Escort Fighter Performance Comparison

[FLYBOYJ]

Zipper730 said:
For some reason, I thought the Tempest was operational earlier actually. I am interested about the low-speed handling characteristics of the Tempest against the P-51 regardless (merely out of curiosity).

Technically, I was thinking of allied forces. Regardless, it seemed the Axis powers largely had developed escort capabilities as time went on.

What is "low speed" the landing speed of a Tempest was 110 MPH, a low speed handling competition between those two is like a parking competition for F1 cars. The German part of the Axis scaled back manufacture of machines that needed daylight escort from 1943, Attacks on UK were done at night.

Actually I think what is meant is "Maneuvering Speed" AKA as "Va." Maneuvering speed for a P-51 is shown to be around 265 MPH.

 

[Zipper730]

What is "low speed" the landing speed of a Tempest was 110 MPH

Maneuvering speed.

Actually I think what is meant is "Maneuvering Speed" AKA as "Va." Maneuvering speed for a P-51 is shown to be around 265 MPH.

Correct: If I recall, a rough approximation is the stall-speed x square-root of rated g-load, with the exact calculation being: V = sqrt (2L/((CL)(ρ)(A)

Do you (or drgondog ) have these figures for the two aircraft?

 

[GregP]

Speeds are mph I.A.S.:

Looking at the Tempest V pilot manual, the approach speed, gear up, flaps up in 120 mph; 100 mph with flaps down. It says, "Do not turn below 135 - 140 mph. Max div speed at altitude (35,000 ft) is 340 mph, up to 540 mph (10,000 ft).

There is no V-g diagram, so there is no maneuvering speed listed. Perhaps at ww2aircraftperformance.

 

[Zipper730]

Speeds are mph I.A.S.

From what I recall, the Tempest doesn't seem to have (based on the pilot's manual) any correction at the lower end of the speed range. Not sure about the Spitfire.

There is no V-g diagram, so there is no maneuvering speed listed.

The British seem to miss stuff in manuals that we usually put in. The F4U had a V-N diagram

 

[GregP]

From what I recall, the Tempest doesn't seem to have (based on the pilot's manual) any correction at the lower end of the speed range. Not sure about the Spitfire.
The British seem to miss stuff in manuals that we usually put in. The F4U had a V-N diagram

You mean position correction for airspeed? The stall speed, gear down was 75 mph and 85 mph gear up. That's I.A.S. But, with the caveat to not turn below 135 - 140 mph, I'd say the stall is not gentle. I can't think of another aircraft that has bad handling 50 mph above stall other than an F-4 Phantom. It doesn't handle worth a crap below 350 knots and turns below that speed are pretty much with rudder only.

Seems like the Tempest may be a kindred spirit that likes thing a bit faster than other contemporary fighters. The Spitfire and Hurricane handled great around stall.

 

[Jabberwocky]

You mean position correction for airspeed? The stall speed, gear down was 75 mph and 85 mph gear up. That's I.A.S. But, with the caveat to not turn below 135 - 140 mph, I'd say the stall is not gentle. I can't think of another aircraft that has bad handling 50 mph above stall

Maybe not 50 mph above, but I recall reading somewhere that early Ki-44-Is had a really vicious accelerated stall, hence the need to fit the automated combat maneuvering flaps after the first few production examples were delivered. Japanese pilots also expressed dislike for the Ki-44s oversensitive elevators, which had a tendency to put the aircraft into a snap stall if handled roughly. As a lot of pilots transitioned from the Ki-43, which had very nicely balanced controls, this may have exacerbated the problem.

 

[Howard Gibson]

How about we not re-run the war except in the "what if: category, which is rather notorious for having no correct answers to any questions.?

What happens if you design a point interceptor and I design a long range escort fighter with both of us using equivalent technology? My aeroplane will have larger fuel tanks, and I will set up the aerodynamics to provide efficient high speed cruise. Your aeroplane will be smaller and lighter, and it will be optimised for manoeuvrability, acceleration, climb and top speed. My aeroplane will be faster in a dive. You do need heavier armament to knock down my bombers, which increases your weight a bit.

I am facing the classic military problem of fighting at the end of extended communications. I cannot just say I am going to design an escort fighter that will be superior to whatever it is you have, unless I have some technological and/or logistical advantage, like high octane fuel, turbochargers, and an effective training program for my new pilots.

 

[pbehn]

What happens if you design a point interceptor and I design a long range escort fighter with both of us using equivalent technology? My aeroplane will have larger fuel tanks, and I will set up the aerodynamics to provide efficient high speed cruise. Your aeroplane will be smaller and lighter, and it will be optimised for manoeuvrability, acceleration, climb and top speed. My aeroplane will be faster in a dive. You do need heavier armament to knock down my bombers, which increases your weight a bit.

I am facing the classic military problem of fighting at the end of extended communications. I cannot just say I am going to design an escort fighter that will be superior to whatever it is you have, unless I have some technological and/or logistical advantage, like high octane fuel, turbochargers, and an effective training program for my new pilots.

Who designed a long range escort in WW2? Certainly not the USA or British. They adapted designs for the role that were originally designed for something else.

 

[Deleted member 68059]

The Germans had a terrible time using twin-engined, two-seater fighters as daylight bomber escorts. Would the British have failed as badly had they sent the Mosquito fighter variant as a daylight bomber escort?

"
The exchange ratio of the Bf-110 was positive at the BoB as well. "common knowledge" indeed appears to be a "common myth". Also factoring in that the Bf-110c was the worlds most effective bomber interceptor platform in 1940 may explain why the exchange ratio was that positive. From known losses and kills such as analysed by danish author
Christer Bergström, Luftskrid over kanalen (2006)


* Spitfire: 550 confirmable kills 329 losses -exchange ratio is 1.7: 1
* Hurricane: 750 confirmable kills 603 losses -exchange ratio 1.2: 1
* Bf 109 780 confirmable kills 534 losses – exchange ratio 1.5: 1
* Bf 110 340 confirmable kills 196 losses – exchange ratio 1.7: 1

The Bf-110 suffered from a negative exchange ratio only when forced to close escort orders in late august and early september 1940. Before and after this time (when these orders were lifted again), the exchange rate was very positive in favour of the Bf-110 as was the mean average from august to oct.
"

bf110 exchange ratio

It's common knowledge that the bf110 performed poorly during the Battle of Britain, but it seems to have done much better over Dunkirk against British fighters. Looking in 'Battle of France, Then and Now', the bf110 had a slightly positive exchange ratio against Hurricanes and Spitfires. There...

ww2aircraft.net

After having recently got copies of the British Air Intelligence files on the Me110, I have changed my mind about it, and now view it as thoroughly under-rated.

The British found it had extremely surprising manuverability, very pleasant flight charactistics, combined with heavy firepower, superb pilot vision
and very good climb/zoom.

I had previously assumed it was a deadweight slug, based on "common wisdom", it seems that it was a lot better than it is usually given credit for. Of course
making it viable against single engine opposition requires very specific tactics...

 

[Geoffrey Sinclair]

From known losses and kills such as analysed by danish author Christer Bergström, Luftskrid over kanalen (2006)

* Spitfire: 550 confirmable kills 329 losses -exchange ratio is 1.7: 1
* Hurricane: 750 confirmable kills 603 losses -exchange ratio 1.2: 1
* Bf 109 780 confirmable kills 534 losses – exchange ratio 1.5: 1
* Bf 110 340 confirmable kills 196 losses – exchange ratio 1.7: 1

The Bf-110 suffered from a negative exchange ratio only when forced to close escort orders in late august and early september 1940.

Williamson Murray, Luftwaffe strength 28 June 1940 1,107 Bf109 to 357 Bf110, or about 3 to 1 Bf19 to Bf110

Wood and Dempster, 10 August 1940, Bf109 1,101 establishment, 934 strength, 805 serviceable, Bf110 301 / 289 / 224, or over 3 to 1 Bf109 to Bf110.

So Bergstrom reports the Bf110 force scored about 1 confirmed kill for each of its initial strength, the Bf109 about 0.8. Then when you factor in multi engine multi crew aircraft generate fewer sorties per aircraft than single engine single seaters, and the close escort tactics, Bergstrom is reporting the Bf110 was a much better fighter than the Bf109, longer ranged, scoring as high as maybe 50% more confirmed kills per sortie over the course of the Battle of Britain, if allowed to optimise its tactics.

The Battle of Britain Then and Now says Fighter Command had 1,026 total losses for the Battle, with 798 due to enemy action and 40 more unknown, of the enemy action losses 672 are attributed to enemy fighters or enemy aircraft. Bergstrom has 1,120 confirmed kills by Luftwaffe fighters, which means up to another 450 non RAF Fighter Command aircraft are confirmed shot down, which would be mostly from Bomber Command and Coastal Command. Bergstrom says over the Battle of Britain the Luftwaffe fighters shot down 3 Fighter Command to 2 other RAF command aircraft. Bomber Command lost 382 aircraft in the period to all causes, 103 by day, 279 by night, 187 of the losses came down on British territory. Using Boiten's Nachtjagd War Diaries and the Bomber Command Losses series 15 day and 23 night losses are due to Luftwaffe fighters, 14 more losses are to unknown causes.

That still leaves hundreds from Coastal Command to make up the numbers, total all causes losses on operations for all of 1940 were 310, few are logged as lost to fighters, see Coastal Command Losses by Ross McNeill.

The old Luftwaffe kill claims list I have for the Battle of Britain has ZG26 and ZG76 but is missing ZG2, the ZG units logging 231 claims, some of which were disallowed, the JG units 1,894, again including some that were disallowed. Bergstrom more than halves the Bf109 claims, but must have several hundred more claims by Bf110 that the old list I have is missing.

Williamson Murray, losses to end September 1940, Bf109 398 enemy, 79 ops, 41 non ops, Bf110 214 enemy, 9 ops, 12 non ops

The Battle of Britain Then and Now listing, 10 July to 31 October has the total all causes losses on operations as Spitfire 353, Hurricane 569, Bf109 600, Bf110 248.

Bergstrom reports, July to October, Spitfire 394, Hurricane 603, Bf109 534, Bf110 196

Luftwaffe Quartermaster reports as translated by the RAF, July to October Bf109 600, Bf110 235, plus 18 night fighters.

Williamson Murray, Luftwaffe, table IX says in the July to September period the Luftwaffe single engined fighter units lost 47% of their original strength, the twin engined units 66%. For May and June 1940 Murray reports the Luftwaffe single engined fighter units lost 19% of their original strength, the twin engined units 30%, for May to September, single engined fighter units lost 57% of their original strength, the twin engined units 97%,

Bergstrom's total of confirmed kills by Luftwaffe fighters, at 1,120, is hundreds more than can be confirmed by RAF records and post war investigations, his fighter losses for the RAF higher and Luftwaffe lower than the air force records.

The main reported Bf110 failing was poor acceleration, which would be a big problem on close escort sorties.

 

[Zipper730]

D Deleted member 68059, I remember hearing Capt. Eric M. Brown talking about the aircraft doing quite well when it wasn't tied close to the bombers it was escorting.

 

[Zipper730]

This is pretty interesting

I transcribed all the numbers and, also rewrote a few terms (permanent fuel was obviously internal fuel). I reposted this because I inadvertently made a typo the first time.

The figures for the modified Tempest Mk.II/V are quite interesting, particularly the ability to squeeze around 25-30 gallons into the aircraft, though it would have still come up short relative to the P-51B/C.

 

[Deleted member 68059]

Will post some snippets on the British intellgence files on Me110 evaluation later today.

 

[Stig1207]

danish author
Christer Bergström,

Swedish actually; I know we look and sound much the same, but still

 

[Deleted member 68059]

Swedish actually; I know we look and sound much the same, but still

Sorry I just copy pasted that text from the linked prevous post by someone else on this forum...

 

[drgondog]

This is pretty interesting
View attachment 665818

I transcribed all the numbers and, also rewrote a few terms (permanent fuel was obviously internal fuel).
View attachment 665819

The figures for the Tempest are quite interesting though it obviously wouldn't measure up to the P-51B/C

Interesting contrast between pre-P-51B and Tempest Range figures. The N-73 through P-51A (internal fuel only at 180gal US) had a straight line range w/no reserve at 10K of about 1050mi. If all the RAF data is in Imperial Gallons, the Tempest II and V straight line ranges of 740 and 790 respectively for 194gal US and 192gal US is 30% less than Allison engined Mustangs with 7% more fuel. The P-51B with no fuselage tank had very slightly less straight line range at 1025mi with 4 gallons more than P-51A

 

[Geoffrey Sinclair]

This is pretty interesting
View attachment 665818
I transcribed all the numbers and, also rewrote a few terms (permanent fuel was obviously internal fuel).
View attachment 665819

The transcription for the Spitfire IX (cut away fuselage as modified in the U.K.), second and third lines should read 96+62?

The next page in Air 19/286 is interesting, it dates the document to 7 September 1944 and states,

"3. The following progamme has been arranged:-
(i) Spitfire IX (now in production). 800 sets of tanks have been ordered for retrospective fitting and production of these tanks should commence in about 3 months' time. The modification will comprise replacing the existing 85 gallon main fuselage tank by a 96 gallon tank and fitting a 72 gallon self sealed tank in the fuselage behind the pilot.

(ii) Spitfire IX (cut away fuselage). This aircraft comes into production in about 4 months' time and it is hoped to embody the 96 gallon main tank and a 62 gallon rear fuselage tank in the production line from the outset. The cut away fuselage, which gives a considerably improved rear view, prevents the fitting of a 72 gallon tank."

Vickers built 633 LF.IX and 89 HF.IX September to December 1944 and another 475 LF.IX and 100 HF.IX in 1945.

The range figures in Air 19/286 are similar to the proposals from the first half of 1944 reported in AVIA 20/2030 and AIR 20/3312, see messages 228 and 229 in the Spitfire Combat Radius (range) evolution, limitations? topic

Spitfire Combat Radius (range) evolution, limitations?

Both the F4U and F6F were almost as big and heavy as the P-47 and they did their best work low down, below 20,000 feet. The key was the R-2800 and it's tremendous horsepower.

ww2aircraft.net

Also in AIR 19/286 the Spitfire LF.IXE with Merlin 66, maximum weak mixture cruise speed was 328 mph at 20,000 feet, most economical cruise was 220 mph at 20,000 feet, this gives fuel load (85 gallons internal, rest external) / MEC range / MWM range
85 / 434 / 240
130 / 721 / 387
175 / 980 / 520
255 / 1,355 / 765.

The Spitfire XIV with 112 gallons internal range was 460 miles, a 62 gallon rear fuselage tank was predicted to increase this to 770 miles. Mark XIV range with 112 internal and 30 gallon external 610 miles, 112+45 = 680 miles, 112+90 = 850 miles, 112+170 = 1,130 miles. The Spitfire XXI had an extra 8 gallons internal and cruised about 8 mph faster than the XIV. The Mustang III with 150 gallons of fuel range 950 miles, with 221 gallons internal 1,450 miles, with 150 internal and 125 external 1,710 miles, with 221 internal and 125 external 2,210 miles, economic cruise of 253 mph at 20,000 feet.

The RAF standard was ranges of fighters are shown as ranges at maximum economic cruising power on the fuel available, after deducting fuel used in 15 minutes at maximum power at sea level. This allowance is for warming up and climbing to operational height. The Tempest came in at about a short ton heavier than the P-51D.

 

[Deleted member 68059]

As promised some pages from the British Air Intelligence files on the Me110. Reading these has significantly warmed me to the aircraft.

 

[Conslaw]

There were numerous bombing missions which flew under 26,000 feet. Of 372 bombing missions of the 303rd Bomb Group, the lowest bombing altitude:

11,000 to 13,900 feet:  11  ( 3.0%)
14,000 to 16,900 feet:  18  ( 4.8%)
17,000 to 19,900 feet:  31  ( 8.3%)
20,000 to 22,900 feet:  77  (20.7%)
23,000 to 25,900 feet: 178  (47.8%)
26,000 to 28,900 feet:  54  (14.5%)
29,000 and over:         3  ( 0.8%)

Those three missions with minimum bombing altitude over 29,000 must have been interesting.

 

[Stig1207]

Williamson Murray, Luftwaffe strength 28 June 1940 1,107 Bf109 to 357 Bf110, or about 3 to 1 Bf19 to Bf110

Wood and Dempster, 10 August 1940, Bf109 1,101 establishment, 934 strength, 805 serviceable, Bf110 301 / 289 / 224, or over 3 to 1 Bf109 to Bf110.

So Bergstrom reports the Bf110 force scored about 1 confirmed kill for each of its initial strength, the Bf109 about 0.8. Then when you factor in multi engine multi crew aircraft generate fewer sorties per aircraft than single engine single seaters, and the close escort tactics, Bergstrom is reporting the Bf110 was a much better fighter than the Bf109, longer ranged, scoring as high as maybe 50% more confirmed kills per sortie over the course of the Battle of Britain, if allowed to optimise its tactics.

The Battle of Britain Then and Now says Fighter Command had 1,026 total losses for the Battle, with 798 due to enemy action and 40 more unknown, of the enemy action losses 672 are attributed to enemy fighters or enemy aircraft. Bergstrom has 1,120 confirmed kills by Luftwaffe fighters, which means up to another 450 non RAF Fighter Command aircraft are confirmed shot down, which would be mostly from Bomber Command and Coastal Command. Bergstrom says over the Battle of Britain the Luftwaffe fighters shot down 3 Fighter Command to 2 other RAF command aircraft. Bomber Command lost 382 aircraft in the period to all causes, 103 by day, 279 by night, 187 of the losses came down on British territory. Using Boiten's Nachtjagd War Diaries and the Bomber Command Losses series 15 day and 23 night losses are due to Luftwaffe fighters, 14 more losses are to unknown causes.

That still leaves hundreds from Coastal Command to make up the numbers, total all causes losses on operations for all of 1940 were 310, few are logged as lost to fighters, see Coastal Command Losses by Ross McNeill.

The old Luftwaffe kill claims list I have for the Battle of Britain has ZG26 and ZG76 but is missing ZG2, the ZG units logging 231 claims, some of which were disallowed, the JG units 1,894, again including some that were disallowed. Bergstrom more than halves the Bf109 claims, but must have several hundred more claims by Bf110 that the old list I have is missing.

Williamson Murray, losses to end September 1940, Bf109 398 enemy, 79 ops, 41 non ops, Bf110 214 enemy, 9 ops, 12 non ops

The Battle of Britain Then and Now listing, 10 July to 31 October has the total all causes losses on operations as Spitfire 353, Hurricane 569, Bf109 600, Bf110 248.

Bergstrom reports, July to October, Spitfire 394, Hurricane 603, Bf109 534, Bf110 196

Luftwaffe Quartermaster reports as translated by the RAF, July to October Bf109 600, Bf110 235, plus 18 night fighters.

Williamson Murray, Luftwaffe, table IX says in the July to September period the Luftwaffe single engined fighter units lost 47% of their original strength, the twin engined units 66%. For May and June 1940 Murray reports the Luftwaffe single engined fighter units lost 19% of their original strength, the twin engined units 30%, for May to September, single engined fighter units lost 57% of their original strength, the twin engined units 97%,

Bergstrom's total of confirmed kills by Luftwaffe fighters, at 1,120, is hundreds more than can be confirmed by RAF records and post war investigations, his fighter losses for the RAF higher and Luftwaffe lower than the air force records.

The main reported Bf110 failing was poor acceleration, which would be a big problem on close escort sorties.

Andrew Arthy posted the following charts from Luftwaffe Quartermaster reports at some stage, perhaps on this forum?

So the 600 Bf 109's lost are to all causes on operations, 502 to enemy action and 98 without enemy action. Bergström's total losses to enemy action is actually higher for the 109's, by 32 aircraft.