British escort fighter--what might it have been like? (2 Viewers)

[tomo pauk]

Only range figures I've seen for the Spiteful was 564 miles on internal fuel and 1315 miles with drop tanks (Old Machine Press' article on the Spiteful and Seafang).

I know, this is why I've said that math does not add up.
See here for Seafire 47 mileage. Also see here for Spitfire XIV doing 490 miles with allowances on 120 imp gals, and 640 on 150 gals.
Both of these were draggier than the Spiteful. OTOH, it is very much possible that Spitfeful was not using the rear tank in service.

However, I'd bet that a Merlin Spiteful would've been a good deal lighter than the Griffon version, and probably less fuel thirsty.

This is an idea with a merit IMO.

 

[BarnOwlLover]

If that was the case, it seems that the Spiteful had the same directional stability/CG issues that Spitfires had with the rear fuselage tanks when filled above a certain levels. The Merlin Mustangs also tended to have the same issues until the P-51H was designed (smaller tank teamed with larger tail unit). This could be due to the Spiteful's Spitfire hereitage, though the Spiteful did diverge into basically a new aircraft by the time it was production ready.

Hence why I do agree with the thought that such an aircraft as what I'm asking about would probably have to be designed for the role of escort or being capable of both escort and interception from scratch, and not just a reworking of an existing design.

 

[tomo pauk]

If that was the case, it seems that the Spiteful had the same directional stability/CG issues that Spitfires had with the rear fuselage tanks when filled above a certain levels.

It seems to me that institutional inertia was alive and well in the RAF.

Hence why I do agree with the thought that such an aircraft as what I'm asking about would probably have to be designed for the role of escort or being capable of both escort and interception from scratch, and not just a reworking of an existing design.

At the end of the day, the best escorts were versions of existing designs.

 

[BarnOwlLover]

Again, as pointed out, the suggestion that you can just take a Spitfire for example, and pack more fuel in it, probably isn't the way to go. You'd have to change so much in a design that was never really optimized for long range flight to begin with. Even the Mustang needed added fuel to make it a true escort fighter once the Merlin was installed in it, and it already was carrying basically twice the fuel of a Merlin Spitfire.

For instance, it's already been stated that the best and most obvious place to put fuel is at or very close to the aircraft's intended CG. Being able to maintain CG with varying fuel levels and capacities has to be basically built into the design. The Mustang and Spitfire ended up having long range tanks fitted to them that though they boosted range, compromised the aircraft's handling and performance when filled above a certain point due to CG shift and trim changes.

All of this has to be considered on a single seat, single engine fighter, and the smaller the aircraft, the less room you have to put stuff and optimize its position. However, as has been shown by examples mentioned, it's certainly not impossible, though certainly improbable with a relatively small aircraft by pre-1942 standards.

 

[wuzak]

However, I'd bet that a Merlin Spiteful would've been a good deal lighter than the Griffon version, and probably less fuel thirsty.

A Merlin Spiteful was certainly considered, that being why the first Griffon Spiteful was the XIV.

The question is would it have been as capable as the Griffon Spiteful?

 

[tomo pauk]

Again, as pointed out, the suggestion that you can just take a Spitfire for example, and pack more fuel in it, probably isn't the way to go. You'd have to change so much in a design that was never really optimized for long range flight to begin with. Even the Mustang needed added fuel to make it a true escort fighter once the Merlin was installed in it, and it already was carrying basically twice the fuel of a Merlin Spitfire.

Taking out a Spitfire and pack more fuel in it was a way to go. It was done, admittedly in a slow fashion, and eventually too late, under the doctrine that was against making long-range fighters. It was also done with Tempest, too.
Too bad that the RAF didn't specified a Spitfire IX and VIII having rear fuel tanks of 30-50 gals already by late 1942, and the Mk.XIV by late 1943.
Packing more fuel in a fighter, especally if paired with addition of drop tanks, was what it was done in many other countries so the range/radius is much improved, too.

All of this has to be considered on a single seat, single engine fighter, and the smaller the aircraft, the less room you have to put stuff and optimize its position. However, as has been shown by examples mentioned, it's certainly not impossible, though certainly improbable with a relatively small aircraft by pre-1942 standards.

By pre-1942 European standards, Spitfire was one of biggest 1-engined fighters. It was much easier to make a LR Spitfire than a LR version of Bf 109, Soviet or Italian fighters.
What stood between imaging such a Spitfire and actually making it for service use was the then-current RAF doctrine.

 

[Macandy]

Spitfire as a long range fighter?
Can't be done.
The MkIX was 30mph slower on the same power as a P-51 despite being smaller - the Mustang had much lower drag from its wings and especially radiators
The Spitfire was very limited on what it could carry under its wings - trials of large Mustang drop tanks were 'interesting' - as in they wouldn't separate cleanly and dented the wings

 

[BarnOwlLover]

IMO, the Spitfire would work if it was designed to be longer ranged to begin with. IMO, trying to squeeze 800+ mile range on internal fuel out of a plane designed originally for a 500 mile range doesn't IMO make much sense, not without a major redesign. And even the suggestion of installing rear fuselage mounted tanks on a Spitfire doesn't make much sense as they played havoc on CG/directional stability when filled above a certain level. If as one posted noted you want high cruising speed, excellent speed and maneuverability, and things like a low drag or ducted radiator (ventral or wing leading edge, or even a Spiteful or enhanced Spitfire arrangement), and heavy armament, you basically need either a fresh design or a design that has most of those in it and doesn't take a ton of modification to add the missing feature.

Speaking of radiators, would a radiator like what the Napier Heston Racer or Airspeed's Sabre fighter concepts used (both of which exhausted the radiator out of the tail unit area) make sense for such an aircraft or a single seat single engine figher in general?

 

[tomo pauk]

IMO, the Spitfire would work if it was designed to be longer ranged to begin with. IMO, trying to squeeze 800+ mile range on internal fuel out of a plane designed originally for a 500 mile range doesn't IMO make much sense, not without a major redesign.

Are you aware of the Spitfire Mk.VIII? 740 miles cruise on 120 gals internal fuel, plus allowances - not a single drop of it being behind the pilot. Same fuel tankage was carried by Spitfire VII.

And even the suggestion of installing rear fuselage mounted tanks on a Spitfire doesn't make much sense as they played havoc on CG/directional stability when filled above a certain level.

If you feel that two tanks are too much (65-70-ish imp gals total), install just one tank per Mk.VII/VIII/IX, 30-35 gals. Or use the 29 imp gal tank aft the pilot as used on Spitfire Vs for overseas deployment:

If as one posted noted you want high cruising speed, excellent speed and maneuverability, and things like a low drag or ducted radiator (ventral or wing leading edge), and heavy armament, you basically need either a fresh design or a design that has most of those in it and doesn't take a ton of modification to add the missing feature.

Excellent speed and maneuverability are already there. Armament was more that sufficient.
What is needed is a suitable doctrine, so that RAF lifts the head out from the sand and make provision for a fighter that can be a part of the meat grinder above Germany proper. This means adding extra fuel tankage, 1st and foremost.
This will also mean that Tempest has 190 imp gals internal (or more) from day one, not 160 gals, and that Spitfire XIV will have the rear fuselage tank, also from day one.
See here for 188 imp gals internal fuel on Tempest, very CoG neutral (leading edge position), unfortunately that modification was in use by the time Allies were well in France.
Both Spitfire and Tempest check the box at 'design that can be had in a very short time'.

Speaking of radiators, would a radiator like what the Napier Heston Racer or Airspeed's Sabre fighter concepts used (both of which exhausted the radiator out of the tail unit area) make sense for such an aircraft or a single seat single engine figher in general?

Why not?
Perhaps that can be improved with introduction of the boundary layer splitter?

 

[BarnOwlLover]

The Napier Heston Racer did have a boundary layer splitter in the front of the intake. Not sure about the Airspeed aircraft since those were basically design exercises.

If you want to improve the Tempest's aero, you'd have to redesign the radiator, since the chin radiator wasn't insanely aero efficent (though aero suggested it was better than the Tornado's early Hurricane-esque ventral radiator due to compressiblity problems). That means either reviving the leading edge radiators (which would displace the leading edge fuel tanks as on the Tempest I, and those tanks weren't fitted to the Tempest V as standard until after the Allies established themselves in France), or fitting a Mustang-type ventral radiator (envisioned for the Hawker P1027, which was never built, and would've required a redesign of the Tempest's rear fuselage).

Again, you'd probably be better off with a purpose made design than trying to shoe-horn all of those features into a Spitfire or even a Tempest, even if the Tempest is closer to what I'm asking for in terms of overall performance. Not to mention that most Spitfires aside from some in North Africa still carried rifle caliber machine guns along side 2x20mm cannons well into the war until the E-wing (2x.50 MG, 2x20mm cannon) became a common fit in 1944. And it wasn't until the Spitfire 21 that 4 cannon armament was standardized. The Battle of Britain showed the rifle caliber machine guns were barely adequate for fighter vs fighter combat in 1940, and weren't great on bombers, either. The fact that most German fighters were also armed with a mix of rifle caliber MGs and 20mm cannon until 1943 also astounds me.

A better choice IMO, certainly by 1942, was 6-8 HMGs, a mix of cannons and HMGs, or go all cannon.

And even for the Spitfire to be longer ranged, or get a longer ranged fighter before the Merlin Mustang would've indeed taken rethinking on the part of the RAF and the Air Ministry. But then again, until the Merlin Mustang, the RAF either thought such a fighter was impossible, or not worth while due to being wedded to the concept or night bombing.

 

[tomo pauk]

If you want to improve the Tempest's aero, you'd have to redesign the radiator, since the chin radiator wasn't insanely aero efficent (though aero suggested it was better than the Tornado's early Hurricane-esque ventral radiator due to compressiblity problems). That means either reviving the leading edge radiators (which would displace the leading edge fuel tanks as on the Tempest I, and those tanks weren't fitted to the Tempest V as standard until after the Allies established themselves in France), or fitting a Mustang-type ventral radiator (envisioned for the Hawker P1027, which was never built, and would've required a redesign of the Tempest's rear fuselage).

I'm satisfied with Tempest's aero, it is the Germans that need to step up their game inn 1944.

Again, you'd probably be better off with a purpose made design than trying to shoe-horn all of those features into a Spitfire or even a Tempest, even if the Tempest is closer to what I'm asking for in terms of overall performance.

Installing greater fuel tankage on Spitfire and Tempest should be called 'shoehorning', but when Amerucans do it, it is a touch of genius? I'm just listing out things what were actually done with aircraft much before P-51B or P-47D were operational in the UK.

Not to mention that most Spitfires aside from some in North Africa still carried rifle caliber machine guns along side 2x20mm cannons well into the war until the E-wing (2x.50 MG, 2x20mm cannon) became a common fit in 1944. And it wasn't until the Spitfire 21 that 4 cannon armament was standardized. The Battle of Britain showed the rifle caliber machine guns were barely adequate for fighter vs fighter combat in 1940, and weren't great on bombers, either. The fact that most German fighters were also armed with a mix of rifle caliber MGs and 20mm cannon until 1943 also astounds me.

Two cannons are more than enough to kill anything Luftwaffe puts in the air. The .303s were a back-up.

 

[Shortround6]

Two cannons are more than enough to kill anything Luftwaffe puts in the air. The .303s were a back-up.

It is strange that when the British use .303 ammo it is pea shooter stuff that barely scratches the paint.
When the Italians use it (in 1/2 the number of guns that fire slower) it is a useful supplement to the 12.7s.

AND when the Japanese use it it (again slower firing guns) was good enough to help conquer wide areas of South East Asia and nearly bring the US to their knees in 1942.

Here is an idea.
Slow the .303 Browning's down to 800-900 rpm instead of 1100-1200rpm for greater effectiveness.

 

[GrauGeist]

There is an incredibly long list of aircraft lost and/or crew killed by "rifle caliber" MGs by all sides (Axis/Allied).

 

[BarnOwlLover]

Uhm, I never said it was genius on the Mustang. To get the range on the Mustang up, rear fuselage fuel tanks were added, like on several versions of the Spitfire. And like on the Spitfire, it caused trim/CG/directional stability problems. I've mentioned this for the Mustang several times. There's a reason the XP-51F/G didn't use it, and why when it came back on the P-51H it was a lot smaller.

IMO, a good case study could've been the DH Comet racer. Even though it was twin engine, it had several things that should've been studied or observed, such as a high cruse speed, relatively small for the fuel it carried, etc. Granted, using a Merlin would eat into that, as well as cannon armament, armor and self sealing tanks, but what was stopping the RAF from saying in 1940 after the first Mosquito (which embodied a lot of lessons and concepts from the Comet), "we want a single seat, single engine long range fighter of certain range and performance specs"?

Well, other than the fact that the RAF would have to realize the need or purpose of such an aircraft, and probably having to wait until 1942 for the Merlin 60 series and later engines, you also have to ask who'd build it. If the RAF wanted to keep the Spitfire and the Typhoon and Tempest lines as interceptors and/or ground attack (where long range doesn't mean as much), that's Hawker and their group of companies and Supermarine and Vickers out of the running, DH were building the Mosquito and working on the Hornet and Vampire, everyone else was building bombers, recon aircraft, trainers or were subconractors to other programs.

Thus, either someone outside of the established system would have to design it, or an established maker could design it, but someone else would have to make it. Which sort of happened with the Mustang on the British end.

As far as armament, even in 1940, it was realized that rifle caliber machine guns posed limited threat to aircraft that had decent armor and decent self sealing fuel tanks, as well as decently strong structures. England and France were thinking of adopting the 13.2mm FN machine guns (basically an AN-M2 Browning re-barrelled to fire the 13.2x99mm Hotchkiss HMG round instead of .50 BMG), but Belgium was overrun before that happened. Germany realized during the Battle of Britain that the low velocity 20mm MG FF cannons were obsolescent and the 13mm MG131 was the better bet, or for sure the 20mm MG151 (which was being designed at the time).

Of course, a lot of this as far as range could've been resolved if the RAF was a bit more open to either having multi-role fighters and possible tactical and strategic changes or trends, or maybe changes in aircraft design, even if they stuck to their guns (especially on the Spitfire) out of the "quantity is its own quality" deal.

 

[tomo pauk]

IMO, a good case study could've been the DH Comet racer. Even though it was twin engine, it had several things that should've been studied or observed, such as a high cruse speed, relatively small for the fuel it carried, etc. Granted, using a Merlin would eat into that, as well as cannon armament, armor and self sealing tanks, but what was stopping the RAF from saying in 1940 after the first Mosquito (which embodied a lot of lessons and concepts from the Comet), "we want a single seat, single engine long range fighter of certain range and performance specs"?

This is my butchering of the DH.88, 1-engined spin-off. Note the wings a bit clipped, too.

 

[GrauGeist]

For factory installed, internal fuel capacity:
XP-51 - 170 gallons.
P-51A - 180 gallons.
P-51B/C/D/K - 269 gallons.
P-51H - 255 gallons.
XP-51F/G/J - 105 gallons.

 

[Shortround6]

IMO, a good case study could've been the DH Comet racer. Even though it was twin engine, it had several things that should've been studied or observed, such as a high cruse speed, relatively small for the fuel it carried, etc. Granted, using a Merlin would eat into that, as well as cannon armament, armor and self sealing tanks,

• Empty weight: 2,930 lb (1,329 kg)
• Max takeoff weight: 5,550 lb

The Comet was designed to be a long range "racer" it was not designed to perform combat maneuvers. Please add hundreds of pounds (or over 1,000) of structural weight for combat. (
It does help illustrated some of the problems. If you want a lot of fuel in a small airplane it either needs to go close to the center of gravity or you need a lot of tanks stuck in out of the way places and careful fuel management (don't have tank in use go dry at an embarrassing moment).

Spitfire I with wooden prop
Structure 1890lbs
Power plant 2,035lbs
Load (pilot, fuel (84 Inp Gal) , guns, etc) 1585lbs
"Sundries" 365lbs
Total,,,,,,,,,,,,,,,,,5875lbs

Thus, either someone outside of the established system would have to design it, or an established maker could design it, but someone else would have to make it.

Trouble was there was nobody to make it, established or otherwise. There was no spare capacity in Great Britain and not much in Canada (or anywhere else). There were no empty factories (with or without machinery) and no labor force sitting around have tea waiting for something to do. Canada (not slight the rest of the Commonwealth) did great things, but, they often had to wait for the US to supply the machine tools/equipment. British Machine tools were being absorbed by existing industries as fast as they could be produced.

. England and France were thinking of adopting the 13.2mm FN machine guns (basically an AN-M2 Browning re-barrelled to fire the 13.2x99mm Hotchkiss HMG round instead of .50 BMG), but Belgium was overrun before that happened. Germany realized during the Battle of Britain that the low velocity 20mm MG FF cannons were obsolescent and the 13mm MG131 was the better bet, or for sure the 20mm MG151 (which was being designed at the time).

Both German guns had been in design/development for several years in 1940.
The FN guns are rather phantom like. They existed in small quantities, and that means we are back to the production problem. FN never made very many. The actual performance is subject to question. It took the US four years with 3 different companies working on projects (none of the them Colt) to get to the rate of fire that FN claimed. Of course FN never listed the jam/malfunction rate either.
Now who was supposed to make them for the British?
At one point in WW II the Americans had 9 companies making the M2 Browning. Some were established gun companies, others were places like A C Spark Plug, Saginaw Division of GM, Kelsey-Hayes Wheels.

 

[Shortround6]

XP-51F/G/J - 105 gallons.

Was the XP-51F/G/J really 105 gallons or was that some slight of hand to get the weight where they wanted it?
the April 1940 specs for the Mustang I show a range of 640 miles with standard fuel (amount not given) and 1022 miles with overload fuel.
Long nose P-40s were rated at 105 gal fuel "normal" and about 160 gal overload when the rear tank was filled (same for the P-36).
Navy was pulling the same trick with Buffalo, F4F and F4U. Just don't fill the tank/s when measuring the climb, ceiling, etc.

 

[pbehn]

It is strange that when the British use .303 ammo it is pea shooter stuff that barely scratches the paint.
When the Italians use it (in 1/2 the number of guns that fire slower) it is a useful supplement to the 12.7s.

AND when the Japanese use it it (again slower firing guns) was good enough to help conquer wide areas of South East Asia and nearly bring the US to their knees in 1942.

Here is an idea.
Slow the .303 Browning's down to 800-900 rpm instead of 1100-1200rpm for greater effectiveness.

Or call it 30 Cal, then its a real killer.

 

[PAT303]

It is strange that when the British use .303 ammo it is pea shooter stuff that barely scratches the paint.
When the Italians use it (in 1/2 the number of guns that fire slower) it is a useful supplement to the 12.7s.

AND when the Japanese use it it (again slower firing guns) was good enough to help conquer wide areas of South East Asia and nearly bring the US to their knees in 1942.

Here is an idea.
Slow the .303 Browning's down to 800-900 rpm instead of 1100-1200rpm for greater effectiveness.

Don't forget to take out the communications equipment, life raft and parachute, rear pilot armour, front armored windscreen, self sealing tanks, six of the eight guns and optimise the handling for under 200mph and it would be a war winner. Bloody Mitchell, he knew nothing about aircraft.