did happen and was used from a carrier but arrived vary late for the party). I am referring to the Me-109T and Me 109F conversions (mooted) for the failed KM carrier. For the British the missing thoroughbred was the seafire II, which the admiralty had wanted since at least 1939, but consistently rejected by an indifferent, even hostile air ministry.


The seafire needed some work, undoubtedly, but none of it was technically infeasible. The chief changes required were wing folding, strengthened landing gear, redesigned and widened landing gear as opposed to the narrow tracked types accepted for the land based version.


It would take until the Seafire III series before anything like a decent navalised version of the Spitfire was produced. It could have happened years before it did

I'd dispute that. The Seafire needed the strengthened wing of the Spitfire Vc. I certainly don't believe it could have arrived earlier.

 

[Kevin J]

I think the closest you could get would be a Hurricane IIa, no wing folding, cleaned up, arrestor hook only, individual exhaust stubs. My estimate 348 mph. Alternately, Hawker Hotspur with Rolls-Royce Vulture, under fuselage radiator, turret replaced with fuel tank and armament in wings N.B. Henley flew with Vulture. Problem is the radiator would be a big scoop for water if the plane had to ditch. Perhaps not the safety standards required of a plane that could have flown before WW2. Or maybe a Sea Defiant, turret replaced with fuel tank, armament in wings, arrestor hook, upwards wing folding, optional catapult attachments. Early version Spitfires I/II/Va/b, definitely not, its too fragile.

 

[wuzak]

I think the closest you could get would be a Hurricane IIa, no wing folding, cleaned up, arrestor hook only, individual exhaust stubs. My estimate 348 mph.

Since the land plane version of the Hurricane II couldn't do that, it would be very doubtful that a Sea Hurricane could.

Alternately, Hawker Hotspur with Rolls-Royce Vulture, under fuselage radiator, turret replaced with fuel tank and armament in wings N.B. Henley flew with Vulture. Problem is the radiator would be a big scoop for water if the plane had to ditch. Perhaps not the safety standards required of a plane that could have flown before WW2.

The Henley was used as a test bed for the Vulture.

Hawker had difficulty with the under-fuselage radiator on the Tornado, moving it to the nose after early flights. It is hard to know if Hawker could have made it work for the Hotspur in conjunction with the Vulture.

And then, of course, you are stuck with an engine which is out of production by early 1941, only 500 or so having been made.

Or maybe a Sea Defiant, turret replaced with fuel tank, armament in wings, arrestor hook, upwards wing folding, optional catapult attachments. Early version Spitfires I/II/Va/b, definitely not, its too fragile.

Maybe a Sea Defiant could work, if they weren't required for other duties.

The proposals for the early Spitfire based Seafire had revised wings with folds and strengthening. One even had a trapezoidal wing, rather than the elliptical wing.

 

[Shortround6]

I think the closest you could get would be a Hurricane IIa, no wing folding, cleaned up, arrestor hook only, individual exhaust stubs. My estimate 348 mph. Alternately, Hawker Hotspur with Rolls-Royce Vulture, under fuselage radiator, turret replaced with fuel tank and armament in wings N.B. Henley flew with Vulture. Problem is the radiator would be a big scoop for water if the plane had to ditch. Perhaps not the safety standards required of a plane that could have flown before WW2. Or maybe a Sea Defiant, turret replaced with fuel tank, armament in wings, arrestor hook, upwards wing folding, optional catapult attachments. Early version Spitfires I/II/Va/b, definitely not, its too fragile.

Henley with Vulture engine

Please note that many large, 2/3 seat aircraft were used for engine test beds because they had the room for extra engine instruments and room for one or more test engineers to monitor the engine and not be bothered flying the plane. Few, if any, carried any armament or other combat equipment. No mention is ever made of any ballast being carried to get the CG in proper position for safe flying as few dozen or few hundred pounds of ballast in the tail was of little importance. The idea being to get a number of hours on the engine in an environment different from the test stand in the test house to see if any unforeseen problems came up.

I have to wonder why so many people want to use the Defiant as a basis for some other type or mission aircraft.
You can't put a fuel tank where the turret was,

it is too far behind the CG. You could put the fuel tank where the pilot is and then move the pilot to where the turret was for a truly dismal forward view.
The plane only had a 250sq ft wing, in between a Spit and a Hurricane and had a gross weight roughly 2000lbs heavier, take off and landing speeds would be higher than either one and no, the turret was NOT responsible for ALL the extra weight, at least not directly. If you yank the turret from an existing airframe you save around 600lbs and since there is no longer a gunner you save another 200lbs (depending on how well fed he was, the 200lbs includes his parachute and his personal dinghy). A lot of the "extra" weight was the heavier structure needed to support the weight of the turret or to meet the load standards for the heavier gross weight. You could lighten up the structure but that means redoing the stress/strength calculations for every part of the airframe.
Just design a new airplane to begin with, you aren't saving much.

 

[Kevin J]

Since the land plane version of the Hurricane II couldn't do that, it would be very doubtful that a Sea Hurricane could.




The Henley was used as a test bed for the Vulture.

Hawker had difficulty with the under-fuselage radiator on the Tornado, moving it to the nose after early flights. It is hard to know if Hawker could have made it work for the Hotspur in conjunction with the Vulture.

And then, of course, you are stuck with an engine which is out of production by early 1941, only 500 or so having been made.




Maybe a Sea Defiant could work, if they weren't required for other duties.

The proposals for the early Spitfire based Seafire had revised wings with folds and strengthening. One even had a trapezoidal wing, rather than the elliptical wing.

The Sea Hurricane IIc did 342 mph which was 6 mph faster than the Hurricane IIc.

Yes, the Vulture went out of production, but its problems were no worse than the Sabre. Perhaps if the Vulture had a service to champion it. Frankly, I wouldn't go for it though as its ditching characteristics would be awful.

I've never seen any proposal for a new wing on the early Spitfire. Only the proposal that the wings be folded back.

 

[Kevin J]

Henley with Vulture engine
View attachment 537910

Please note that many large, 2/3 seat aircraft were used for engine test beds because they had the room for extra engine instruments and room for one or more test engineers to monitor the engine and not be bothered flying the plane. Few, if any, carried any armament or other combat equipment. No mention is ever made of any ballast being carried to get the CG in proper position for save flying as few dozen or few hundred pounds of ballast in the tail was of little importance. The idea being to get a number of hours on the engine in an environment different from the test stand in the test house to see if any unforeseen problems came up.

I have to wonder why so many people want to use the Defiant as a basis for some other type or mission aircraft.
You can't put a fuel tank where the turret was,
View attachment 537911
it is too far behind the CG. You could put the fuel tank where the pilot is and then move the pilot to where the turret was for a truly dismal forward view.
The plane only had a 250sq ft wing, in between a Spit and a Hurricane and had a gross weight roughly 2000lbs heavier, take off and landing speeds would be higher than either one and no, the turret was NOT responsible for ALL the extra weight, at least not directly. If you yank the turret from an existing airframe you save around 600lbs and since there is no longer a gunner you save another 200lbs (depending on how well fed he was, the 200lbs includes his parachute and his personal dinghy). A lot of the "extra" weight was the heavier structure needed to support the weight of the turret or to meet the load standards for the heavier gross weight. You could lighten up the structure but that means redoing the stress/strength calculations for every part of the airframe.
Just design a new airplane to begin with, you aren't saving much.

IIRC the turret including gunner was 600 lbs which was at the c.g. of the aircraft.

 

[Kevin J]

IIRC, the primary pre-war requirements for the FAA were loiter endurance, all weather capability, and the speed necessary to intercept recce and patrol aircraft. Hence the Fulmar. However once the FAA was operating in contested waters and opposed by the Me 110, they needed something faster. The Hurricane Ib/1c with 12/16 lbs boost satisfied that need. The Seafire must have been disappointing when it eventually arrived. In WW2 in order of aircraft destroyed it was the Fulmar, Sea Hurricane then Seafire in that order. So the Admiralty must have got it right.

 

[XBe02Drvr]

IIRC the turret including gunner was 600 lbs which was at the c.g. of the aircraft.

That doesn't make sense. Look at the drawing SR6 provided. A CG aft of the trailing edge of the wing would make for an unflyable aircraft with divergent negative stability. And we all thought the Airacobra was bad!
Cheers,
Wes

 

[Shortround6]

IIRC the turret including gunner was 600 lbs which was at the c.g. of the aircraft.

If the turret was at the CG it is the only airplane in history to fly with the CG in line with trailing edge of the wing (or aft of it). This is for planes with one wing.

If you are right about the weight of the turret that just makes trying to convert a Defiant worse as pulling 600lbs instead of 800lbs means the basic airframe is that much heavier.

BTW the Prototype Hurricane MK II P.3269 (eight guns) was tested at 340mph at 20,000ft using 50.67in of absolute boost and 3020rpm. Not sure of the exhaust set up as the plane was being used to figure out/check on exhaust thrust calculations. Using 48.24in at 20,000ft the speed was 335mph.

The calculated hp to the prop was 1126hp in the first case and 1073hp in the 2nd, with 126.8hp (not pounds of thrust) added by the exhaust in the first case and 113hp in the 2nd case.

RR and Hawkers had both done calculations and Hawkers did the test flying and the calculations were in close agreement (but not identical ) and were close to the test flying results.

 

[XBe02Drvr]

If the turret was at the CG it is the only airplane in history to fly with the CG in line with trailing edge of the wing (or aft of it).

There may have been others, but if there were, their flights were very brief and very terminal.
Cheers,
Wes

 

[XBe02Drvr]

If the turret was at the CG it is the only airplane in history to fly with the CG in line with trailing edge of the wing (or aft of it).

Actually there was one historically. In 1912, Harriet Quimby was flying a Bleriot monoplane with a lifting tail and the CG aft of the wing, when it abruptly diverged, pitching down so sharply that it threw her and her passenger right out of the cockpit and into Boston harbor. Definitely terminal. Every lesson in the sky has been paid for in blood.
Cheers,
Wes

 

[Kevin J]

If the turret was at the CG it is the only airplane in history to fly with the CG in line with trailing edge of the wing (or aft of it). This is for planes with one wing.

If you are right about the weight of the turret that just makes trying to convert a Defiant worse as pulling 600lbs instead of 800lbs means the basic airframe is that much heavier.

BTW the Prototype Hurricane MK II P.3269 (eight guns) was tested at 340mph at 20,000ft using 50.67in of absolute boost and 3020rpm. Not sure of the exhaust set up as the plane was being used to figure out/check on exhaust thrust calculations. Using 48.24in at 20,000ft the speed was 335mph.

The calculated hp to the prop was 1126hp in the first case and 1073hp in the 2nd, with 126.8hp (not pounds of thrust) added by the exhaust in the first case and 113hp in the 2nd case.

RR and Hawkers had both done calculations and Hawkers did the test flying and the calculations were in close agreement (but not identical ) and were close to the test flying results.

AFAIK the Hurricane I did about 335 mph at 7000 feet with 16 lbs boost, the Sea Hurricane Ib, 20 mph less but only 308 mph at altitude. Both speeds being pretty good considering that you want the speed at low altitudes to protect your ships. The Hurricane I could out dive the Zero and was faster low down. Against an Me 110, which was much faster all round, I believe it all depended on the skill of the pilots involved, against the Zero, they would have needed the Thach weave to be effective.

 

[pinsog]

Why not a turbocharged F4F-3?

Original 2 speed 2 stage P&W R-1830-76:
1200 hp for takeoff
1100 hp from SL-2500 feet
1050 hp from 4800-11000 feet
1000 hp from 12200-19000 feet

with a P&W R-1830-47 with a turbocharger (same engine as the P43 Lancer)
1200 hp from SL-25000 feet

SL speed increases from 278 to 286
Speed at 5500 goes from 295 to 308
Speed at 13000 goes from 313 to 332
Speed at 19000 goes from 330 to 350
Speed at 22000 goes from 326 to 351

The F4F-3 speed numbers above included 150 pounds of armor and a self sealing fuel tank.

Drag should be identical, F4F-3 already has an intercooler so just plumb turbo into existing intercooler. I believe the weight would remain nearly the same as the weight of the turbo, 135 pounds, would be offset by the lighter single speed single stage engine that goes with it. I believe the best place for the turbo would likely be where it was on the P43 Lancer, but the pipe/plumbing would probably needed to have been done in the original prototype, not sure if there was room for the exhaust pipe and return pipe to be retrofitted later.
I also believe climb would be substantially improved as well as you would gain 100 hp down low, 200 hp from 12200-19000.

At 25000 feet HP jumps from 860 to 1200.

Performance virtually equal with the Spitfire mkII at 5000 feet and surpasses it above 20,000 and should continue to increase with altitude. (I can't find any speed data on the F4F-3 above 22000 feet)

 

[Shortround6]

Actually there was one historically. In 1912, Harriet Quimby was flying a Bleriot monoplane with a lifting tail and the CG aft of the wing, when it abruptly diverged, pitching down so sharply that it threw her and her passenger right out of the cockpit and into Boston harbor. Definitely terminal. Every lesson in the sky has been paid for in blood.
Cheers,
Wes

Well I did add this sentence after I first wrote it "This is for planes with one wing "

So we wouldn't get into things like.

or

Once you start using a secondary lifting surface then all bets are off on CG location (except it has to be between the two lifting surfaces and about where the balance of lift (?) would be.

The vast majority of aircraft (non swept wing jets, etc) flew with the CG somewhere in the high 20% of cord range. Say 27-30%? some may have exceeded that slightly.

 

[Kevin J]

Why not a turbocharged F4F-3?

Original 2 speed 2 stage P&W R-1830-76:
1200 hp for takeoff
1100 hp from SL-2500 feet
1050 hp from 4800-11000 feet
1000 hp from 12200-19000 feet

with a P&W R-1830-47 with a turbocharger (same engine as the P43 Lancer)
1200 hp from SL-25000 feet

SL speed increases from 278 to 286
Speed at 5500 goes from 295 to 308
Speed at 13000 goes from 313 to 332
Speed at 19000 goes from 330 to 350
Speed at 22000 goes from 326 to 351

The F4F-3 speed numbers above included 150 pounds of armor and a self sealing fuel tank.

Drag should be identical, F4F-3 already has an intercooler so just plumb turbo into existing intercooler. I believe the weight would remain nearly the same as the weight of the turbo, 135 pounds, would be offset by the lighter single speed single stage engine that goes with it. I believe the best place for the turbo would likely be where it was on the P43 Lancer, but the pipe/plumbing would probably needed to have been done in the original prototype, not sure if there was room for the exhaust pipe and return pipe to be retrofitted later.
I also believe climb would be substantially improved as well as you would gain 100 hp down low, 200 hp from 12200-19000.

At 25000 feet HP jumps from 860 to 1200.

Performance virtually equal with the Spitfire mkII at 5000 feet and surpasses it above 20,000 and should continue to increase with altitude. (I can't find any speed data on the F4F-3 above 22000 feet)

I can't see the point of a turbo in a Wildcat, after all you're not going to be intercepting bombers at that altitude, you need low altitude performance. The turbo and ducting is going to add weight and unnecessary complexity to the Wildcat. Manoeuvrability was bad enough as it was. Lets take off say 12 mph from your figures as per F4F-4 to account for that turbo and you're slower and less manoeuvrable at the altitudes where most of the fighting is going to take place. No, definitely not. As an interceptor I'd still prefer the Hurricane Ib/Ic in 1941/42 as it has its best performance low down where you need it followed by the Sea Hurricane IIb/c in 1942, then the Seafire LIIc in early 1943. As for the Seafire Ib use it primarily for training in 1941/42, the Seafire IIc, evaluation only in 1942/43. If you want a patrol and recce fighter then the Dauntless or the Fulmar, an escort / air superiority fighter then it must be the Wildcat as it has the best range and a reasonable performance.

I'm not even going to suggest the Miles M 20/2 as although it had good range, armament and performance, its made of wood and that's not going to last very long at sea. My Sea Defiant has already been knocked back as an idea. As an idea of what Boulton Paul could have done, have a look at the (Sea) Balliol which first flew in 1947 and had a service intro of 1950. What a crappy performance as a fighter this would have had, worse than a Sea Hurricane Ib/c.

Boulton Paul Balliol - Wikipedia

 

[pinsog]

I can't see the point of a turbo in a Wildcat, after all you're not going to be intercepting bombers at that altitude, you need low altitude performance. The turbo and ducting is going to add weight and unnecessary complexity to the Wildcat. Manoeuvrability was bad enough as it was. Lets take off say 12 mph from your figures as per F4F-4 to account for that turbo and you're slower and less manoeuvrable at the altitudes where most of the fighting is going to take place. No, definitely not. As an interceptor I'd still prefer the Hurricane Ib/Ic in 1941/42 as it has its best performance low down where you need it followed by the Sea Hurricane IIb/c in 1942, then the Seafire LIIc in early 1943. As for the Seafire Ib use it primarily for training in 1941/42, the Seafire IIc, evaluation only in 1942/43. If you want a patrol and recce fighter then the Dauntless or the Fulmar, an escort / air superiority fighter then it must be the Wildcat as it has the best range and a reasonable performance.

If you remove the 2 speed 2 stage engine from an F4F-3 and replace it with a single stage single speed engine you lose about 80 pounds. A B1 turbo weighs about 135 pounds. Not sure how much a couple of 12 foot long, 5 inch diameter sheet metal tubes weigh, but it isn't very much. The F4F-3 already has an intercooler for the 2 speed 2 stage engine we just removed, so we just use it for the turbo now. Lets say we gain 100 pounds.
To offset that 100 pound weight gain we now have: 1200 hp from SL-25000 feet,
that is 100 more hp from SL-2500 feet
150 more hp from 4800-11000 feet
200 more hp from 12200-19000 feet
340 more hp at 25000 feet

Where does more drag come in? the F4F-3 already had an intercooler which we still use with the turbo

F4F-3 was a bad maneuvering plane? An F4F-4 will turn inside of a Spitfire according to the Royal Navy. Compared to a Zero, anything turned bad at slow speeds except maybe a Gladiator.

Wildcats at Guadalcanal often fought, or at least started their fights at close to 30,000 feet. Took them about 40 minutes to get there. I imagine those guys would have welcomed a turbocharged Wildcat.