British escort fighter--what might it have been like?

BarnOwlLover

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I know that there'll be some variables here, namely time period and such, but what if the British had their own long range escort fighter? Naturally, it can't really be a Spitfire or a Hurricane since they're too short legged early war (and Spitfire for most of the war). But, from say 39-42, 42-45, what would a single seat, long range high performance escort fighter be like? The biggest thing as far as spec is enough fuel internally to have a 700-800 mile range, and the ability to use drop tanks. It also has to be heavily armed for the period (which from 42-45 basically means 4x20mm cannons), and be a great dogfighter per tactics of the period. This will address one of the few shortcomings of the P-51, given that it was a bit heavy due to being built to outdated USAAF load requirements (largely resolved with the H variant, but that doesn't really count here).

So I'll open the floor to the forum members to discuss.
 

tomo pauk

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Of the fighters that existed, the Spitfire. Another 40 imp gal behind the pilot, drop tank facility.
 

BarnOwlLover

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I'm talking about an indigenous British fighter, not the Mustang. Also, the early Mustang was Allison powered, which had a single stage supercharger. I also mentioned that this fighter should be lighter and more agile than the P-51D as well. I'd say that the P-51H could count, but didn't see use in Europe and barely got into service before VJ day.

Also, I mentioned two generations, 1939-42, then '42-45. And I wonder if I should add France, but they got knocked out of the War aside from the Free French after June 1940.
 

tomo pauk

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Also, I mentioned two generations, 1939-42, then '42-45.

Spitfires all the way?
Engine in 1939 and up to the late summer of 1940 is Merlin X (installed on the basic Spitfire I airframe), swap to the Merlin XX (on Spitfire III, since this one offers lower drag and more fuel by almost 20%). Start with 2-pitch props, switch to constant-speed types by early 1940. Sprinkle the engines with pressure-injection carbs by late 1939 (+10 mph, better ceiling, no negative G problems) and by more streamilned exhausts (extra 7-8 mph) - just copy the what the Bf 109E, He 112B and Ju 87B had.
1942 should see the 2-stage Merlins entering the stage, even if that means that Wellington VI does not materialize. Extra fuel at the leading edges.
Fuel - at least 30 imp gals tank behind the pilot before 1942, once the 2-stage engines are available move to a 50 gal tank. Try to copy the tank idea from Bf 109s by 1943 for less CoG-sensitive rear tankage? That will require shuffling of the controls/rods/lines under and behind the pilot.
Drop tanks at all the times, by 1942 try to have the American 150/165 US gal (roughly 135-140 imp gals) tanks as used on P-38.
Guns - the 8 .303s will do for a good part of the war for an escort fighter. No Hispanos before these are fully debugged and belt-fed, two cannons + two .50s after that will do for the duration of the war.
The 2-stage Griffon is nice-to have by mid-1944, but not necessary? Too bad there was no Griffon with a nice, big 1-stage S/C for 1943 and on.
 

PAT303

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Spitfires all the way?
Engine in 1939 and up to the late summer of 1940 is Merlin X (installed on the basic Spitfire I airframe), swap to the Merlin XX (on Spitfire III, since this one offers lower drag and more fuel by almost 20%). Start with 2-pitch props, switch to constant-speed types by early 1940. Sprinkle the engines with pressure-injection carbs by late 1939 (+10 mph, better ceiling, no negative G problems) and by more streamilned exhausts (extra 7-8 mph) - just copy the what the Bf 109E, He 112B and Ju 87B had.
1942 should see the 2-stage Merlins entering the stage, even if that means that Wellington VI does not materialize. Extra fuel at the leading edges.
Fuel - at least 30 imp gals tank behind the pilot before 1942, once the 2-stage engines are available move to a 50 gal tank. Try to copy the tank idea from Bf 109s by 1943 for less CoG-sensitive rear tankage? That will require shuffling of the controls/rods/lines under and behind the pilot.
Drop tanks at all the times, by 1942 try to have the American 150/165 US gal (roughly 135-140 imp gals) tanks as used on P-38.
Guns - the 8 .303s will do for a good part of the war for an escort fighter. No Hispanos before these are fully debugged and belt-fed, two cannons + two .50s after that will do for the duration of the war.
The 2-stage Griffon is nice-to have by mid-1944, but not necessary? Too bad there was no Griffon with a nice, big 1-stage S/C for 1943 and on.
The MkIII was fitted with a merlin 60 as a test bed aircraft, it was faster, harder rolling and had superior aerodynamics than any other model, I could have had a 96G main, 50G leading edge, rear 66G tanks plus 90G drop tank, right at max take off weight but so was many other fighters during the war, it would have plenty of range
 

pbehn

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Tell Hawkers to build the P-509 in 1939/40, then build P-51Bs instead of Spitfire Mk IXs, you have an allied escort available in numbers in 1943 so long range penetration missions can start 1 year earlier than they did historically. The British didnt have any need for a long range escort, the Americans only realised they had a need in 1943.
 

Shortround6

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I know that there'll be some variables here, namely time period and such, but what if the British had their own long range escort fighter? Naturally, it can't really be a Spitfire or a Hurricane since they're too short legged early war (and Spitfire for most of the war). But, from say 39-42, 42-45, what would a single seat, long range high performance escort fighter be like? The biggest thing as far as spec is enough fuel internally to have a 700-800 mile range, and the ability to use drop tanks. It also has to be heavily armed for the period (which from 42-45 basically means 4x20mm cannons), and be a great dogfighter per tactics of the period. This will address one of the few shortcomings of the P-51, given that it was a bit heavy due to being built to outdated USAAF load requirements (largely resolved with the H variant, but that doesn't really count here).

So I'll open the floor to the forum members to discuss.
There are a number of threads on this. Some quite lengthy. Some of it can be boiled down to year/s and two time periods are nowhere near enough. Using the Spitfire to illustrate the problems.
1939 two pitch props are being fitted, fixed pitch props are being used as mess decorations. (or going into wood stoves) But even the two pitch props don't allow full power, or as full as a Merlin III will let you use on 87 octane fuel, for take-off. Work is being done on landing fields. AS to combat. A Spitfire I with 2 pitch prop takes about 3 minutes longer to climb to 20,000ft than when using a constant speed prop and that is using the standard fuel. Add 300-450lbs of fuel and self sealing tanks at your peril. Very little 100 octane fuel, they know it is coming. very limited armor and very limited self sealing tanks.
1940. more use of constant speed props and in June the two pitch props are gone from service squadrons (OTUs may be different). Limited self-sealing tanks. armor and BP glass in most cases. Merin XII engines show up in mid year, 100 octane fuel is pretty much standard, at least for most of Britain. Air fields are still being worked on but they are expanding.
Two speed superchargers (Merlin XX) are in production but you have to fight BC for them, Hurricanes get them in Sept to keep them competitive with the 109E-3/4. cannon are trialed (not well)
1941 Merlin 45s show up. Propeller situation is resolved, ignore from now on. 100 octane fuel is standard in more places, last time we need to mention it. Merlin XX is going into bombers, Beaufighter IIs and Hurricane IIs 109s not only get new engines but 109Fs show up. During the year 12 gun Hurricanes show up and a few Typhoons. Spitfires get 20mm guns (with 60rpg) and Hurricanes get 20mm guns near the end (?) with 90rpg.

that is a very brief over view as to the propeller, fuel, engine, protection and armament situation.

There were attempts to solve the fuel problem
spitffire-p9565-mk-i-longrange-jpg.jpg

Spit II with Merlin XII engine. It was high drag (tank was fixed) and hurt climb. Internal fuel would solve drag but not do a lot for the decrease in climb. It held 40 gallons which was not enough for even 600 miles range (you can't putz about flying at 210-220mph while escorting in enemy airspace).

Test aircraft was 2 minutes and 48 seconds slower to 20,000ft than the 1st Spit IIA tested at Boscombe Down. It took 4 mins 30 seconds more to go from zero to 25,000ft.
Climb at 25,000ft was 1050fpm while the standard IIA could climb at 1600fpm.
Even with a a better tank (internal) that is a significant handicap.
 
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BarnOwlLover

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Maybe I should also note that long range bombing on German soil wasn't the biggest priority in 1939-42 for the British. However, when the USAAF entered the fray and Britain's own 4 engine heavies seriously came online in 1942 onwards, a British built day fighter that could do escort missions would've been useful. Interestingly, (just for stats) the Hawker Typhoon had pretty long range when fitted with drop tanks, as did the Tempest and Fury/Sea Fury. However, the Typhoon was intended to be an interceptor (and ended up only good at that at low/medium altitudes), and the Tempests and Sea Fury weren't insanely good at very high altitudes, either.

There's still the Spitfire, but in all it's variants, it was basically a short-legged interceptor, irrespective of if the Merlin or Griffon was used. Even the Spiteful had longer range (560 miles internal fuel, just under 1400 miles with drop tanks).

Maybe a "baby" Tempest or Fury could foot the bill for a British-built single engine escort fighter. We know that the Fury/Sea Fury was the result of Sydney Camm and the RAF wanting a lightweight, general purpose version of the Tempest. However, light was a relative term, since it was designed for the same engine classes as the Tempest (Sabre, Centaurus, Griffon), and the land-based Furies still had a take off weight in excess of 5 tons. And that's considering that the Tempest and Fury/Sea Fury were great handling and very maneuverable for their size.

But, maybe a "baby", lightweight Tempest/Fury powered by a Merlin 60 series or later engine could foot the bill, or a Merlin-powered Spiteful type aircraft with similar fuel capacity (internal and external).

Ironically, the Focke-Wulf Ta-152B and H models were designed to be bomber escorts since they had increased internal fuel tankage (750 mile range) and the B probably could take drop tanks (the Hs that were built didn't have hardpoints for drop tanks to my knowledge). But, one, the Ta-152 had a 2000 hp class engine to deal with the increased weight. And, very (IMO) ironically, they came in 1945, with only the B prototypes and a few H's getting built--and above all, escort fighters were out of place in 1945 for the Germans. Though the increased range of the Ta-152 would've helped with patrols and staying in the fight when they got airborne. The range of the Tempest was similarly used against V-1 flying bombs and other patrol missions.
 

tomo pauk

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1940. more use of constant speed props and in June the two pitch props are gone from service squadrons (OTUs may be different). Limited self-sealing tanks. armor and BP glass in most cases. Merin XII engines show up in mid year, 100 octane fuel is pretty much standard, at least for most of Britain. Air fields are still being worked on but they are expanding.
Two speed superchargers (Merlin XX) are in production but you have to fight BC for them, Hurricanes get them in Sept to keep them competitive with the 109E-3/4. cannon are trialed (not well)

The 2-speed supercharged Merlin X was from 1939? It provides a bit better power than the Merlin III at all altitudes.
Fighter Command actually needs to fight themselves to get the Merlin XX - there was zero Merlin XXs on bombers? Main users were Hurricanes, Defiants and Beaufighters.

Test aircraft was 2 minutes and 48 seconds slower to 20,000ft than the 1st Spit IIA tested at Boscombe Down. It took 4 mins 30 seconds more to go from zero to 25,000ft.
Climb at 25,000ft was 1050fpm while the standard IIA could climb at 1600fpm.
Even with a a better tank (internal) that is a significant handicap.

Having top-tier engines improves the speed and RoC, and Spitfire was not getting these until second half of 1942.
OTOH, it is to be expected that escort aircraft laden with fuel can't climb as fast as the point-defence siblings, if both were powered by the same engines.
 

tomo pauk

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Interestingly, (just for stats) the Hawker Typhoon had pretty long range when fitted with drop tanks, as did the Tempest and Fury/Sea Fury. However, the Typhoon was intended to be an interceptor (and ended up only good at that at low/medium altitudes), and the Tempests and Sea Fury weren't insanely good at very high altitudes, either.

Typhoon was pretty short-ranged A/C, with drop tanks the range was 860-1000 miles. Combat range is 35% of that?
Tempest was better, due to less drag and a bit more internal fuel. With the modifications from second half of 1944 (introduction of another leading-edge tank) and now with 2 x 90 imp gals, it was excellent with almost 1800 mile range. Yes, that is too late,W Allies already have the foothold in France by then.
Tempest V was better than the Fw 190As, that were the main threats to the WAllied day bombers. Tempest II was a bit better, the Sea Fury was again better than the Tempest II.
 

Shortround6

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The 2-speed supercharged Merlin X was from 1939? It provides a bit better power than the Merlin III at all altitudes.
Fighter Command actually needs to fight themselves to get the Merlin XX - there was zero Merlin XXs on bombers? Main users were Hurricanes, Defiants and Beaufighters.
Merlin X engines in the Whitley's and in a few Halifax's. (around 75) and about 400 Wellingtons (Wellington II first flew in March 1939)
You may be right on the Merlin XX until 1941.


Having top-tier engines improves the speed and RoC, and Spitfire was not getting these until second half of 1942.
OTOH, it is to be expected that escort aircraft laden with fuel can't climb as fast as the point-defence siblings, if both were powered by the same engines.

Spitfire was getting the best single stage single speed engines. Nobody had the two stage engines until the 2nd half of 1942. Or very few, there were only a bit over 60 high altitude Wellingtons built.
The original poster wants long range and maneuverability, not going to get with the original engines and fuel.
A Merlin 45 100 octane would give about 300-350hp for take-off over a Merlin III with 87 octane, and weighed within 10lbs. If you can't make a Spitfire V work as an escort fighter in late 1941 or beginning of 1942 then there isn't much hope for anything any earlier.
The Spitifre V can probably take on a late 109E, 109F may be a harder.
 

Shortround6

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. Interestingly, (just for stats) the Hawker Typhoon had pretty long range when fitted with drop tanks, as did the Tempest and Fury/Sea Fury
This has been gone over in the earlier threads.
Your combat radius depends on how much fuel you have in the tanks when you drop them.
Now out of the fuel in the internal tanks you need to fight for 15-20 minutes, use a high speed cruise to get back to the channel (no most economical unless you want to be posted as a kill marking on a Luftwaffe plane) and at least 30 minutes of fuel once you cross the British coast while looking for your own or an alternative landing field. Typhoons tended to go through the fuel pretty quick if you were pushing their engines.

Speeding 15 minutes at combat rating was worth 180 miles at max weak mixture or 225 miles at most economical.
 

tomo pauk

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Spitfire was getting the best single stage single speed engines. Nobody had the two stage engines until the 2nd half of 1942. Or very few, there were only a bit over 60 high altitude Wellingtons built.
The original poster wants long range and maneuverability, not going to get with the original engines and fuel.

Best single-speed S/Ced engines were worse than best 2-speed engines.

Merlin X does 1010 HP at 17500 ft (per the Whitley V datasheet), 87 oct fuel. That compares favorably vs. the early DB 601A doing ~860 HP there, or even vs. the later DB 601A doing ~900 HP there. Original poster will get speed, range, and firepower powerful enough to deal with enemy fighters, with non-original engines helping to cater for increased weight.

A Merlin 45 100 octane would give about 300-350hp for take-off over a Merlin III with 87 octane, and weighed within 10lbs. If you can't make a Spitfire V work as an escort fighter in late 1941 or beginning of 1942 then there isn't much hope for anything any earlier.
The Spitifre V can probably take on a late 109E, 109F may be a harder.

I haven't suggested the Spitfire V anywhere in this thread.
 

BarnOwlLover

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I wonder if I should re-word/refocus on "endurance" rather than "range". Range is of course the distance a plane can fly on fuel under whatever specified conditions. Endurance is how long it can fly under those same conditions, which accounts for take off, cruse, a certain amount of combat or loiter time, return and landing.

This also might lead me to rethink some of the stuff I was looking at for my prospective fighter in that thread. Namely in that case that increased internal fuel does give more options (partial fuel for interceptor missions, better carriage of bombs/rockets/ similar stores for short range ground attack/close support missions, etc). This can open up possibilities for discussion here, too. Especially since I'm basically asking for not extending the range of say a Spitfire, but basically a clean sheet of paper design.
 

tomo pauk

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I wonder if I should re-word/refocus on "endurance" rather than "range". Range is of course the distance a plane can fly on fuel under whatever specified conditions. Endurance is how long it can fly under those same conditions, which accounts for take off, cruse, a certain amount of combat or loiter time, return and landing.
Range is about source and destination. If the destination can't be reached, the escort fighter is of dubious utility.
Endurance can be improved by flying as slow and as low as possible, Japanese did that often above Pacific. Will not work in the contested airspace the RAF LR fighter is supposed to operate, since that way the enemy has the upper hand when air combat starts, and Germans were fielding AA guns by many thousands.
There were good reasons for the USAAF to specify ~310 mph TAS (at 25000 ft) for the escort fighters.

Namely in that case that increased internal fuel does give more options (partial fuel for interceptor missions, better carriage of bombs/rockets/ similar stores for short range ground attack/close support missions, etc).

Increased internal fuel is indeed the major thing. It helped Bf 110, Zero and Mustang to be actual long-range fighters.

Especially since I'm basically asking for not extending the range of say a Spitfire, but basically a clean sheet of paper design.

I've already extended the range of Spitfires ;)
The clean-sheet design from De Havilland would've been interesting, talk a Merlin-powered fighter with a wooden airframe, improvements to the engine breathing (carb, exhausts), LE radiators and enough fuel.
 

PAT303

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Spit II with Merlin XII engine. It was high drag (tank was fixed) and hurt climb. Internal fuel would solve drag but not do a lot for the decrease in climb. It held 40 gallons which was not enough for even 600 miles range (you can't putz about flying at 210-220mph while escorting in enemy airspace).

Test aircraft was 2 minutes and 48 seconds slower to 20,000ft than the 1st Spit IIA tested at Boscombe Down. It took 4 mins 30 seconds more to go from zero to 25,000ft.
Climb at 25,000ft was 1050fpm while the standard IIA could climb at 1600fpm.
Even with a a better tank (internal) that is a significant handicap.
Climb doesn't matter because it'll already be at altitude when it enters enemy airspace, the P51 couldn't climb nor could any other fighter when loaded with fuel.
 

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