The Great P-47 Range Debate on you tube now. (1 Viewer)

[Geoffrey Sinclair]

The fundamental limit is the amount of internal fuel left after combat less reserves and in 1943 the P-47D allocated 89 gallons combat and 36 gallons reserves, leaving a maximum of 190 gallons to come home on and that assumes external tanks can refill internal ones. To have the numbers in 1943 requires acceleration of the P-47 program, including personnel training, by 6 or more months.

The calculations say the P-47D clean will use 101 gallons of fuel and move 57 miles during Warm-up, Take-off, and Climb to 25,000 feet, rising to 125 gallons and 81 miles with 300 gallons of external fuel. Assuming a 100 gallon class external tank can refill the internal ones used for the warm up, take off and initial climb the external fuel is gone even before crossing the English coast, if the external tank cannot refill the internal ones then it will last closer to the European coast and there is noticeably less internal fuel to come home on. One of the 1943 calculations states a maximum of 235 gallons external which indicates no ability to refill the internal tanks.

From the net,
London Schweinfurt 463 miles
London Aachen 274 miles
London Dover 67 miles
Most US bases north and east of London.

The various combat radius calculations mentioned in message 143 result in only 1 combination giving the required radius at altitude, with 2 more falling short. And those combinations require the large wing tanks reported as causing handling difficulties.

First what if the specification for the XP-47B results in the 556 gallons of internal fuel in the P-47N meaning a 100 or so gallon under fuselage tank is more a bonus.

Next what if the specification for the XP-47B results in the 370 gallons of internal fuel in the P-47D-25, giving 255 gallons to come home on, the various calculations fall short of Schweinfurt (let alone Regensburg), unless there are wing racks, then they can carry 324 gallons of external fuel in 3x108 gallon tanks with apparently no handling issues and given the fuel used in climb and to enemy coast the wing tanks can usually be released over occupied western Europe, cutting overall drag.

As Bill Marshall is pointing out the reality is maximum 1943/early 1944 P-47D radius looks to be around 300 miles with 100 gallons external and 420 miles for 300 gallons, the later from a theory of around 500 miles. Thanks to all the penalties of formation flying and the range of pilot skills and aircraft states. Experience did refine things like combat allowances and cruise settings, but so did the Luftwaffe pulling further back from the coast enabling slower speeds and/or slower climbs early as did the liberation of France and Belgium by end September 1944. It will be good to see the actual 1944 figures.

Staying low enough to fully use the ferry tank the P-47 made it to Aachen.

In 1943 the 8th Air Force generally managed to keep its P-47 group strength at 75 aircraft, 3 groups from April, another from 12 August, the fifth on 9 September, the sixth on 14 September, the seventh on 15 October, the eighth on 13 December, the ninth on 20 December, meantime the first P-38 group on 15 October and the second on 28 December and a P-51 group from 5 December. Early October it was 18 bomb groups to 6 fighter, end October 20 to 8, end December 25 to 12.

Spitfire VIII with 126 gallons of fuel internal, 90 external, combat radius around 300 miles at 320 mph at 20,000 feet, again assuming the external can refill the internal tanks, retaining all that are built in Britain, allocating them to the 8th Air Force and assuming around half production is available for front line strength end May 1943 would add the equivalent of 1 to 1.5 groups of escorts and around 4 by end October.

Going to Schweinfurt in a combat worthy P-47D in 1943.

The RAF appreciates the Spitfire range limits in late 1942 and changes production so Spitfire V or IX with 85 gallons have the late war 2x18 gallons wing tanks, total 121 gallons. Kits are provided to upgrade earlier production. The RAF now has the numbers to escort the heavy bombers out to and back from around 250 miles. The P-47 have the 108 gallon external tank, hop from their bases to airfields near the coast, cutting the distance to around 400 miles, they are refuelled maybe even with engines running to further save fuel, take off and are treated as bombers for the first and last 250 miles, economic cruise, straight line. At 250 miles the final climb and acceleration. Landings are at forward bases, maybe then you can make it with your 4 groups in August and 6 in October covering the final 200 or so miles to Schweinfurt but it looks like they will still fall short in reality, compared with theory because of the internal fuel limits, even with relay tactics. Plus the number of Luftwaffe interceptors, particularly in October.

250 miles from the US bases gets you to around the northern German border, just short of the Ruhr, 375 miles gets you to more or less to the arc Hamburg/Hanover/Kassel/Frankfurt/Karlsruhe

The USAAF did not have the numbers, experience or equipment during 1943 to mount credible diversions, spoofs, radar jamming etc, compounded by the early B-17F having a combat radius of around 320 miles using 8th Air Force tactics. The Luftwaffe was quickly able to spot the heavy bomber formations and for deeper raids learnt to wait until the escorts turned back. Hence why each new increase in escort range tended to initially produce high returns. After 2 years of RAF attacks on France, Belgium and the Netherlands the Luftwaffe was well versed in spotting fighter sweeps and short range bomb raids.

Richard Davis figures. The target list ignores Target of Opportunity, night and YB-40 sorties, the total tonnage includes them, 1943 8th Air Force attacks on German targets, 120 entries on 49 raid days, 1 in January, 4 in February (2 recalled), 3 in March, 1 in April, 4 in May, 4 in June, 6 in July, 2 in August, 2 in September, 7 in October, 8 in November and 7 in December. The campaign was very end weighted, the operations November 1943 to February 1944 were an important foundation to the air battles in 1944, denying the Luftwaffe for the first time a quiet period to refit and refresh its fighter units.

8th Air Force Bombs dropped on Germany in 1943, short tons

Month	Bombs
Jan-43​	137.5​
Feb-43​	259.3​
Mar-43​	532​
Apr-43​	263​
May-43​	1286.5​
Jun-32​	1803.7​
Jul-43​	2050.9​
Aug-43​	1298.7​
Sep-43​	1091.5​
Oct-43​	4184.9​
Nov-43​	5383.5​
Dec-43​	8893.7​
Total	27185.2​

8th Air Force Targets attacked in Germany in 1943 with number of bombers credited with attacking, 25 June emission convoy of Wangerooge, 17 July mission Hannover and Hamburg.

Date	City	Atk
27-Jan-43	Emden	2
27-Jan-43	Wilhelmshaven	53
01-Feb-43	Hamm	0
04-Feb-43	Emden	39
14-Feb-43	Hamm	0
26-Feb-43	Wilhelmshaven	64
04-Mar-43	Hamm	16
18-Mar-43	Vegesack	97
22-Mar-43	Wilhelmshaven	84
17-Apr-43	Bremen/Borgward	106
14-May-43	Kiel/Krupp	126
15-May-43	Emden	59
19-May-43	Flensberg	55
19-May-43	Kiel/Krupp	103
21-May-43	Emden/Nordseewerke	45
21-May-43	Wilhelmshaven	77
21-May-43	Wilhelmshaven	1
11-Jun-43	Cuxhaven	30
11-Jun-43	Misc., Ge	17
11-Jun-43	Wilhelmshaven	168
11-Jun-43	Wilhelmshaven	1
13-Jun-43	Bremen/Deschimag	102
13-Jun-43	Kiel	16
13-Jun-43	Kiel/Deutsche	44
13-Jun-43	Nordholz	11
22-Jun-43	Huls	170
25-Jun-43	Juist Island	18
25-Jun-43	Misc., Ge	143
25-Jun-43	Wangerooge Island	2
17-Jul-43	Misc., Ge	29
17-Jul-43​	Misc., Ge	1
17-Jul-43	Rheine	4
25-Jul-43	Hamburg/Blohm & Voss	68
25-Jul-43	Heide	14
25-Jul-43	Kiel/Deutsche	67
25-Jul-43	Misc., Ge	50
25-Jul-43	Rerik/West	18
26-Jul-43	Bremerhaven	1
26-Jul-43	Hamburg/Howald	54
26-Jul-43	Hannover/Gummiwerke	42
26-Jul-43	Hannover/Nordhafen	50
26-Jul-43	Langerooge	16
28-Jul-43	Kassel/Bettenhausen/Fieseler	47
28-Jul-43	Oschersleben/AGO Flugzugwerke	28
29-Jul-43	Heligoland	32
29-Jul-43	Kiel/Deutsche/Krupp	48
29-Jul-43	Kiel/Kriegsmarine	42
29-Jul-43	Warnemunde/Heinkel	54
30-Jul-43	Kassel	3
30-Jul-43	Kassel/Bettenhausen/Fieseler	94
30-Jul-43	Kassel/Waldau/Fieseler	37
12-Aug-43	Bochum/Vereinigte Stahl	117
12-Aug-43	Bonn	106
17-Aug-43	Frankfurt-am-Main	1
17-Aug-43	Heilbronn	1
17-Aug-43	Regensburg/Ober-Traubling	126
17-Aug-43	Schweinfurt/Kugelfisher	54
17-Aug-43	Schweinfurt/VKF 1	78
17-Aug-43	Schweinfurt/VKF 2	51
06-Sep-43	Karlsruhe	17
06-Sep-43	Offenburg	51
06-Sep-43	Stuttgart	46
27-Sep-43	Emden	178
27-Sep-43	Esens	18
27-Sep-43	Hannover	4
02-Oct-43	Emden	339
04-Oct-43	Frankfurt-am-Main	37
04-Oct-43	Frankfurt-am-Main/Heddern	78
04-Oct-43	Saarlautern	67
04-Oct-43	Wiesbaden	16
08-Oct-43	Bremen	197
08-Oct-43	Bremen/Deutsche	44
08-Oct-43	Bremen/Weser	33
08-Oct-43	Oldenburg	18
08-Oct-43	Vegesack	43
09-Oct-43	Anklam	106
09-Oct-43	Danzig	23
09-Oct-43	Marienburg	96
10-Oct-43	Coesfeld	68
10-Oct-43	Dulmen	1
10-Oct-43	Munster	138
14-Oct-43	Schweinfurt/Kugelfisher	81
14-Oct-43	Schweinfurt/VKF 1	61
14-Oct-43	Schweinfurt/VKF 2	86
20-Oct-43	Duren	97
03-Nov-43	Wilhelmshaven	539
05-Nov-43	Coesfeld	1
05-Nov-43	Gelsenkirchen	232
05-Nov-43	Gelsenkirchen/Buer	49
05-Nov-43	Gelsenkirchen/Nordstern	47
05-Nov-43	Munster	106
07-Nov-43	Duren	38
07-Nov-43	Wesel	54
11-Nov-43	Munster	59
13-Nov-43	Bremen	117
13-Nov-43	Flensberg	6
13-Nov-43	Kiel	1
26-Nov-43	Bremen	422
26-Nov-43	Vegesack	2
29-Nov-43	Bremen	137
29-Nov-43	Emmerich	1
29-Nov-43	Oldenburg	1
30-Nov-43	Solingen	79
01-Dec-43	Siegburg	17
01-Dec-43	Solingen	261
11-Dec-43	Emden	523
13-Dec-43	Bremen	175
13-Dec-43	Hamburg	116
13-Dec-43	Kiel/Krupp	353
13-Dec-43	Neumunster	1
16-Dec-43	Bremen	528
16-Dec-43	Wessermunde	1
20-Dec-43	Bremen	465
20-Dec-43	Oldenburg	1
22-Dec-43	Cologne	1
22-Dec-43	Munster	197
22-Dec-43	Osnabruck	218
22-Dec-43	Rheine	1
30-Dec-43	Ludwigshafen/I. G. Farben	653
30-Dec-43	Saarbrucken	4

 

[drgondog]

I think I remember glancing somewhere in the case history that the AAC did attempt to pressurize this tank and it wasn't satisfactory. I want to say there was also the same tank contracted by McKenzie Muffler that probably could have been pressurized.

McKenzie steel tank went to UK in summer 1942 but did not follow P-38 migration to N.Africa for Bolero.

But don't take that as gospel truth. I've poured over the case history a lot last week and I might be hallucinating/remembering wrong detail.


I am currently working on something of an alternative history scenario that is basically amounts to "What sequence of events would have to happen for P-47 to be able to escort to Schweinfurt in 1943.?"

1. The largest obstacle is the lack of wing tanks and the decision to go with centerline tank in 1942.

I would say the single most important obstacle was Republic refusal to deliver on Kelsy instruction to mount 3x75-gal tanks on P-47 as summarized in his March 27, 1942 reply to Chief, Engineering at Wright Field. Had Republic complied with standard AN-B-7 bomb racks the P-47 would have been introduced in ETO with both the modified Keel with standard bomb/drop tank attachment as well as wing pylons. What would have changed is the design of the 205-gal 'bullfrog' tank as it was designed for existing four-point attach scheme.

"2. The next hang up is the pressurization of tanks. Gregs 200 gallon metal tank probably would have existed if McKenzie Muffler was selected as the sub contractor instead of Ohio Rubber Company The tank would then at least be able to be pressurized in August 1943 but doesn't solve the "everything else" wrong with the tank."

See above, the 150/165-gal steel tank already in place in UK.

3. Presumably if the wing tank solution is available in early 1943 then triple-relay system could be implemented with combination of triple 75 gallon tanks that were on hand and the 150 gallon Lockheed tanks leftover from P-38.

Yes, but for certain the 150/165-gal tank would also have been avaialable. The issue here would be the timng of re-supply of both the 75 and 150-gal steel tanks from US.

4. This is assuming that the vacuum slaving system is ready to go by then and I believe that it was or could be.

IMO Hough certainly would have focused earlier, given steel tank availability.

Even with those 4 assumptions we run into a bunch of other problems. Of which are the following.

1. Can the 2x150 gallon tank P-47 actually provide target escort to Schweinfurt? It can make it if they don't have to S-weave with the bombers but might be just short if it does not.

I believe Yes is the answer for 56th FG out of Halesworth but marginal for 4th and 78th FG 40 mi farther away. None could go to Regensburg, even up to D-Day standards..

2. If it cannot make it to Schweinfurt then does the roughly 1/3rd of the fighter strength at the time make a material difference if forced to perform a fighter sweep? Or does Luftwaffe GCI just route their fighter formations around the escorts? This was something they could do in 1944 and 45 but that system is probably less efficient in 1945? What do the numbers look like in August?

Only four VIII FC Fg's operational in mid August 1943. Sweep from 56th FG feasible to ambush from Aachen to Schewinfurt - but all engaged would have to return no father than Frankfurt area. Of the four, the 353rd went operational on August 12th and very green.

Gregs hypothetical 200 gallon tank doesn't make it if you apply 70% correction factor to his estimate which was the cited discrepancy in one of our previous documents. It reduces his estimated range to around 300 miles. This also assumes that 70% correction factor in FAREP is accurate.

Remember that the flight envelope for that tank was 200mph IAS, a very dangerous low speed over the continent. 310mi was the combat radius of Neal Kearby Wewak mission - a Fighter, not escort type, with 200-gal steel tank.

3. How many missions in 1943 did the 8th Airforce take that would have required the 2x150 tanks. They only had around 800 on hand so that is optimistically only 400 sorties.

Schweinfurt, 410-420mi from Halesworth. The Bordeaux mission (P-38/P-51) on Dec 31st and the Regenburg mission Aug 17 were 100mi too far.

IMO, the critical factor was not listening to AAF request/orders: re: more internal fuel (until P-47D-25) and the refusal to put standard racks on belly and wing on P-47B as directed in March 1942.

 

[Squish]

The fundamental limit is the amount of internal fuel left after combat less reserves and in 1943 the P-47D allocated 89 gallons combat and 36 gallons reserves, leaving a maximum of 190 gallons to come home on and that assumes external tanks can refill internal ones. To have the numbers in 1943 requires acceleration of the P-47 program, including personnel training, by 6 or more months.

The calculations say the P-47D clean will use 101 gallons of fuel and move 57 miles during Warm-up, Take-off, and Climb to 25,000 feet, rising to 125 gallons and 81 miles with 300 gallons of external fuel. Assuming a 100 gallon class external tank can refill the internal ones used for the warm up, take off and initial climb the external fuel is gone even before crossing the English coast, if the external tank cannot refill the internal ones then it will last closer to the European coast and there is noticeably less internal fuel to come home on. One of the 1943 calculations states a maximum of 235 gallons external which indicates no ability to refill the internal tanks.

From the net,
London Schweinfurt 463 miles
London Aachen 274 miles
London Dover 67 miles
Most US bases north and east of London.

The various combat radius calculations mentioned in message 143 result in only 1 combination giving the required radius at altitude, with 2 more falling short. And those combinations require the large wing tanks reported as causing handling difficulties.

First what if the specification for the XP-47B results in the 556 gallons of internal fuel in the P-47N meaning a 100 or so gallon under fuselage tank is more a bonus.

Next what if the specification for the XP-47B results in the 370 gallons of internal fuel in the P-47D-25, giving 255 gallons to come home on, the various calculations fall short of Schweinfurt (let alone Regensburg), unless there are wing racks, then they can carry 324 gallons of external fuel in 3x108 gallon tanks with apparently no handling issues and given the fuel used in climb and to enemy coast the wing tanks can usually be released over occupied western Europe, cutting overall drag.

As Bill Marshall is pointing out the reality is maximum 1943/early 1944 P-47D radius looks to be around 300 miles with 100 gallons external and 420 miles for 300 gallons, the later from a theory of around 500 miles. Thanks to all the penalties of formation flying and the range of pilot skills and aircraft states. Experience did refine things like combat allowances and cruise settings, but so did the Luftwaffe pulling further back from the coast enabling slower speeds and/or slower climbs early as did the liberation of France and Belgium by end September 1944. It will be good to see the actual 1944 figures.

Staying low enough to fully use the ferry tank the P-47 made it to Aachen.

In 1943 the 8th Air Force generally managed to keep its P-47 group strength at 75 aircraft, 3 groups from April, another from 12 August, the fifth on 9 September, the sixth on 14 September, the seventh on 15 October, the eighth on 13 December, the ninth on 20 December, meantime the first P-38 group on 15 October and the second on 28 December and a P-51 group from 5 December. Early October it was 18 bomb groups to 6 fighter, end October 20 to 8, end December 25 to 12.

Spitfire VIII with 126 gallons of fuel internal, 90 external, combat radius around 300 miles at 320 mph at 20,000 feet, again assuming the external can refill the internal tanks, retaining all that are built in Britain, allocating them to the 8th Air Force and assuming around half production is available for front line strength end May 1943 would add the equivalent of 1 to 1.5 groups of escorts and around 4 by end October.

Going to Schweinfurt in a combat worthy P-47D in 1943.

The RAF appreciates the Spitfire range limits in late 1942 and changes production so Spitfire V or IX with 85 gallons have the late war 2x18 gallons wing tanks, total 121 gallons. Kits are provided to upgrade earlier production. The RAF now has the numbers to escort the heavy bombers out to and back from around 250 miles. The P-47 have the 108 gallon external tank, hop from their bases to airfields near the coast, cutting the distance to around 400 miles, they are refuelled maybe even with engines running to further save fuel, take off and are treated as bombers for the first and last 250 miles, economic cruise, straight line. At 250 miles the final climb and acceleration. Landings are at forward bases, maybe then you can make it with your 4 groups in August and 6 in October covering the final 200 or so miles to Schweinfurt but it looks like they will still fall short in reality, compared with theory because of the internal fuel limits, even with relay tactics. Plus the number of Luftwaffe interceptors, particularly in October.

250 miles from the US bases gets you to around the northern German border, just short of the Ruhr, 375 miles gets you to more or less to the arc Hamburg/Hanover/Kassel/Frankfurt/Karlsruhe

The USAAF did not have the numbers, experience or equipment during 1943 to mount credible diversions, spoofs, radar jamming etc, compounded by the early B-17F having a combat radius of around 320 miles using 8th Air Force tactics. The Luftwaffe was quickly able to spot the heavy bomber formations and for deeper raids learnt to wait until the escorts turned back. Hence why each new increase in escort range tended to initially produce high returns. After 2 years of RAF attacks on France, Belgium and the Netherlands the Luftwaffe was well versed in spotting fighter sweeps and short range bomb raids.

Richard Davis figures. The target list ignores Target of Opportunity, night and YB-40 sorties, the total tonnage includes them, 1943 8th Air Force attacks on German targets, 120 entries on 49 raid days, 1 in January, 4 in February (2 recalled), 3 in March, 1 in April, 4 in May, 4 in June, 6 in July, 2 in August, 2 in September, 7 in October, 8 in November and 7 in December. The campaign was very end weighted, the operations November 1943 to February 1944 were an important foundation to the air battles in 1944, denying the Luftwaffe for the first time a quiet period to refit and refresh its fighter units.

8th Air Force Bombs dropped on Germany in 1943, short tons

Month	Bombs
Jan-43​	137.5​
Feb-43​	259.3​
Mar-43​	532​
Apr-43​	263​
May-43​	1286.5​
Jun-32​	1803.7​
Jul-43​	2050.9​
Aug-43​	1298.7​
Sep-43​	1091.5​
Oct-43​	4184.9​
Nov-43​	5383.5​
Dec-43​	8893.7​
Total	27185.2​

8th Air Force Targets attacked in Germany in 1943 with number of bombers credited with attacking, 25 June emission convoy of Wangerooge, 17 July mission Hannover and Hamburg.

Date	City	Atk
27-Jan-43	Emden	2
27-Jan-43	Wilhelmshaven	53
01-Feb-43	Hamm	0
04-Feb-43	Emden	39
14-Feb-43	Hamm	0
26-Feb-43	Wilhelmshaven	64
04-Mar-43	Hamm	16
18-Mar-43	Vegesack	97
22-Mar-43	Wilhelmshaven	84
17-Apr-43	Bremen/Borgward	106
14-May-43	Kiel/Krupp	126
15-May-43	Emden	59
19-May-43	Flensberg	55
19-May-43	Kiel/Krupp	103
21-May-43	Emden/Nordseewerke	45
21-May-43	Wilhelmshaven	77
21-May-43	Wilhelmshaven	1
11-Jun-43	Cuxhaven	30
11-Jun-43	Misc., Ge	17
11-Jun-43	Wilhelmshaven	168
11-Jun-43	Wilhelmshaven	1
13-Jun-43	Bremen/Deschimag	102
13-Jun-43	Kiel	16
13-Jun-43	Kiel/Deutsche	44
13-Jun-43	Nordholz	11
22-Jun-43	Huls	170
25-Jun-43	Juist Island	18
25-Jun-43	Misc., Ge	143
25-Jun-43	Wangerooge Island	2
17-Jul-43	Misc., Ge	29
17-Jul-43​	Misc., Ge	1
17-Jul-43	Rheine	4
25-Jul-43	Hamburg/Blohm & Voss	68
25-Jul-43	Heide	14
25-Jul-43	Kiel/Deutsche	67
25-Jul-43	Misc., Ge	50
25-Jul-43	Rerik/West	18
26-Jul-43	Bremerhaven	1
26-Jul-43	Hamburg/Howald	54
26-Jul-43	Hannover/Gummiwerke	42
26-Jul-43	Hannover/Nordhafen	50
26-Jul-43	Langerooge	16
28-Jul-43	Kassel/Bettenhausen/Fieseler	47
28-Jul-43	Oschersleben/AGO Flugzugwerke	28
29-Jul-43	Heligoland	32
29-Jul-43	Kiel/Deutsche/Krupp	48
29-Jul-43	Kiel/Kriegsmarine	42
29-Jul-43	Warnemunde/Heinkel	54
30-Jul-43	Kassel	3
30-Jul-43	Kassel/Bettenhausen/Fieseler	94
30-Jul-43	Kassel/Waldau/Fieseler	37
12-Aug-43	Bochum/Vereinigte Stahl	117
12-Aug-43	Bonn	106
17-Aug-43	Frankfurt-am-Main	1
17-Aug-43	Heilbronn	1
17-Aug-43	Regensburg/Ober-Traubling	126
17-Aug-43	Schweinfurt/Kugelfisher	54
17-Aug-43	Schweinfurt/VKF 1	78
17-Aug-43	Schweinfurt/VKF 2	51
06-Sep-43	Karlsruhe	17
06-Sep-43	Offenburg	51
06-Sep-43	Stuttgart	46
27-Sep-43	Emden	178
27-Sep-43	Esens	18
27-Sep-43	Hannover	4
02-Oct-43	Emden	339
04-Oct-43	Frankfurt-am-Main	37
04-Oct-43	Frankfurt-am-Main/Heddern	78
04-Oct-43	Saarlautern	67
04-Oct-43	Wiesbaden	16
08-Oct-43	Bremen	197
08-Oct-43	Bremen/Deutsche	44
08-Oct-43	Bremen/Weser	33
08-Oct-43	Oldenburg	18
08-Oct-43	Vegesack	43
09-Oct-43	Anklam	106
09-Oct-43	Danzig	23
09-Oct-43	Marienburg	96
10-Oct-43	Coesfeld	68
10-Oct-43	Dulmen	1
10-Oct-43	Munster	138
14-Oct-43	Schweinfurt/Kugelfisher	81
14-Oct-43	Schweinfurt/VKF 1	61
14-Oct-43	Schweinfurt/VKF 2	86
20-Oct-43	Duren	97
03-Nov-43	Wilhelmshaven	539
05-Nov-43	Coesfeld	1
05-Nov-43	Gelsenkirchen	232
05-Nov-43	Gelsenkirchen/Buer	49
05-Nov-43	Gelsenkirchen/Nordstern	47
05-Nov-43	Munster	106
07-Nov-43	Duren	38
07-Nov-43	Wesel	54
11-Nov-43	Munster	59
13-Nov-43	Bremen	117
13-Nov-43	Flensberg	6
13-Nov-43	Kiel	1
26-Nov-43	Bremen	422
26-Nov-43	Vegesack	2
29-Nov-43	Bremen	137
29-Nov-43	Emmerich	1
29-Nov-43	Oldenburg	1
30-Nov-43	Solingen	79
01-Dec-43	Siegburg	17
01-Dec-43	Solingen	261
11-Dec-43	Emden	523
13-Dec-43	Bremen	175
13-Dec-43	Hamburg	116
13-Dec-43	Kiel/Krupp	353
13-Dec-43	Neumunster	1
16-Dec-43	Bremen	528
16-Dec-43	Wessermunde	1
20-Dec-43	Bremen	465
20-Dec-43	Oldenburg	1
22-Dec-43	Cologne	1
22-Dec-43	Munster	197
22-Dec-43	Osnabruck	218
22-Dec-43	Rheine	1
30-Dec-43	Ludwigshafen/I. G. Farben	653
30-Dec-43	Saarbrucken	4

How do the range calculations get impacted by the practice of manual leaning or whatever the fuel saving measures that were suggested by Lindbergh later in the war?

 

[bauple58]

My biggest regret was the frequent disconnect when Greg was speaking as I was effing around with my iphone - and also not having access to my notes. I mssed several key statements that just weren't challenged.

On that topic, did Greg EVER cite facts regarding Arnold's acts of 'deceipt and treachery' to prevent LR tanks from ETO? Did he do so with Kenney when Kenney went to Ford in June 43, or when Eaker went to Bowater-Loyd in March 1943? Did he prevent Lockheed and NAA and Curtiss and Bell from subcontracting steel tanks after the famous quoted telex which paraphrased, said 'don't deliver aircraft with auxiliary tanks at gov't expense, but do what you want with your own nickel"?

Did Arnold block dispatch of four P-38FGs to 8th AF in spring 1942, and again in July 1943 when he re-routed 20th and 55th FG to 8th AF (BEFORE Schweinfurt-Regensburg).

Greg got away with misstating the particulars of the Kearby Wewak MOH mission and hung his P-47 Range/200 gal Brisbane tank by claiming the mission was from Port Moresby. It was in fact from Lae (200mi from Port Moresby), where his flight landed and refueled - then flew 300mifor the 20min fight (not for one hour), returned to Lae to refuel again. That 200gal belly tank range was ~ same as the single 108gal tank used by 56th FG 309mi over Bremen October 13th (2 days after Kearby mission).

John Bruning's Ace Race, page 240-250'ish

Nor did he quote the Kenney Report correctly by stating that P-39 tanks were sent. There was no item identified on pg 264- only that it took too much effort to modify. That would have been another reason to point at lack of common (B-7/B-10) bomb rack that already existed on the other fighters (P-38, P-39, P-40) in 1942.

Nor was he held to answer why Arnold picked Chennault, Bereton, Kenney to run 14th, 10th&9th, and 5th AF - no bomber mafioso in that group, nor was Doolittle for that matter.

The attached spreadsheet highlights longest combat engagements flown for 56FG with each of the tank combinations. Missions identified with 8th AF Victory Credits Board June 1945 but Kent Miller's Pilots and Units of 8th AF Fighter command pretty well matches the VC Board data. Brisbane tank - Post in thread 'P-47 drop tanks' P-47 drop tanks

 

[bauple58]

My biggest regret was the frequent disconnect when Greg was speaking as I was effing around with my iphone - and also not having access to my notes. I mssed several key statements that just weren't challenged.

On that topic, did Greg EVER cite facts regarding Arnold's acts of 'deceipt and treachery' to prevent LR tanks from ETO? Did he do so with Kenney when Kenney went to Ford in June 43, or when Eaker went to Bowater-Loyd in March 1943? Did he prevent Lockheed and NAA and Curtiss and Bell from subcontracting steel tanks after the famous quoted telex which paraphrased, said 'don't deliver aircraft with auxiliary tanks at gov't expense, but do what you want with your own nickel"?

Did Arnold block dispatch of four P-38FGs to 8th AF in spring 1942, and again in July 1943 when he re-routed 20th and 55th FG to 8th AF (BEFORE Schweinfurt-Regensburg).

Greg got away with misstating the particulars of the Kearby Wewak MOH mission and hung his P-47 Range/200 gal Brisbane tank by claiming the mission was from Port Moresby. It was in fact from Lae (200mi from Port Moresby), where his flight landed and refueled - then flew 300mifor the 20min fight (not for one hour), returned to Lae to refuel again. That 200gal belly tank range was ~ same as the single 108gal tank used by 56th FG 309mi over Bremen October 13th (2 days after Kearby mission).

John Bruning's Ace Race, page 240-250'ish

Nor did he quote the Kenney Report correctly by stating that P-39 tanks were sent. There was no item identified on pg 264- only that it took too much effort to modify. That would have been another reason to point at lack of common (B-7/B-10) bomb rack that already existed on the other fighters (P-38, P-39, P-40) in 1942.

Nor was he held to answer why Arnold picked Chennault, Bereton, Kenney to run 14th, 10th&9th, and 5th AF - no bomber mafioso in that group, nor was Doolittle for that matter.

The attached spreadsheet highlights longest combat engagements flown for 56FG with each of the tank combinations. Missions identified with 8th AF Victory Credits Board June 1945 but Kent Miller's Pilots and Units of 8th AF Fighter command pretty well matches the VC Board data.

You may find that the term Brisbane tank was never used in the 1940s, being something created by barefoot historians late last century :

P-47 drop tanks



Post in thread 'P-47 drop tanks' P-47 drop tanks

 

[Shortround6]

How do the range calculations get impacted by the practice of manual leaning or whatever the fuel saving measures that were suggested by Lindbergh later in the war?

The big problem, as has been said by others, is that operational radius is governed by the amount of fuel inside the airplane when the external tanks are dropped. Few, if any, WW II aircraft could refill internal tanks from the drop tanks.
Or at least to any real extent. The Aircraft fuel systems provided more fuel to the carb/fuel injector than needed but only around 1-2 gallons extra per hour? This overflow fuel was directed to ONE internal tank instead of returned to the tank is was being drawn from.
Unless you add extra pumping capacity and extra fuel lines/valves and venting, filling the internal tanks was not happening.

Does anybody have the specifics of what Lindbergh was suggesting for different aircraft?
For the P-38s it didn't take a lot.
1. stop flying like the army was telling it's pilots to fly (front line officers).
2. Fly like both Allison and Lockheed were telling the pilots to do.

Lindbergh helped the F4U pilots in the Pacific with R-2800 engines......................except
1. F4Us didn't use turbos.
2. F4Us didn't cruise at 25,000ft
3. F4Us didn't Cruise at 205-210IAS at 25,000ft.
3A, F4Us in the Pacific could cruise at lower speeds over water with no AA guns and with very few enemy fighter fields of to one side or the other.
Cruising slow in areas where enemy fighters could attack was a good way to get dead or captured.

The Army, at least at first, didn't want the pilots using boost from the turbo-charger for cruising. Trying to get the turbo to go from around 10,000rpm (?) to 18,000rpm took a while, Getting the 22,000rpm on the later model turbos took a bit longer.

As far as just sticking a pair of 150-165 gallon tanks on any/all P-47s in England in Aug 1943 goes...........
The Paddle blade props don't start showing up until Dec 1943. Water injection started showing up Nov. 1943.
You actually have to get the P-47s off the existing runways with large fuel loads. An extra 1000lbs could require an extra 300-400ft of runway, Not all fields had the same length runways although the bulldozers were busy, as were the concrete and pavement trucks.
Maybe I am making mountains out of mole hills but a lot of things had to come together for the Jan 1944 and later bombing campaign aside from just more/bigger drop tanks.
More/larger tanks on the P-47 could have added some range to escort missions in late 1943.

Charts for the P-47 show that the extra 65 gallons of internal fuel was worth around 100 miles for radius without external tanks (125miles to 225 miles) while that same 65 gallons of fuel was worth 175 miles when carrying a pair of 150 gal tanks. (425 miles vs 600 miles).
it doesn't matter how much fuel you can carry in, what matters is how much fuel you have to get out once you have dropped the tanks and fought for 15-20 minutes.

 

[tomo pauk]

Few, if any, WW II aircraft could refill internal tanks from the drop tanks.
Or at least to any real extent.

German fighters (109s, 190s) were pumping the fuel from the drop tanks to the main (internal) fuel tanks as a rule, and the engine was fed from the main tanks.
So did the Fulmar (I'm not sure about the Firefly), F6F-5 (but not the -3), the F4U from IIRC -4 onwards, and all F8Fs.

 

[wuzak]

Schweinfurt, 410-420mi from Halesworth.

Direct, or along a planned route?

 

[Squish]

The big problem, as has been said by others, is that operational radius is governed by the amount of fuel inside the airplane when the external tanks are dropped. Few, if any, WW II aircraft could refill internal tanks from the drop tanks.
Or at least to any real extent. The Aircraft fuel systems provided more fuel to the carb/fuel injector than needed but only around 1-2 gallons extra per hour? This overflow fuel was directed to ONE internal tank instead of returned to the tank is was being drawn from.
Unless you add extra pumping capacity and extra fuel lines/valves and venting, filling the internal tanks was not happening.

Does anybody have the specifics of what Lindbergh was suggesting for different aircraft?
For the P-38s it didn't take a lot.
1. stop flying like the army was telling it's pilots to fly (front line officers).
2. Fly like both Allison and Lockheed were telling the pilots to do.

Lindbergh helped the F4U pilots in the Pacific with R-2800 engines......................except
1. F4Us didn't use turbos.
2. F4Us didn't cruise at 25,000ft
3. F4Us didn't Cruise at 205-210IAS at 25,000ft.
3A, F4Us in the Pacific could cruise at lower speeds over water with no AA guns and with very few enemy fighter fields of to one side or the other.
Cruising slow in areas where enemy fighters could attack was a good way to get dead or captured.

The Army, at least at first, didn't want the pilots using boost from the turbo-charger for cruising. Trying to get the turbo to go from around 10,000rpm (?) to 18,000rpm took a while, Getting the 22,000rpm on the later model turbos took a bit longer.

As far as just sticking a pair of 150-165 gallon tanks on any/all P-47s in England in Aug 1943 goes...........
The Paddle blade props don't start showing up until Dec 1943. Water injection started showing up Nov. 1943.
You actually have to get the P-47s off the existing runways with large fuel loads. An extra 1000lbs could require an extra 300-400ft of runway, Not all fields had the same length runways although the bulldozers were busy, as were the concrete and pavement trucks.
Maybe I am making mountains out of mole hills but a lot of things had to come together for the Jan 1944 and later bombing campaign aside from just more/bigger drop tanks.
More/larger tanks on the P-47 could have added some range to escort missions in late 1943.

Charts for the P-47 show that the extra 65 gallons of internal fuel was worth around 100 miles for radius without external tanks (125miles to 225 miles) while that same 65 gallons of fuel was worth 175 miles when carrying a pair of 150 gal tanks. (425 miles vs 600 miles).
it doesn't matter how much fuel you can carry in, what matters is how much fuel you have to get out once you have dropped the tanks and fought for 15-20 minutes.

The reason that I ask is because I think at least being able to ballpark estimate the effects of "Lindbergh Leaning" or whatever moniker we want to call it is something that would probably put the final nail in the coffin for the whole P-47 business. I am not ignoring the internal fuel but rather just trying to get an understanding of what, if any, extra range could be squeezed out of the existing fuel if "better" practices could have been followed.

I am sure that drgondog probably has a decent idea or would be able to find a source that would be able to provide one. My personal opinion is that I would not be surprised if Cass Hough/8th Airforce was already flying the plane to nearly the maximum possible range and that any potential change from messing with fuel mixture vs turbo-rpm would have been negligible.

 

[drgondog]

How do the range calculations get impacted by the practice of manual leaning or whatever the fuel saving measures that were suggested by Lindbergh later in the war?

They are improved, and continuously improved with flight testing.

You may find that the term Brisbane tank was never used in the 1940s, being something created by barefoot historians late last century :

P-47 drop tanks

I do know that, but easier to refer to it that way in this forum because everyone knows where it was used.

Direct, or along a planned route?

Direct, straight line -- the most 'optimistic' compared to actual, and frequent dog legs around flak concentrations.

 

[elbmc1969]

"REFERENCE 6TH WRAPPER INDORSEMENT, APRIL 29, 1939, SUBJECT: "FUEL CAPACITY OF P-36A AIRPLANE, GHQ FILE 452.11, THE CHIEF OF THE AIR CORPS DIRECTS THAT NO TACTICAL AIRPLANE WILL BE EQUIPPED WITH DROPPABLE AUXILIARY FUEL TANKS. THERE ARE NO OBJECTIONS TO THE CURTISS COMPANY MAKING SUCH AN INSTALLATION ON THEIR P-36 TYPE AIRPLANE WITHOUT EXPENSE TO THE GOVERNMENT."

The key word here is "equipped." It does not say, "no tactical airplane will be capable of carrying droppable auxiliary fuel tanks." Planes are come plumbed from drop tanks? Fine.

But we're not buying any drop tanks for our airplanes!

Maybe this is a subtle difference, but I think that it's an important one.

 

[elbmc1969]

1) You say there were concerns about the tanks' safety. I know that Messerschmitt had serious concerns about their papier maché drop tanks. Apparently there were examples of the tank leaking fumes and the aircraft exploding in mid air. The lack of range was clearly a major problem for the 109 over London in 1940 and while that was a good example of where drop tanks might have worked. Was this part of the USAAC's concern? Or was it a release problem, aerodynamic or otherwise?

According to the USAF history of drop tanks in WWII, the concern was that escort fighters carrying drop tanks would not consume all of the fuel in the external tanks before crossing into enemy airspace. While dropping the tank prior to combat was desirable, it seemed obvious that there was a good chance that the escorts would get bounced, particularly since the drop tanks added drag and, if the drop tanks did what they were supposed to, the aircraft would be at near maximum internal fuel. That meant that the interceptors were likely to be both fast than the escorts and attacking from higher altitude.

Fire was the specific hazard. The fear was that a single machine gun bullet passing through a metal drop tank with some fuel still in it would inevitably cause a spark. If the drop tank still had fuel in it, it would be filled with flammable gas. Even an empty tank was almost certain to be flammable. A fire or fuel-air explosion in the drop tank could spread to the body of the aircraft, or travel up the fuel pipe from the drop tank into the aircraft's main internal fuel system.

Metal tanks were too expensive to simply drop on every mission as soon as they were empty. The development of tanks that filled with inert gas as they emptied was one solution to this problem. Paper tanks were another branch of the solution--you still needed to fill them with inert gas, but you could afford to eject them as soon as they were empty.

 

[J.D.]

The key word here is "equipped." It does not say, "no tactical airplane will be capable of carrying droppable auxiliary fuel tanks." Planes are come plumbed from drop tanks? Fine.

But we're not buying any drop tanks for our airplanes!

Maybe this is a subtle difference, but I think that it's an important one.

I agree. Subtlety is important. And the comment about Curtiss tends to support your position.

 

[drgondog]

The key word here is "equipped." It does not say, "no tactical airplane will be capable of carrying droppable auxiliary fuel tanks." Planes are come plumbed from drop tanks? Fine.

But we're not buying any drop tanks for our airplanes!

Maybe this is a subtle difference, but I think that it's an important one.

AAC/AAF made no attempt to discourage Curtiss and Bell from designing and delivering both the racks and tanks in mid 1940 and it encouraged Lockheed beginning August 1940 to deliver fuel feed and bomb tracks for the proposed 75-gal tank already being contracted by Curtiss and Bell for testing.

 

[PAT303]

Spitfire VIII with 126 gallons of fuel internal, 90 external, combat radius around 300 miles at 320 mph at 20,000 feet, again assuming the external can refill the internal tanks, retaining all that are built in Britain, allocating them to the 8th Air Force and assuming around half production is available for front line strength end May 1943 would add the equivalent of 1 to 1.5 groups of escorts and around 4 by end October.

It's funny how I have said this very thing numerous times on here yet every time I got shut down, Mk VIII/IX's could have easily escorted raids right to Germany from the start of '43 but apparently increasing the Spits fuel capacity was simply too hard, fitting cannons, bombs, numerous different engines, making them float planes, carrier planes, glider tugs photo recon etc etc etc was doable but fitting extra fuel tanks, nope can't be done.

 

[drgondog]

It's funny how I have said this very thing numerous times on here yet every time I got shut down, Mk VIII/IX's could have easily escorted raids right to Germany from the start of '43 but apparently increasing the Spits fuel capacity was simply too hard, fitting cannons, bombs, numerous different engines, making them float planes, carrier planes, glider tugs photo recon etc etc etc was doable but fitting extra fuel tanks, nope can't be done.

The 'problem' was that the configuration you envisioned was not one RAF deemed important. There was no daylight strategic role that required removing lesser fuel capacity Spitfires from production deliverables. Every Spitfire modified and tasked to provide escort for 8th AF would be handicapped vs the Fw 190 with its higher fuel fraction lowering climb performance.

 

[PAT303]

The 'problem' was that the configuration you envisioned was not one RAF deemed important. There was no daylight strategic role that required removing lesser fuel capacity Spitfires from production deliverables. Every Spitfire modified and tasked to provide escort for 8th AF would be handicapped vs the Fw 190 with its higher fuel fraction lowering climb performance.

And so would have every other fighter in the same situation, a fighter loaded with fuel is going to struggle against one that's not, what could have happened is P47's could have flown escort sweeps ahead of the escort Spits until the their rear fuel burned down enough allowing combat maneuvers, the Merlin 45 was cleared in February for 18psi boost settings so the abundance of MkV's would have been useful also. The bombers coming back from Schweinfurt would have paid money out of their own pockets for escort fighters 300 miles from home.

 

[tomo pauk]

The 'problem' was that the configuration you envisioned was not one RAF deemed important. There was no daylight strategic role that required removing lesser fuel capacity Spitfires from production deliverables.

That is the kicker - no official requirement means no hardware.

Every Spitfire modified and tasked to provide escort for 8th AF would be handicapped vs the Fw 190 with its higher fuel fraction lowering climb performance.

Bill - how much of fuel should the Spitfire IX or VIII had in the internal tanks (or, how heavy should they be) so the Fw 190 of 1943 can out-climb them at 25000 ft and above? Assumes normal weaponry on the 190 (ie. no underslung cannons or rockets), as well as 'normal' altitude engines on the Spits (ie. no low-altitude LF versions).
How much should the Spitfire XIV (Griffon with a 2-stage S/C) weight, in order for the 'normal' Fw 190 A7 or A8 to out-climb it at 25000 ft and above?

 

[drgondog]

That is the kicker - no official requirement means no hardware.


Bill - how much of fuel should the Spitfire IX or VIII had in the internal tanks (or, how heavy should they be) so the Fw 190 of 1943 can out-climb them at 25000 ft and above? Assumes normal weaponry on the 190 (ie. no underslung cannons or rockets), as well as 'normal' altitude engines on the Spits (ie. no low-altitude LF versions).
How much should the Spitfire XIV (Griffon with a 2-stage S/C) weight, in order for the 'normal' Fw 190 A7 or A8 to out-climb it at 25000 ft and above?

The FW 190A-7/A-8 should never outclimb the Spit VIIIIX at any altitude, but the margin is smaller with 90-100 gal remaining at beginning of combat after releasing tanks. Ditto XIV.

 

[tomo pauk]

The FW 190A-7/A-8 should never outclimb the Spit VIIIIX at any altitude, but the margin is smaller with 90-100 gal remaining at beginning of combat after releasing tanks. Ditto XIV.

Thank you, I was thinking on the similar lines. I think that the Mk. XIV will handily beat any non-jet German fighter of 1944, even with double the fuel fraction (tricky to do due to the CoG, though).

My train of thought is something like this, for our Spitfires with more fuel - I prefer a 40-50 imp gal tank behind the pilot, or something similar, and the Mk.VIII over the IX:

Allies can probably deploy as many of them, as target escort, in mid to late 1943, as the Germans can deploy of the Fw 190s. Neither aircraft has a major advantage that can reliably & definitely negate the enemy's advantage of position, altitude, speed and/or the pilot's skill (higher we go, Spitfire is better of the two, especially with the 70 series Merlins). Allies can also deploy the P-47s to do the roles of inbound and return escort, with a sprinkling of Typhoons to 'visit' the airfields, range permitting. Also the Spitfire Vs to plug the gaps, but closer to UK. 8th AF also deploys the heavies.
LW defenders have though choices to make: do they attack the initial escorts, or the target escort, or the 'retreating' escort, or the bombers? Or the Typhoons? They don't have nearly enough to attack all of them, and if they split the forces, they will fare badly in either task. The rocket-toting Bf 110s and Fw 190s are in severe problems.

IOW, Germans might have the parity in aircraft performance when we look at 1 vs. 1, however the numerical disadvantage is their big problem.