Inaccurate performance data for BOB fighters in COD comparing to RL data

[Glider]

Originally Posted by Crumpp

It is not my theory. I don't know. It comes from what is considered the bible on the Spitfire's development, Morgan and Shacklady.

http://www.amazon.co.uk/Spitfire-His.../dp/0946219486

I just know nothing in this thread is convincing otherwise to make their conclusion invalid.

If you have a copy, look it up. If you don't and are interested in the Spitfire, get one.

Can I ask where in the book it says this as I cannot find it.

[Al Schlageter]

Originally Posted by Glider

Can I ask where in the book it says this as I cannot find it.

Pg 55 under the heading 100 OCTANE FUEL

This is the 1st edition.

[Crumpp]

Would be interesting to see those OOBs. There are some circulating in the internet, would be nice to compare them with other sources.

The source is the RAF's official History of the Battle of Britain by TCG James. I will scan them and post them when I get the chance.

my understanding is that the authors didn't make any conclusion

No they just state the facts as they know them. That is one of things that makes their book so good and so far, everything in it has been correct. Their research into the technical development of the Spitfire is profound.

I remember when people loved to post the Mach .98 dives of the recon Spitfire that lost a propeller available on that website "Spitfire Performance" as representative of the diving ability of the aircraft. Anybody with some knowledge of aerodynamics who reads Morgan and Shacklady can immediately spot the issue with that. Not only does the A&AEE officially retract those measurements but it is very easy to spot the fact the A&AEE had their static ports in the wrong location to get any kind of accurate speed measurement from their rake in the original report.

Not their fault, we just did not know as much about transonic flight and the difficulty in obtaining accurate airspeed measurements.

I agree the 800,000 ton strategic reserve requirement be built up before any squadrons convert probably comes from a pre-war estimate.

If it is correct, then there is absolutely no chance a single operational squadron flew with the fuel during the Battle of Britain. England simply did not have enough 100 Octane fuel on hand to come close to that reserve requirement.

Again, that is just speculation on my part. Morgan and Shacklady just listed the two facts we know but they were not writing a book on the history of the Oil Committee and strategic reserves.

1. An 800,000 ton Strategic Reserve was required to be on hand before a single aircraft flew operationally.

2. 16 Squadrons converted in September 1940.

They were doing the technical development of the Spitfire. The 16 squadrons is a very important part of that technical development and inline with the subject they were research. One can look at the 87 Octane consumption on the documents in this thread and easily tell that it was not until after September that 100 Octane became the predominate fuel used by the RAF.

[Al Schlageter]

Originally Posted by Crumpp

If it is correct, then there is absolutely no chance a single operational squadron flew with the fuel during the Battle of Britain. England simply did not have enough 100 Octane fuel on hand to come close to that reserve requirement.

They were doing the technical development of the Spitfire. The 16 squadrons is a very important part of that technical development and inline with the subject they were research. One can look at the 87 Octane consumption on the documents in this thread and easily tell that it was not until after September that 100 Octane became the predominate fuel used by the RAF.

So tell me Eugene why is there so many fighter squadrons using 12lb boost which can only be done when using 100 fuel?

This is just what I have even before the BoB started:

By Month

No. 32 Squadron pre BoB H
No. 92 (East India) Squadron pre BoB S
No. 111 Squadron pre BoB H
No. 151 Squadron Feb 1940 H
No. 602 (City of Glasgow) Squadron pre BoB S
No. 609 (West Riding) Squadron pre BoB S

No. 1 (Cawnpore) Squadron May 1940 H
No. 3 Squadron May 1940 H
No. 17 Squadron May 1940 H
No. 19 Squadron May 1940 S
No. 54 Squadron May 1940 S
No. 74 Squadron May 1940 S
No. 56 (Punjab) Squadron May 1940 H
No. 73 Squadron May 1940 H
No. 79 (Madras Presidency) Squadron May 1940 H
No. 85 Squadron May 1940 H
No. 87 (United Provinces) Squadron May 1940 H
No. 229 Squadron May 1940 H

No. 43 (China-British) Squadron June 1940 H
No. 41 Squadron June 1940 S
No. 610 (County of Chester) Squadron June 1940 S
No. 611 (West Lancashire) Squadron June 1940 S

Well quite naturally 87 fuel was predominate as the other RAF Commands (Bomber, Coastal, Training etc) used 87 fuel.

[winny]

Originally Posted by Crumpp

If it is correct, then there is absolutely no chance a single operational squadron flew with the fuel during the Battle of Britain.

luckily it's not correct. Just let me understand your argument here.

You're disregarding contemporary combat reports, pilot's memoirs, Morgan and shacklady and more, in favour of a document that was written when nobody in Europe expected the war to start in 1939. Nobody, not even hitler.



Britain was in the process of rearmament. Everything changed in September '39.
They were expecting to have to fight in '41 or '42. As soon as Poland was invaded all the plans changed.

The history of trimpell oil refinery says that according to their records there were over 300 converted spitfires and hurricanes by the end of July. They supplied the fuel, at the time. Surely their account is more reliable.

EDIT: Corrected spelling of Trimpell

[lane]

Originally Posted by winny

The history of trimpnell oil refinery says that according to their records there were over 300 converted spitfires and hurricanes by the end of July. They supplied the fuel, at the time. Surely their account is more reliable.

Close but not quite Winny:

"Bulk supply contracts for higher octane fuel were placed by the Air Ministry and it was put into widespread use in the RAF in March 1940 when Spitfires' Rolls Royce Merlin engines were converted to use the 100 octane fuel.

By May 1940, reconnaissance Spitfires had begun flying combat missions using the 100 octane fuel. By 31 July 1940, there were 384 Spitfires serving in 19 squadrons using the 100 octane fuel."

Heysham Heritage Association, The Trimpell Oil Refinery



Heysham’s position is not unique, rather it’s very much in keeping with the conventional view:





Alec Harvey-Bailey, The Merlin in Perspective, (Rolls-Royce Heritage Trust, Derby, 1983)


Alfred Price, The Spitfire Story, (Arms and Armour Press Ltd., London, 1986)


David Ross, The Greatest Squadron of Them All, The Definitive History of 603 Squadron, RAauxAF, (Grub Street, London, 2003)


W.G. Dudek and D. R. Winans, AIAA Paper No. 69-779, Milestones in Aviation Fuels, (Esso Research and Engineering Company, New York 1969.)


A. R. Ogston, History of Aircraft Lubricants, (Society of Automotive Engineers, Inc. Warrendale, PA USA), p. 12.

[winny]

Originally Posted by lane

Close but not quite Winny:

Sorry it was from memory. I underestimated

And I'd forgotten about the fact that they were converting 87 into 100 - which means that the import figures do not take into account existing 87 that was converted in the UK.

Nice.

[Glider]

This might help. This is the RAF Order of Battle as reported to FC at 09.00 on the 13th July giving squadrons, bases and the operational status, I only hope you can read them. These are the original reports posted to FC as held in the NA

The no of Spitfire Squadrons is an almost exact match for my OOB plus the Hurricane Squadrons not mentioned in the prior posting

[lane]

Originally Posted by Glider

This might help. This is the RAF Order of Battle as reported to FC at 09.00 on the 13th July giving squadrons, bases and the operational status, I only hope you can read them. These are the original reports posted to FC as held in the NA

Nice document Glider. Thanks for sharing!

[NZtyphoon]

Originally Posted by Crumpp

I agree the 800,000 ton strategic reserve requirement be built up before any squadrons convert probably comes from a pre-war estimate.

If it is correct, then there is absolutely no chance a single operational squadron flew with the fuel during the Battle of Britain. England simply did not have enough 100 Octane fuel on hand to come close to that reserve requirement.

Again, that is just speculation on my part. Morgan and Shacklady just listed the two facts we know but they were not writing a book on the history of the Oil Committee and strategic reserves.

1. An 800,000 ton Strategic Reserve was required to be on hand before a single aircraft flew operationally.

If your argument that the RAF needed to build up a reserve of 800,000 tons of 100 octane before releasing it for use is correct then the RAF never released 100 octane, because their reserves never reached 800,000 tons right throughout the war. The 800,000 ton figure was a conservative pre-war estimate of what reserves should be built up in the event that America refused to supply 100 octane

It would be interesting to find the pre-war estimates for the reserves of other grades of aviation fuel and see how they match up with war-time reserves - has anyone got the pre-war estimates for other grades?