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

[ThomasP]

Approximate increased weights and fuel load/range decrease for A6M2 already calculated.

"How bad would a Euro-spec A6M Zero be?"

Note that I used .5" thickness and .96 lb per ft2 of wall area for the weight of the SSFT. This is the CIMA type produced by FPT (a subsidiary of Airspeed) beginning in 1939 for refit to the Battle, and used for nearly all later refits and new production combat aircraft. For the UK this is the good stuff.

 

[PAT303]

There is no practical engineering reason why various improvements could not be implemented, including more powerful engines, armour, SSFT, more efficient armament, etc. The only reason the Japanese did not implement more of these improvements during (or earlier in) the war was due to the pressures of war-time manufacturing. I think it is safe to assume that if the Germans had adopted the A6M airframe they would have introduced the needed improvements.

But then it wouldn't be a Zero, the Zero got all it's performance by not having all of the equipment the European/American/Soviet fighters had, like I posted on the other thread the British could have got a MkIV PR Spit, put the guns back in with aux tanks and hey presto a Euro Zero, but they wanted pilot protection, workable radio's and survivability. People seem to ignore the fact the Zero got it's range by having lots of fuel in unprotected tanks and flying low and slow over open ocean or impenetrable jungle, none of that will work over airspace defended by an integrated air defence network which is exactly what was in place on both sides of the channel in 1940 onwards. Lets go further into this, if the Americans or RAF had Merlin engined P51's in 1941-42 they wouldn't have made it to Berlin either, the Luftwaffe fighter groups across the channel were every bit the equal of the RAF with better aircraft, trying to get to Berlin in a fuel laden P51 was suicide, the combination of 190's low down and 109's above means you have no advantage anywhere, and if you did fight your way through they are all waiting for you on the way back fueled up and armed with hours of time to position themselves to hit you, the reason I would have Spits with the range to go the the Ruhr only until P51's and P47's numbers are built up, any further and the balance swings into the Luftwaffe's favour.

 

[Howard Gibson]

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.

Your escort fighter has to use 1938 technology, it must have large, heavy gas tanks, and it must be superior to the Bf109E in combat. 1938 means you have had time to manufacture lots of your escort aircraft. The Bf109E was a world class fighter aircraft that the lightweight, short ranged Hurricanes and Spitfires had difficulty with.

The P-51 Mustang was a successful escort fighter because it used the advanced laminar flow wings, 100/130 octane fuel, and two-stage superchargers. The German's failure to develop this stuff more than made up for the Mustang's large, heavy fuel tanks.

 

[Shortround6]

Things are somewhat relative.
An Allison Mustang went about 6900-7050lbs empty equipped. Put in a pilot, oil, ammo and a bit over 100US gallons of fuel and you had a over 8000lb airplane, Yes you could put in another 450lbs of fuel and a bit more oil but it wasn't so much the large heavy fuel tanks.

But yes, you can't have a wonder fighter in squadron (or group ) service in 1940-41 if you only fly the prototype in 1940. You need to have the thing entering production in early 1939 at the latest, and sometime in 1938 is much more realistic.
1938-39 engines were closer to 1000hp than they were to 1200hp. The British get the 1200hp engines in the middle of 1940, So do the Germans,, The US was still working on the 1040-1090hp engine for production, the Zero had 950hp at altitude.

 

[Admiral Beez]

How about the Westland Whirlwind? Increase internal fuel, add external tanks, add bypass valves so that either engine can use any fuel tank. We also need more internal ammunition, which means seepentine belts rather than drums for the four 20mm cannons. What do we think of a large central drop tank vs. or along with drop tanks under each wing? Can the Peregrine be supercharged or tuned for efficient high altitude use?

 

[tomo pauk]

1938-39 engines were closer to 1000hp than they were to 1200hp. The British get the 1200hp engines in the middle of 1940, So do the Germans,, The US was still working on the 1040-1090hp engine for production, the Zero had 950hp at altitude.

British have the 1300 HP Merlin III by some time time of 1939, an certainly in the beginning of 1940.
Americans have the R-2600-3 (1600 HP down low, 1275 HP @2300 rpm at 12000 ft max continuous; on A-20B it was 1400 HP @ 2400 rpm at 10800 mil power) in 1939. From Wikipedia entry about the B-23, that was powered by the -3:

The first B-23 flew on July 27, 1939 with the production series of 38 B-23s manufactured between July 1939 and September 1940.

Americans do get 1200 HP engines in form of R-1830 and R-1820 in some time of 1939, and again certainly in 1940. They also can count on the help of turbochargers, imperfect as they are back then. From Joe Baugher's site:
More-powerful R-1820-51 engines were fitted which delivered a maximum power of 1200 hp for takeoff and 900 hp at 25,000 feet.
and:
All 39 of the B-17Bs were delivered to the USAAC between July 29, 1939 and March 30, 1940.

The 1400 HP R-2180 engine was sold in Japan together with the DC-4E in late 1939, more than a year after the 1st flight of the A/C.

Technology was not a problem, doctrine was.

 

[wuzak]

How about the Westland Whirlwind? Increase internal fuel, add external tanks, add bypass valves so that either engine can use any fuel tank. We also need more internal ammunition, which means seepentine belts rather than drums for the four 20mm cannons. What do we think of a large central drop tank vs. or along with drop tanks under each wing? Can the Peregrine be supercharged or tuned for efficient high altitude use?

Yes, a higher altitude supercharger (changed gearing). or a two speed unit could have been fitted.

The 2 speed option would increase the engine length, possibly requiring extensive changes to the airframe. It would allow improved altitude performance, while maintaining lower altitude performance.

The Peregrine could have been fitted with a 2-stage supercharger, or paired with a turbocharger, but this would have required a lot of modification to the airframe - would have been better to redesign the Whirlwind so that it could accept Merlins.

 

[ThomasP]

sigh

 

[PAT303]

We also need more internal ammunition, which means seepentine belts rather than drums for the four 20mm cannons.

Another really good point, it's pointless trying to gain air superiority over a large area with only 9 seconds of cannon ammunition, you either stick to RCMG's or develope belt feed cannons, as well as internal tanks, two stage two speed engines, gyro gunsights all 2-3 years before it actually happened.

 

[Shortround6]

British have the 1300 HP Merlin III by some time time of 1939, an certainly in the beginning of 1940.

We do have to be careful about what altitudes we are talking about.
Yes once the British got 100 octane fuel they could get 1310hp out of a Merlin.
2 problems,
1, that was at 9000ft. at 16,250ft it was still a 1030hp engine, even with 100 octane fuel. Official up-rating was March of 1940. Obvouly they had doing testing much earlier.
2. The Climb rating took a while to upgraded. They allowed 2850rpm when climbing for combat conditions in the summer of 1940. RR lists 2600rpm and 6 1/4lbs of boost for 30 minute climb. The 2850rpm limit below 20,000ft and 3000rpm above 20,000ft have the same limitations as the 12lbs of boost. Every use of these climb ratings must be reported upon landing and an entry made in the engine log book.
Take-off power rating was never changed.
The Merlin XII was given a slightly higher supercharger gear. What was more important was that the take-off rating was upgraded to 1175hp at 12 1/2lbs boost and the 30 minute climb rating was 2850rpm and 9lbs of boost for 30 minutes. 12lbs of boost in combat gave 1280hp at 10,500ft.
This engine was going into service about the same time as the Merlin III was allowed to use the ratings listed above except the Merlin XII was allowed to use the 2850rpm and 9lbs climb without having to report upon landing and making entries in the engine log book.

Americans do get 1200 HP engines in form of R-1830 and R-1820 in some time of 1939, and again certainly in 1940. They also can count on the help of turbochargers, imperfect as they are back then. From Joe Baugher's site:

there were a lot of changes between 1939 and 1940. There were certainly things going on in the test houses but actual 1200hp engines in service were pretty rare in 1939.
Wright started delivery of 1200hp R-1820s in March of 1939. They had started delivering 1100hp R-1820s in Jan 1937. Please note that the British and the Belgians only got the 1100hp engines in there Buffaloes.
For the Hawk 75s you had the
H75A-1 R-1830=950hp for T-0, 900hp at 12,000ft
H75A-2 R-1830=1050hp for T-0,
H75A-3 R-1830= 1200hp for T-0, 1,050hp at 7,500ft.
H75A-4 R-1820= 1200hp for T-0, 1,100hp at 5,100ft, 1000hp at 15,000ft.
H75A-5 R-1820= 1100hp for T-0.
H75A-6 R-1830= 1200hp for T-0. P & R says 1050hp using 87 octane fuel ?
H75A-7 R-1830= 1200hp for T-0. P & R says 1050hp using 87 octane fuel
H75A-8 R-1820= 1200hp for T-0, as the H75-A4.
H75A-9 R-1820= 1200hp for T-0, as the H75-A4.

And since these radial engine Hawks showed about 20-22% increase in drag over the P-40 with the Allison what are these 1200hp engines at sea level actually getting you?
Same for the R-2600. 1400 HP @ 2400 rpm at 10800.
Once we figure in the extra drag and the difference in altitude the R-2600 is giving us just about 22% more power than the C-15 long nose Allison (not counting exhaust thrust)

 

[Shortround6]

Another really good point, it's pointless trying to gain air superiority over a large area with only 9 seconds of cannon ammunition, you either stick to RCMG's or develope belt feed cannons, as well as internal tanks, two stage two speed engines, gyro gunsights all 2-3 years before it actually happened.

9 seconds is generous. If the cannon fire at 540rpm you only get about 7 seconds. 9 seconds would give a cycle rate of 400rpm.

 

[GrauGeist]

How about the Westland Whirlwind? Increase internal fuel, add external tanks, add bypass valves so that either engine can use any fuel tank. We also need more internal ammunition, which means seepentine belts rather than drums for the four 20mm cannons. What do we think of a large central drop tank vs. or along with drop tanks under each wing? Can the Peregrine be supercharged or tuned for efficient high altitude use?

There were several twins that could have been developed if the Air Ministry foreseen the need for a long range escort and the submissions for F.11/37 would have been the best candidates.
In the late 30's, twin "heavy fighters" were seen as a solution and the British did have several candidates that may have proved useful if they hadn't been kept on the back burner or cancelled.

The two that looked promising were:
Gloster G.39 "Reaper"
Boulton Paul P.92

 

[Shortround6]

How about the Westland Whirlwind? Increase internal fuel, add external tanks, add bypass valves so that either engine can use any fuel tank. We also need more internal ammunition, which means seepentine belts rather than drums for the four 20mm cannons. What do we think of a large central drop tank vs. or along with drop tanks under each wing? Can the Peregrine be supercharged or tuned for efficient high altitude use?

The Whirlwind used a smaller wing than the Hurricane. There were a number of things that could have been done to improve it. However trying to turn it into a long range fighter was a real waste of effort.
MK I Spit on test (with two 20mm guns and four .303s) was able to do 348mph at 15,000ft using Merlin IIIs on 6lbs of boost, around 1030hp. The Whirlwind needed 1770hp to 12mph faster?
You have way to much drag to get this to work. Needing 50-60% more fuel than Spitfire is not going to solve the problem.

 

[Macandy]

Pretty clueless until some Brit told them what to build eh?

Nope, US production engineering and manufacturing was at least a generation ahead of the rest of the world in 1941.

 

[Macandy]

I'm pretty sure we all know this and the myth of the 'mericans showing the British how mass production works has been debunk numerous times but alas the rumour still persists.

Hint, Ford was an American company using the best US practice.

 

[pbehn]

Nope, US production engineering and manufacturing was at least a generation ahead of the rest of the world in 1941.

That is two years late, the war started in 1939, which is why you had sod all except a flag to wave, far from a generation ahead you were 2years behind and still made rubbish like the P-39.

 

[Macandy]

That is two years late, the war started in 1939, which is why you had sod all except a flag to wave, far from a generation ahead you were 2years behind and still made rubbish like the P-39.

Wrong again… one of the finest piston engined fighters of all time, the F4U Corsair? Design spec let in 1938 and manufactured using techniques the much vaunted Germans never even though of.
And then of course we have the B-29, dates from 1939 - incorporating technology, mass produced technology, that no other combatant ever successfully developed, let alone mass produced.

 

[Macandy]

Your escort fighter has to use 1938 technology, it must have large, heavy gas tanks, and it must be superior to the Bf109E in combat. 1938 means you have had time to manufacture lots of your escort aircraft. The Bf109E was a world class fighter aircraft that the lightweight, short ranged Hurricanes and Spitfires had difficulty with.

The P-51 Mustang was a successful escort fighter because it used the advanced laminar flow wings, 100/130 octane fuel, and two-stage superchargers. The German's failure to develop this stuff more than made up for the Mustang's large, heavy fuel tanks.

And always forgotten that until it burned off a fair chunk of its huge fuel load, a Mustang was a dangerous beast that killed plenty of unwary pilots in take off accidents.

 

[pbehn]

And always forgotten that until it burned off a fair chunk of its huge fuel load, a Mustang was a dangerous beast that killed plenty of unwary pilots in take off accidents.

Was it? Where did you make that up? I mean read? I knew the P-39 was rubbish, do we add the P-51 to this lamentable list of tripe?

 

[Shortround6]

A lot of claims being made.
On both sides.

US army may have been guilty on the P-51. The manual says to burn off 30 gallons out of the rear tank after take off. Then switch to the drop tanks if fitted. Then switch to the wing tanks ( keeping the plane in balance) and then go back to rear tank for the reserve and landing.
This is a post war manual so they had plenty of time to figure it out.

Flying high powered fighters with less than stellar stall behavior was always tricky.