The P-38J and L in the European theater.

[eagledad]

Gentlemen,

From the Mighty Eighth War Manual pages 220-221:

From page 221
The 8th AF used 6 sizes of drop tanks, some sizes produced with paper or steel.

P-47 with 1 75 gallon steel tank (actually held 84 gallons) had a radius of 280 miles.
P-47 with 1 108 gallon steel or paper tank (108 gallons) had a radius of 325 miles.
P-47 with 1 150 gallon steel tank (165 gallons) had a radius of 375 miles.
P-47 with 2 150 gallon steel tanks (2x165 gallons) had a radius of 550 miles.
P-47 with 1 200 gallon paper tank (205 gallons) had a radius of 275 miles. *
P-47 with 1 200 gallon steel tank (215 gallons) had a radius of 480 miles.
*This tank had a poor aerodynamic shape, would not take pressurization, and would leak if fuel were left in the tank for a few hours. It also would bounce along under the fuselage once released. This was the first drop tank tried by the 8th in the spring/summer of 1943.

P-51 with 2 75 gallon steel tanks (2x84 gallons) had a radius of 650 miles.
P-51 with 2 108 gallon paper tanks (2x108 gallons) had a radius of 750 miles.
P-51 with 2 110 gallon steel tanks (2x110 gallons) had a radius of 750 miles.

P-38 with 2 165 gallon steel tanks (2x165 gallons) had a radius of 600 miles.

Other notes:
In March 1944, all 75 gallon drop tanks held by P-47 units were transferred to P-51 units because of a shortage.
With the arrival of the 150 gallon tank in February 1944, it soon became the favored tank used by P-47 units. With the tank on the centerline, the wing shackles were available for other ordinance. Two 150 gallon tanks were carried (one under each wing) but the load made handling difficult.

During the time the P-38 was used by the 8th Air Force used the 150 gallon drop tank. No other special tanks were made. This tank was not pressurized and had to be released at 20,000 feet

The book does not state how the radius was/is computed, nor does it mention the total internal fuel each model carried.
FYI
Eagledad

 

[Navalwarrior]

'Wet wing' usualy means that part(s) of the wing was/were sealed, in order to carry fuel internally in the wing itself.
The 1st P-47s with wing racks probably came to the UK in August 1943 by overflying Atlantic in stages. I don't know whether such P-47s (ie. with wing racks) were used inn the ETO in more than token numbers before 1944.

Resp:
Roger on the 'wing racks' def. I know the wing racks plumb for fuel (P-47D-15 were first w 'wet pylons') didn't arrive until 1944. I believe at least one was on hand @ March 1944. Just not sure when they were first flown as escort.

 

[eagledad]

Navalwarrior,

A P-47D-15-RE, serial 42-75635 was shot down by FLAK on March 6, 1944. The Pilot, Major F Nelander was POW. The P-47 was from the 362nd FG
Just confirming what you wrote.

 

[Greyman]

Range and radius are not the same thing. Ranges usually do not include a combat allowance for one thing. I also doubt very highly that a Spitfire in May of 1943 was operating at a 175 mile radius without some sort of drop tank as the early Spitfires were operating at about a 120 mile radius when "clean".

I think I got my numbers right ...

Spitfire IX (Merlin 66) has 85 gallons.

Standard allowance for take-off and climb to 20,000 feet is 22.5 gallons
Five minutes of combat is 11.75 gallons

So we have 50.75 gallons to play with ...
At most economical speed we get a range of 352.41 miles
At maximum weak mix we get a range of 194.88 miles

So yeah, for that 175 mile combat radius it looks like we're gunna need a drop tank.

EDIT: unless it's acceptable to do the entire mission at 220 mph (most econ speed)

 

[Shortround6]

I think I got my numbers right ...

Spitfire IX (Merlin 66) has 85 gallons.

Standard allowance for take-off and climb to 20,000 feet is 22.5 gallons
Five minutes of combat is 11.75 gallons

So we have 50.75 gallons to play with ...
At most economical speed we get a range of 352.41 miles
At maximum weak mix we get a range of 194.88 miles

So yeah, for that 175 mile combat radius it looks like we're gunna need a drop tank.

EDIT: unless it's acceptable to do the entire mission at 220 mph (most econ speed)

Thanks, finding much detail on ranges for British fighters is a challenge. My only quibble is that the US used 5 minutes at WEP and 15 minutes at military power for the combat allowance so longer than 5 minutes could really cut into the Spitfires radius.

 

[Greyman]

I get 145.2 mile radius for the Spitfire IX (Merlin 66) with:

• take-off and climb to 20,000
• 15 minutes of maximum weak mix
• 5 minutes of combat power
• remainder at maximum economical

 

[Kevin J]

I think I got my numbers right ...

Spitfire IX (Merlin 66) has 85 gallons.

Standard allowance for take-off and climb to 20,000 feet is 22.5 gallons
Five minutes of combat is 11.75 gallons

So we have 50.75 gallons to play with ...
At most economical speed we get a range of 352.41 miles
At maximum weak mix we get a range of 194.88 miles

So yeah, for that 175 mile combat radius it looks like we're gunna need a drop tank.

EDIT: unless it's acceptable to do the entire mission at 220 mph (most econ speed)

I think you'll find that the only safe drop tank they could use for missions over Europe was the 30 gallon slipper tank, which you could retain in combat, IIRC radius of action was about 125 miles. There was a 45 gallon slipper tank that could be used safely for patrol work. There were also 90 and 170 gallon slipper tanks for ferrying, the later with armament reduced to 2 m/c IIRC. Both these tanks restricted the Spitfires to level flight only, no combat manoeuvres. So if you tried the 90 gal on a patrol mission, even the Me 110 would make mincemeat of you. A 60 gal Kittyhawk drop tank slung underneath a Seafire III gave you a combat radius of about 180 miles IIRC.

 

[Mike Williams]

I think you'll find that the only safe drop tank they could use for missions over Europe was the 30 gallon slipper tank, which you could retain in combat, IIRC radius of action was about 125 miles. There was a 45 gallon slipper tank that could be used safely for patrol work. There were also 90 and 170 gallon slipper tanks for ferrying, the later with armament reduced to 2 m/c IIRC. Both these tanks restricted the Spitfires to level flight only, no combat manoeuvres. So if you tried the 90 gal on a patrol mission, even the Me 110 would make mincemeat of you. A 60 gal Kittyhawk drop tank slung underneath a Seafire III gave you a combat radius of about 180 miles IIRC.

Spitfires used 90 gallon tanks on operations:

http://www.wwiiaircraftperformance.org/150grade/1-squadron-oprep-27aug44.jpg

http://www.wwiiaircraftperformance.org/111-kennedy-10sept43.jpg

http://www.wwiiaircraftperformance.org/610-ORB-1sept44.jpg

http://www.wwiiaircraftperformance.org/130_Oprep-12Sept44.jpg

http://www.wwiiaircraftperformance.org/41-OpRep-17Sept44.jpg

45 gallon tanks too:

http://www.wwiiaircraftperformance.org/150grade/165_oprep_16sept44.jpg

 

[Kevin J]

Spitfires used 90 gallon tanks on operations:

http://www.wwiiaircraftperformance.org/150grade/1-squadron-oprep-27aug44.jpg

http://www.wwiiaircraftperformance.org/111-kennedy-10sept43.jpg

http://www.wwiiaircraftperformance.org/610-ORB-1sept44.jpg

http://www.wwiiaircraftperformance.org/130_Oprep-12Sept44.jpg

http://www.wwiiaircraftperformance.org/41-OpRep-17Sept44.jpg

45 gallon tanks too:

http://www.wwiiaircraftperformance.org/150grade/165_oprep_16sept44.jpg

With one exception all these uses occurred in 1944 by which time the Luftwaffe was a spent force. The 1943 operation occurred at Salerno where the only Luftwaffe opposition was from Fw 190A jabos. Try that two years earlier and you're mincemeat for Me 110s.

 

[Shortround6]

Why can you carry 200 gallons under a P-47 and not be mincemeat for Bf 110s and yet the Spitfire with a 108 Us gallon (90 imp) is?
BTW 2 years before Salerno and you have Spitfire Vs.
Test in 1942 of a fully tropicalised Spitfire VB with 90 gallon tank shows a change in climb to 20,000ft to 10 minutes form 8 minutes when clean.
I believe the 30 gallon tank was self sealing, I don't know if any of the 45 gallon tanks were.

 

[Kevin J]

Why can you carry 200 gallons under a P-47 and not be mincemeat for Bf 110s and yet the Spitfire with a 108 Us gallon (90 imp) is?
BTW 2 years before Salerno and you have Spitfire Vs.
Test in 1942 of a fully tropicalised Spitfire VB with 90 gallon tank shows a change in climb to 20,000ft to 10 minutes form 8 minutes when clean.
I believe the 30 gallon tank was self sealing, I don't know if any of the 45 gallon tanks were.[/QUOTE
IIRC, Thunderbolts with belly tanks had a hard time. The 1941 Spitfire Vb was outclassed by both the Fw 190A and the Bf 109F-4. In 1941, the 90 gal slipper tank was for ferry only, when used for patrol, even the Me 110 could destroy it.

 

[Shortround6]

The whole idea of drop tanks was that you dropped them when you engaged in combat. Not carried them with you during the fight.

This was the whole idea of limiting the operational radius to the distance you could fly (at a reasonable exit speed, higher than most economical cruise) after dropping the tank and fighting at full throttle (or near it) for 10-20 minutes and allowing 20-30 minutes to find the home field or alternate and land.
Some of the later Spitfires did carry the 30 gal tank (or perhaps the 45 gal) in combat but then they had a lot more power (and used more fuel in combat).

 

[Kevin J]

The whole idea of drop tanks was that you dropped them when you engaged in combat. Not carried them with you during the fight.

This was the whole idea of limiting the operational radius to the distance you could fly (at a reasonable exit speed, higher than most economical cruise) after dropping the tank and fighting at full throttle (or near it) for 10-20 minutes and allowing 20-30 minutes to find the home field or alternate and land.
Some of the later Spitfires did carry the 30 gal tank (or perhaps the 45 gal) in combat but then they had a lot more power (and used more fuel in combat).

The 30 gal slipper could be retained in combat, the 45 gal dropped, which worked okay if the attachment hooks worked properly.

 

[Shortround6]

More than one US aircraft found it couldn't jettison it's drop tanks when desired.
at any rate here is a Data sheet for the Spit MK IX HF
http://www.spitfireperformance.com/spitfire-hfix-ads.jpg

Now when figuring ranges or radius please note that this sheet may be making no allowance for a reserve for landing. Figure 10-11 gallons for flying 20 minutes after getting over dry land to find either home base or alternate airfield and to land (possibly with several other aircraft in landing pattern ahead of you).

Operational planning also has to consider (add in a fudge factor) for the worst performing plane of the squadron/group.

 

[Mike Williams]

At times Spitfires fought, for various reasons, even with 90 gallon drop tank still attached; for example:

http://www.wwiiaircraftperformance.org/126-Rae-14aug44

 

[Navalwarrior]

The 30 gal slipper could be retained in combat, the 45 gal dropped, which worked okay if the attachment hooks worked properly.

Resp:
So are you stating that the 30 gallon tank was designed to be retained during air-to-air combat (assuming it is empty) in lieu of dropping them?

 

[Kevin J]

Resp:
So are you stating that the 30 gallon tank was designed to be retained during air-to-air combat (assuming it is empty) in lieu of dropping them?

 

[Kevin J]

No I read it somewhere on the internet. Yes, it could be dropped, but when you get bounced, do you have the time. The 45 gal had to be dropped. Anything above that and operating restrictions applied to the Spitfire flying it.

 

[fubar57]

I'm guessing by that statement that P-51/-47 aircraft always had the drop-tanks released before they were "bounced"

 

[Shortround6]

Yep, Us Americans had better eyesight and never got bounced.