Battle over Germany, January, 1944

[davparlr]

P-51B, P-47 PreD-25, F4U-1, P-38J, Escort Ability vs. Me-109G and Fw-190A-8

This is a topic that should activate all the white knights out there.

I wanted to try to come grasp how these four aircraft would perform in the escort role over Germany against their German opponent. The F4U was thrown in because it was brought up as an aircraft that should have been built instead of the P-47 (and I think the P-51, too). First I wanted to define the requirements of an escort fighter for supporting daylight bombing of Berlin by B-17s and B-24s. This is what I determined was needed.
1. Range to fly to Berlin and back
2. Endurance to allow a meaningful combat time under enemy attack.
3. Equal-to or better capability of engaging enemy aircraft in combat at or above 20,000 ft.

Methodology

The methodology I used to compare these planes were, 1) determine total internal and external fuel available each aircraft, 2) calculate fuel required to transit to target (approx. 600 miles) at 25,000 ft, 3) calculate fuel required to return to base (I used ingress fuel since I am lazy and probably didn't have this data. Still should be okay for comparisons), 4) calculate fuel available for combat, 5) calculate combat time at Normal Rated Power (NRP), 6) compare performance at 20,000, 25,000, and 30,000 ft. Since the data available was not all compatible between aircraft (it never is), some alchemy was required to generate fuel consumption at 25,000 ft. It all seems to pass the smell test.

Assumptions.

1) Flight profile goes directly to Germany, optimum cruise, engage defenders, fly directly home. Weaving over slower bombers is not calculated but obviously would reduce time in combat. Comparisons are still valid.
2) Combat is engaged over target area and external fuel tanks jettisoned at commencement of combat. Again, if engaged inbound to target, combat time would be affected, but comparisons are still valid. Combat time would also be affected if a pilot hangs onto his tanks (which I don't think would be wise).
3) Normal Rated Power for combat is used for comparison purposes (another one of my simplifying decisions). Mil and max power will affect the higher HP aircraft to a greater extent (for example, a P-51 at max will be using less fuel than a P-47 because of the HP difference).
4) External fuel is a variable for most aircraft. In most cases, external fuel was enough to make it to the target area. The only exception was the F4U, which had to use some internal fuel to make the target.

References

1) Flight Operations Instructions Chart, P-51D and K,
2) Tactical Planning Characteristics Performance Chart, P-47
3) What appears to be a P-38 Pilot Handbook showing fuel consumption,
4) America's Hundred-Thousand
5) Other sources

Information Key

Internal fuel – Useable Fuel stored internally in the aircraft
External fuel – Fuel stored in jettisonable tanks
Transit Fuel – Fuel required to fly from home base to target area not including takeoff and climb
Return to base – Fuel required to return to home base
Fuel available at combat start – Fuel remaining after jettison of external fuel
Fuel available for combat – fuel remaining after jettison minus return to base
Combat time – Time to consume fuel available for combat at normal rated power

P-38J
Internal Fuel, 410 gal
External Fuel, 600 gal
Transit Fuel, 600 miles, 277 gal
Return to base, 600 miles, 277 gal
Fuel available at combat start, 410 gal
Fuel available for combat, 123 gal
Combat time at NRP, 35 min.

P-47D Pre -25
Internal Fuel 305 gal
External Fuel 410 gal
Transit Fuel, 600 miles, 261 gal
Return to Base, 600 miles, 261 gal
Fuel available at combat start, 305 gal.
Fuel available for combat 44 gal
Combat time at NRP, 16 min.

F4U-1
Internal Fuel, 351 gal
External Fuel, 175 gal
Transit Fuel, 600 miles, 186 gal
Return to Base, 600 miles, 186 gal
Fuel available at combat start, 340 gal (Note: internal fuel was required to be used for ingress after drop tank was empty.)
Fuel available for combat, 154 gal.
Combat time at NRP, 1 hour, 6 min.

P-51B
Internal Fuel 269 gal
External Fuel 216 gal
Transit Fuel, 600 miles 108 gal
Return to Base, 600 miles 108 gal
Fuel available at combat start 229 gal. Note: 85 gal fuselage tank used down to 65 gal for combat stability.
Fuel available for combat 121 gal
Combat time at NRP, 1 hr 14 min.

Performance at 20k ft. (B-24 Altitude)

P-38J
Airspeed, 410 mph
Climb, 3000 ft/min
Ceiling, 44,000 ft.

P-47D Pre -25
Airspeed, 402 mph
Climb, 1565 ft/min
Ceiling, 42,000 ft.

F4U-1
Airspeed, 430 mph
Climb, 2800 ft/min
Ceiling, 36,900 ft.

P-51B
Airspeed, 424 mph
Climb, 2915 ft/min
Ceiling, 42,000

Luftwaffe Opposition

Bf-109G
Airspeed, 399 mph
Climb, 3094 ft/min
Ceiling, 39,000

Fw-190A-8
Airspeed, 405 mph
Climb, 2400 ft/min
Ceiling 35,000 ft.

Performance at 25k ft. (B-17 Altitude)

P-38J
Airspeed, 415 mph
Climb, 2600 ft/min
Ceiling, 44,000 ft.


P-47D Pre -25
Airspeed, 435 mph
Climb, 2300 ft/min
Ceiling, 42,000 ft.

F4U-1
Airspeed, 424 mph
Climb, 1650 ft/min
Ceiling, 36,900 ft.

P-51B
Airspeed, 427 mph
Climb, 2600 ft/min
Ceiling, 42,000 ft.


Luftwaffe Opposition

Bf-109G
Airspeed, 420 mph
Climb, 2200 ft/min
Ceiling, 39,000 ft.

Fw-190A-8
Airspeed, 392 mph
Climb, 2,200
Ceiling, 35,000 ft.


Performance at 30k ft. (Top Cover)

P-38J
Airspeed, 415 mph
Climb, 1900 ft/min
Ceiling, 44,000 ft.

P-47D-20
Airspeed, 430 mph
Climb, 1300 ft/min
Ceiling, 42,000

F4U-1
Airspeed, 390 mph
Climb, 1,000 ft/min
Ceiling, 36,900 ft/min

P-51B
Airspeed, 441 mph
Climb, 2250 ft/min
Ceiling, 42,000 ft.

Luftwaffe Opposition

Bf-109G
Airspeed, 400 mph
Climb, 1625 ft/min
Ceiling, 39,000 ft.

Fw-190 A-8
Airspeed, 386 mph
Climb, 1080 ft/sec
Ceiling, 35,000 ft.

Observations:

P-38J
Very good range with average time in combat.
Competitive performance with opposition. Generally superior climb rate.
Good high altitude performance, excellent ceiling.
P-38 would probably be an effective escort with capable pilots

P-47D-20
Limited range, poor time in combat
Performance limited at 20k, much better as altitude increases
Very good high altitude performance.
P-47 effectiveness limited by range. Later P-47 versions solved this problem, especially the P-47N, with larger internal fuel capacity.

F4U-1
Excellent range, excellent time in combat
Capable performance at lower altitudes, suffers at high altitude, low ceiling.
F4U would suffer in escort duty due to lack of high altitude performance. The aircraft would have needed the -18W engine to adequately perform at the higher altitudes, this engine was not available until mid to late '44. Turbocharging was probably not an option. The F4U-4, available in May, '44, alleviates the high altitude performance problem, but reduced internal fuel would hamper escort ability.

P-51B
Excellent range, excellent time in combat
Comparable performance to opposition at 20k, outperforms Bf-109 and easily outperforms Fw-190 at 25k. Easily outperforms both at 30k.
The P-51B was most likely the most efficient propeller aircraft in WWII. Its speed/hp at SL is .246 mph/hp. Comparison to other aircraft, P-51D is .23, Fw-190D-9 is .217, Ta-152H is .18, F4U-1 is .162, and the P-47B is .15 (note that the F4U-1 is slightly more efficient than the P-47, which is reflected in the range numbers even though they have roughly the same engine). The efficiency of the P-51, combined with a moderate internal fuel load, and very good high altitude performance is the key to its supremacy in the escort fighter role.

Bf-109G
The Bf-109 has some good climb characteristics but suffers in airspeed. In general, it is somewhat competitive up to 25k. It is outperformed by the AF escort fighters above 25k.

Fw-190A-8
Except for the P-47 at 20k ft. and the F4U, the Fw-190 has significant performance shortcomings to the escort fighters at these altitudes.

At the altitudes where the bombers flew, except maybe the B-24, the Luftwaffe fighters had performance shortcomings, especially with the P-51. January to June, '44 was a critical time for Germany, being pressured by the Russians on the East and D-Day being prepared on the West and with ever increasing bomber formations over the homeland. The Germans were not able to adequately contend the airspace above 20k ft. until the advent of the Bf-109K and the Fw-190D-9 in late '44.

So, gird your loins and do battle with what I have presented and point out errors, which is always possible, in my logic and/or data.

 

[drgondog]

P-51B, P-47 PreD-25, F4U-1, P-38J, Escort Ability vs. Me-109G and Fw-190A-8

This is a topic that should activate all the white knights out there.

I wanted to try to come grasp how these four aircraft would perform in the escort role over Germany against their German opponent. The F4U was thrown in because it was brought up as an aircraft that should have been built instead of the P-47 (and I think the P-51, too). First I wanted to define the requirements of an escort fighter for supporting daylight bombing of Berlin by B-17s and B-24s. This is what I determined was needed.




Depends on exact location in UK bu 600 miles is good average

1. Range to fly to Berlin and back P-51B and P-51D (for Vincenzo)

2. Endurance to allow a meaningful combat time under enemy attack.

Planning Factors - Time and distance and cruise settings. For 'essing' time - whatever time it takes B-17s at their 150 IAS (~190mph in/~215mph TAS out) to get from R/V to target and back to B/E.. then multiply that by the cruise settings for minimum fuel consumption at that altitude. The Reach Altitude to RV is calculated at best cruise speed. The Break Escort to Let Down is at best cruise unless you have plenty to burn.


Planned endurance was Warm up and TO ~ 10-15 minutes, Asemble/Climb to cruise ~15-20 minutes, Cruise time to RV (different speed), Cruise time during escort at low cruise, "essing",Combat time at high throttle setting ~20 minutes, Cruise time return to Break Escort point, Cruise optimal to base, 20-30 minutes planned reserve at Base area..

3. Equal-to or better capability of engaging enemy aircraft in combat at or above 20,000 ft.

.

I'll try to pitch in as I have more time.

To help you back out some numbers here are some of the targets and times from Steeple Morden involving combat. Here are a few samples from 'his' logbook

Politz - battle near Rugen north of Berlin - no escort on return as they were relieved NNe of Berlin. June 20 1944 ...2 Me 109s destroyed 1 probable in turning combat - 5.15 hours

July 28 - Leipzig and back to B/E.. R/V near Mulhausen and combat near Mulhausen on way back1 Me 109 destroyed in diving combat.. 6.15 hours

June 21 - Ruhland. No combat. 7.15 hours

July 31 - Munich. No combat. 6.25 hours

Sep 11 - Miburg. 2 Me 109s destroyed- 1 damaged - near Marburg on way to target in a diving and a turning combat.

Sept 18 - Piryatin Russia after dropping supplies over Warsaw. Optimum cruise to R/V near Stettin Poland, then SW over target, break into a flight of Me 109s but no chase - low on fuel. 7.55 hours

I would have to really dig but I can get some R/V points on the above missions to help your cruise to R/V and R/V to Target times to help you out on fuel consumtion for those two specific Different Cruis settings.

 

[Vincenzo]

i've many doubt that actually that p47 d pre -25 can escort bomber over berlin

 

[drgondog]

i've many doubt that actually that p47 d pre -25 can escort bomber over berlin

I believe you are dead on.

As near as I can recall, the first time the 56th went 'deep' to Berlin was February 1945 with the new (buggy) P-47M. I do not believe they ever made it with any D but I have been wrong before.. That was one of the criteria to force all the remaining P-47 groups in the 8th AF over to 51s and give the Jugs away to 9th AF.

 

[ponsford]

davparlr: Two points that might warrant further scrutiny are a). Was the 190 A-8 operational in January 1944 and b). 420 mph in level flight for a standard 109 day fighter in January 1944 seems questionable.

 

[Njaco]

Any Jugs in the 15th AF and would that be a shorter distance to Berlin?

 

[drgondog]

Any Jugs in the 15th AF and would that be a shorter distance to Berlin?

Depends on date - the 12th/15th had a lot of Jugs in the Mrc 1944 timeframe including the 332nd (tuskeegee) at that time - no, they never went to Berlin to my knowledge...but I am not as well versed on the 15th AF

austrai, even Munich was a pretty deep penetration for them until near the end when Italy had been taken.

 

[Njaco]

It was just a thought. I'm not well versed on any Allied AF ops but was surmising that distance to Germany from Italy might have been shorter.

 

[Erich]

Ponsford is correct no A8's till end of March 44

 

[buzzard]

There was a turbocharged Corsair...the F4U-3. It was developed for high altitude work but problems with the turbos (and probably a lack of real incentive) led to it being dropped.

The FW-190 was tested against both the F4U-1 and the Hellcat. The FW 190 could outclimb them both, but the two navy fighters were more manouverable, and the Corsair was generally slightly faster, depending on altitude. I can't remember the model of the '190, but I do remember that it was a fighter version. That's about all I remember, but I got the report around here somewhere...

JL

 

[kool kitty89]

The F4U-1 would still have high alt performance equal or better than the Fw 190A-8 and previous. (crit alt ~21,000 ft at WEP compared to ~18,000 ft for the 190) Also note the F4U-1D had increased engine power and external load capacity.

The max external fuel load for a corsair would be with 2x 152 gal and 1x 178 gal tank, giving 482 US gal external in addition to the 352 gal internal. And the wing tanks were only removed on the F4U-4 because the extra range was not necessary for USN operations, so there's no reason a USAAF version would not have kept them.

Also note the P-51 could carry up to 300 US gal externally (2x 150 gal).

And your figures for the P-47 are inconsistant, no single model in the same configuration had climb rate increase with altitude (except below 10,000 ft in certain configurations) some of those figures are for the tootpic prop and some for the paddle, at 20,000 ft the P-47D-22 with Hamilton Standard prop should be climbing at ~2,700 ft/min, and ~2,450 ft/min at 25,000 ft.


some refrences

http://www.wwiiaircraftperformance.org/p-47/p-47-tactical-chart.jpg
http://www.wwiiaircraftperformance.org/p-38/p-38-tactical-chart.jpg
http://www.wwiiaircraftperformance.org/mustang/p-51-tactical-chart.jpg

P-47 Performance Tests
P-38 Performance Trials
P-51 Mustang Performance

 

[davparlr]

i've many doubt that actually that p47 d pre -25 can escort bomber over berlin

I think my calculations of combat time shows why, 16 min of NRP probably nothing at Mil or Max thus no combat capability.

 

[kool kitty89]

Yeah the extra 65 gal internal made a big difference. (increase combat time by 2.5x)
(but also note that on the lighter P-47D-22 and earlier models fuel economy is a bit better with max clean range of 835 mi for the D-22 compared to 800 mi for the D-23)

And also note (for the a/c with more fuel external, which is all in this case) that they can loiter over the combat area with drop tanks (or drop only some of the tanks, except fot the P-51 which has none on the centerline) and significantly increase loiter time, particularly in the cases of the P-47, F4U (with 3 drop tanks), and the P-38 with 2x 300 gal tanks. (though actually never used in the ETO)

Of course once you drop tanks (ie engage in combat) there's you're limiting factor.

 

[davparlr]

The F4U-1 would still have high alt performance equal or better than the Fw 190A-8 and previous. (crit alt ~21,000 ft at WEP compared to ~18,000 ft for the 190) Also note the F4U-1D had increased engine power and external load capacity.

However, the F4U-1D had lost its internal wing tanks affecting combat time. I am not sure high altitude performance is improved significantly. Also, the -1D did not begin production until April '44.

The max external fuel load for a corsair would be with 2x 152 gal and 1x 178 gal tank, giving 482 US gal external in addition to the 352 gal internal.

I do not think this capability was available on the -1, but rather the -1D.

And the wing tanks were only removed on the F4U-4 because the extra range was not necessary for USN operations, so there's no reason a USAAF version would not have kept them.

True, But the F4U-4 did not come available until Dec, '44.

And your figures for the P-47 are inconsistant, no single model in the same configuration had climb rate increase with altitude (except below 10,000 ft in certain configurations) some of those figures are for the tootpic prop and some for the paddle, at 20,000 ft the P-47D-22 with Hamilton Standard prop should be climbing at ~2,700 ft/min, and ~2,450 ft/min at 25,000 ft.

My data went bonkers somewhere. Couldn't be operator error.

 

[kool kitty89]

Also the performance values of the P-47 (of the same models) varied with later modifications and changed in boost restrictions with higher octane fuel. (the P-47D eventually topping out at 2,600 hp with 70" Hg manifold pressure, and 100/150 grade fuel, crit alt for this was just under 24,000 ft)

Of course other additions (pylons, and the increased fuel) decreased performance and each different prop (several different paddle props used on the D model) had advantages and disadvantages and different optimum areas of performance, the Hamilton Standard prop seems to have the best all-around performance though, according to figured on the above site.


And on the F4U-1D, I forgot the wing tanks had been deleted there, but as with the F4U-4, they would have stayed if used in this capacity. (probably with self sealing added)

And I think you're right that not until the -1D did it carry the other 2 drop tanks. And the greater engine power of this model didn't extend to high alt either iirc, (same supercharger iirc) so it wouldn't help there.

And the crit alt for WEP was ~20,000 ft, not 21,000 ft. (still about a 2,000 ft advantage over the 190)

 

[Kurfürst]

The Germans were not able to adequately contend the airspace above 20k ft. until the advent of the Bf-109K and the Fw-190D-9 in late '44.

That`s why they pressed the DB 605AS powered G-6/ASinto action in April 1944 (and then the G-14/AS in July which had MW boost as standard) , which they were toying with since late 1943, to serve as an interim solution for high altitude fighter until the perfection of the DB 605D/109K.

G-6/AS (w. MW50, but not all aircraft had it, though as far as high altitude performance goes, the presence of MW is unimportant). The G-14/AS performance should be exactly the same.

Kurfrst - Daimler-Benz A.G. - Horizontalgeschwindigkeiten mit MW 50 Leistung Me 109 GJ+FX.

G-6 performance: Kurfrst - Bf 109G-6 / DB 605 A

(420 mph at altitude seems a tad bit too much).

As far as I understand, in January 1944 there were very few - if any - P-47Ds with paddle blade props, and the ones without these topped out at 660 km/h at altitude, and very modest climb rates.

As Erich pointed out, no A-8s yet. A-7s were around at the start of 1944, but in very small numbers only (17); A-6s were the most numerous at 241; A-5s numbered 79 while the combined A-3/A-4s to 76; JG-5 in the North had still five A-2s.
(quick sorting of my strenght graphs, so some small errors may be present. Values represent operational units deployed anywhere on the map)

On the 109 front, G-5s and G-6s were totally dominant, out of 1166 operational Bf 109Gs 1031 being G-5/G-6 on 31 December 1943.

Very nice approach overall though!

 

[kool kitty89]

The toothpick prop offered slightly better high speed performance, at the expence of low speed performance and climb rate.

(top speed at 31,000 ft with 57" Hg, for D-22 or earlier was ~437 mph, without wing pylons which would cut ~10-15 mph iirc, although increased engine ratings again improved it this, with increased fuel consumption of course)

However at 25,000 ft speed was closer to 420-425 mph, and 409-417 at 20,000 ft.

 

[davparlr]

davparlr: Two points that might warrant further scrutiny are a). Was the 190 A-8 operational in January 1944

Yeah, I screwed that up. I didn't have detailed data on the A-6 so I went with the A-8, which I did have data, and thought they were similar enough. I should have expained that better.

and b). 420 mph in level flight for a standard 109 day fighter in January 1944 seems questionable.

I went back and reviewed my data and the best I came up with was about 417 mph, but I am not sure of this source, either.

 

[buzzard]

The report was based on the '44 Patuxent Naval Air Test Center "Report of Comparative Combat Evaluation of the Focke-Wulf 190A-4", in the 2005 Flight Journal 'German Fighters' issue. The comparison was between the Fw190A-4, F4U-1D, and the F6F-3.

Given that there is little material difference, performance-wise, between the A-4 and A-6, or between the F4U-1 and -1D, the conclusions reached in the report can be considered relevant to the matter at hand.

One note: The tested '190 lacked armament, and since no mention is made of any handling or CG-related problems, this probably enhanced the performance of the test plane, at least in comparison to the heavily-armed 'bomber-destroyer' variants.

I'm a lousy typist, so I'm giving a summmary, rather than quotes.

RoC: Best climb speed of the 190: 165 kts
----------------------------F4U: 135 kts
The 190 could break off an engagement at will by climbing.

Max speed: F4U was 25kts faster at 200ft; above 15,000 ft: Almost identical

Horizontal Acceleration: Near identical at all altitudes (from 160 kts and up)

RoR: Equal at high speeds. The 190 exhibited roll reversal at low speeds and in turns.

Manouverability: F4U was far superior in tight turns at any speed. At low speeds the 190 tended to exhibit aileron reversal and stall without warning, esp in left turns.
The F4U could also easily evade a rear attack by going into a tight loop.

Dive speed: Vmax is near-identical at all altitudes. No mention as to which accelerated faster.

Conclusion: The 190 did best by taking advantage of it's superior climb speed to make high-speed, one pass attacks with its superior armament.
The Corsair could evade attacks with its superior manouverability, and was the better dogfighter.

As the Corsair is as fast, and is more manouverable than the P-47, it stands to reason that it would also be a match for the '109 in combat below 30,000 ft.

The Corsair and Mustang, working together, would be more than a match for the Luftwaffe fighters, IMHO.

JL

 

[drgondog]

As far as I understand, in January 1944 there were very few - if any - P-47Ds with paddle blade props, and the ones without these topped out at 660 km/h at altitude, and very modest climb rates.

QUOTE]

Kurfurst - You are right.. the 56th FG started receiving Paddle Blade kits in January, 1944. I know that neither the 4th FG and 355th FG received them before the conversion to Mustangs in late Feb, 1944.

I want to say that post P-47D-10s' left the factory with the new prop also in December/January 1944.