Author Topic: 100/150 fuel useage (Read 1915 times)

MiloMorai · « **on:** June 11, 2005, 05:26:11 AM »

The average of British production of this grade of fuel was 56.3% of avgas production from Feb 44 to Mar 45 and only going under 50% for 3 months (Apr, May 44, Mar 45). Highest production was in Jan 45 with 77.1%.

A Lancaster carried 24 times (2154gal vs 88gal) the quantity of fuel than a Spitfire. Or to put it another way, one Lancaster would carry enough fuel for the requirement of 1.5 Spitfire squadrons, @ 16 a/c.

The Nov 44 150 production is the nearest to the average at 54.8% (6,030,500gal vs 4,966,500gal). This is enough fuel for 2300 Lancasters/Halifaxes.

Considering the number of bombers (Lancaster, Halifax) that would not use 100/150 fuel and the quantity of 100/130 fuel they carried, it would seem that fighter use of 100/150 grade fuel was extensive since why produce such quantity if it was not required and not used.

Discussion now open on how extensive the use of 100/150 fuel was.

Kev367th · « **Reply #1 on:** June 16, 2005, 08:18:58 PM »

May 1944 - 2 Spit L.F. IX squadrons converted to 150 grade/25lbs boost. Only know 2 (1 and 165 sqns) for definate as I have seen pics of logs. But could easily surmise a lot more did.

Nov 1944 - Whole of the 2nd TAF Spits (IXe, XIV, and XVIe) with Merlin 66, 266 or Griffon 65 given clearance to use 150 grade fuel. Merlins @ 25lb boost, Griffon @ 21lb boost.

Should be implemented on the Spit remodel.
Replace current Spit F IX (least made) with a Spit L.F. IX/XVI Merlin 66/266 with 150 grade/25lbs boost.

Listing both the IX and XVI, as the XVI was basically a IX with a Packard Merlin 266 (American built Merlin 66). So could be done as either.

Would you mind if I used your figures in something I am putting together?
Could you point me to where/how you found out?

Thanks

Scherf · « **Reply #2 on:** June 16, 2005, 09:07:12 PM »

Look up Neil Stirling somewhere. He is "the man" on this issue.

1K3 · « **Reply #3 on:** June 16, 2005, 10:33:40 PM »

Quote

Originally posted by Kev367th

Replace current Spit F IX (least made) with a Spit L.F. IX/XVI Merlin 66/266 with 150 grade/25lbs boost.

Then RAF will have a gap for 1942-43 fighter planeset.

currently RAF has '43-44 gap.

Kev367th · « **Reply #4 on:** June 16, 2005, 10:58:10 PM »

Nope the current Spit 5 is a late 1942 model

For 1943 I suggest a Spit VIII - Apart from one sqn, all Far East sqns used it. (1000+ built)

I actually suggested this lineup

1939 Spit Ia Merlin II to 12lbs boost as per 1939, not 6lb as in AH
1942 Spit Vc Merlin 50 (current)
1943 Spit L.F. VIIIe Merlin 66, clipped wings
1944 Spit L.F. IXe/XVIe Merlin66/266 150 fuel/25 boost
1944 Spit VIX Griffon 65 (current)

Guppy35 · « **Reply #5 on:** June 17, 2005, 12:22:52 AM »

Quote

Originally posted by Kev367th
Nope the current Spit 5 is a late 1942 model

For 1943 I suggest a Spit VIII - Apart from one sqn, all Far East sqns used it. (1000+ built)

I actually suggested this lineup

1939 Spit Ia Merlin II to 12lbs boost as per 1939, not 6lb as in AH
1942 Spit Vc Merlin 50 (current)
1943 Spit L.F. VIIIe Merlin 66, clipped wings
1944 Spit L.F. IXe/XVIe Merlin66/266 150 fuel/25 boost
1944 Spit VIX Griffon 65 (current)

Gotta go with regular wing tipped Spit VIII Kev. The RAAF and CBI birds were all regular wing tips. Most of the other VIIIs were as well. Some clipped VIIIs in the Med later on but not many.No E wing on a VIII either. just the universal wing with the 2 20mm and 4 303.

Clip the LFIX/XVI as many were in 44-45 for the low level work.

Dan/CorkyJr

Naudet · « **Reply #6 on:** June 17, 2005, 02:44:28 AM »

One question about the clipped wing spitfires.

I read that the shorter wing really improved rollrate but had an adverse effect on stall characteristics. With the clipped wing the spit became prone to snap stalls in tight turns - similar to the FW190 - and the stall speed was somewhat higher than with the non-clipped wing.

Anyone - Neil or MW - have any experience/comparison reports about that?

KurfÃ¼rst · « **Reply #7 on:** June 17, 2005, 06:25:47 AM »

Naudet, I think the clipped wing Spits deserve their own thread.

But basically, clipping the wings was of little use and the RAF decided against it.

KurfÃ¼rst · « **Reply #8 on:** June 17, 2005, 06:33:54 AM »

Quote

Originally posted by Kev367th
May 1944 - 2 Spit L.F. IX squadrons converted to 150 grade/25lbs boost. Only know 2 (1 and 165 sqns) for definate as I have seen pics of logs. But could easily surmise a lot more did.

2 Squadrons? That`s doesn`t seem to be much of force, rather than operational testing. To my knowladge, there were 50+ MkIX squadrons in Britain alone during DDay.

Does anyone have fuel delivery documents to specific RAF squadrons that would show how much widespread the use of that fuel and boost was in view of the entire fighter force?

Was it common, or just a lucky minority using it for V-1 busting?

Kev367th · « **Reply #9 on:** June 17, 2005, 07:09:40 AM »

The operational testing had already been carried out.
The only reason I mention 2 specific sqns is because I have seen pictures of the logs which mention the change.

The delay in the 2TAF getting full clearance was due to a small number of aircraft having backfires.
Once this was fixed (July 1944) it states "All engines capable of using this type of fuel will be modified"

All engines refers to Merlin 66/266 and Griffon 65 used bt Spit IXe/XVIe/XIV.

2TAF alone was cleared for 25 sqns of Mk IX, 5 Sqns Mk XVI, 5 Sqns Mk XIV to be modified.
RAF takes 20 aircraft per sqn as strength, whcih gives us 500 Mk IXs, 100 Mk XVI, 100 Mk XIV using 150/25 boost.
This doesnt include "Home Command".

KurfÃ¼rst · « **Reply #10 on:** June 17, 2005, 07:16:21 AM »

I have seen that document on the 2nd TAF, too, it mentions, iirc, 25+5 Sqns of IX/XVI, and 5 Sqn of XIV.

Anyone has a strenght report on the 2nd TAF in this period? I have seen such for it`s typhoon sqns, but they are very varying - sometimes 1-2 plane per squadron being operational (on avarage!), other times, 16-18...

Given the above, I think 3-400 fighters would be a good estimate. How many fighters the RAF had in 44/45?

MiloMorai · « **Reply #11 on:** June 17, 2005, 07:27:32 AM »

Tell me Barbarossa Isegrim why would the British produced 114,919,000 Imp gal of 150 grade fuel? This was 55.7% of avgas production from Feb 44.

The USAAF flew 570,097 fighter sorties in the ETO, but that ~115 million gallons was enough for 1,305,898 Spitfire sorties. You want us to believe it was only 'penny pocket' usage for V-1 busting?

Kev367th,

this is the document > POWE 33/1363. I can send it to you.

KurfÃ¼rst · « **Reply #12 on:** June 17, 2005, 07:46:13 AM »

Quote

Originally posted by MiloMorai
The USAAF flew 570,097 fighter sorties in the ETO, but that ~115 million gallons was enough for 1,305,898 Spitfire sorties.

According to you, and I doubt there`d be muc htruth in it : primarly because there weren`t as many Spitfire sorties during the whole war.

MiloMorai · « **Reply #13 on:** June 17, 2005, 07:54:19 AM »

Quote

Originally posted by Kurfürst
According to you, and I doubt there`d be much truth in it : primarly because there weren`t as many Spitfire sorties during the whole war.

I did not say that was how many sorties, only that it was enough for that many.

Kev367th · « **Reply #14 on:** June 17, 2005, 08:02:19 AM »

D-Day the RAF had approx 32 sqns of Spit IX including the 2TAF.

So remove the 25 sqns cleared for 150 grade fuel in Nov leaves 7 non Merlin 66/266 sqns.
That is a vast majority of Spit IXe's cleared for 150-grade/25lbs boost.
Plus the backfire document July 1944 that clearly states -
"All engines capable of using this type of fuel will be modified" , not some or a couple but ALL.

Would point to the theory that most were converted once full clearence was given, in 2TAF case Nov 1944.