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

[41Sqn_Banks]

Hi Kurfürst, I have some questions about the "Australian document".

The reason why it is included amongst AWM papers is because the Australian Government at that time was protesting vigoriously about the continued supply of lower grade 87 octane fuel when it too wanted 100 octane for the RAAF. McFarland, Pugh, Hart, Perret, Lumsden and even Churchill have all quoted parts from the report.

Is the reason why it is included specifically stated in the document or is this a interpretation?
How do you know that the listed persons quoted from the report, where can these quotes be found?

Is the following quoted text a summary/interpretation by Pips or is this a actual quote of the document?

"The first bulk shipment of 100 octane fuel had arrived in Britain in June 1939 from the Esso refinery in Aruba. This and subsequent tanker shipments from Aruba, Curacao and the USA were stockpiled while the RAF continued to operate on 87 octane petrol. Having secured what were considered reasonably sufficient quantities of 100 octane, Fighter Command began converting its engines to this standard in March 1940, allowing boost (manifold) pressures to be raised without the risk of detonation in the cylinders. This initial increase in maximum boost from 6 lb to 9 lb delivered a useful power growth of around 130hp at the rated altitude.

By the time of the invasion of the Low Countries by Germany in May 1940 the RAF had converted approximately 25 % of it's total fighter force to 100 octane fuel use. The subsequent escalation in air activity and demands placed upon Fighter Command over the next two months put great strain on both the 100 octane fuel stockpiles and aircraft modified to use the fuel. Against the backdrop of total war the RAF found that it's reserves of 100 octane fuel was well below the level considered necessary for widespread use, for any sustained length of time.

Two actions were immediately undertaken by the British War Cabinet in May to resolve the looming crisis. Firstly 87 octane fuel was deemed the primary fuel source to be used until further supplies could be discovered and delivered in sufficient quantities to allow the Merlin conversions to again take place. Those existing fighters already so converted (approximately 125) would continue to use what supplies of 100 octane were available, but all other fighters that had not been modified to continue with the use of 87 octane (of which there was more than adequate supply). The second action was for the British Government to contract the Shell Oil Refining Company to assist the British-controlled Iraqi Petroleum Company at Kirkuk to produce 100 octane fuel. This arrangement proved quite successful as production was quickly converted to 100 octane fuel.

The first Middle East shipment of 100 octane fuel arrived in Portsmouth on 12th August, with a further two deliveries in September and four in October. Although too late to allow widespread conversion for the use of the fuel the deliveries did ensure that from this point on Britain would not be lacking in 100 octane fuel levels. With the newfound supply RAF Fighter Command again embarked upon a Merlin II and III conversion to 100 octane use from late September, finally achieving 100% conversion of it's fighter force by the end of November in 1940.

I never heard of a initial limitation of +9 boost and you just mentioned that this was already discussed. Can you give me a link to this discussion or source?

[Glider]

Your playing your game again Kurfurst only quoting one paper from a complete stream. However you believe that certain means 25%, so prove it. All you need to do is look at the strength of FC compare it to the combat reports/squadron records and you will have your 25%.

Pips clearly states
Two actions were immediately undertaken by the British War Cabinet in May to resolve the looming crisis. Firstly 87 octane fuel was deemed the primary fuel source to be used until further supplies could be discovered and delivered in sufficient quantities to allow the Merlin conversions to again take place
We know the War Cabinet didn't make those decisions so find out who did, simple request.

The other core to the Pips position is that there was a shortage of 100 Octane which caused the decision he believes the War Cabinet made. I ask you to find any reference to any paper from any official source that states that there was a shortage of 100 Octane for FC in 1940.

[camber]

I realise this thread is a bit acrimonious but overall the content has been very interesting. The technical points have already been made but I am interested in the logic of is being argued.

Kurfurst, your argument appears to be that it cannot be proved definitively that all fighter stations during the BOB used 100 octane. On that narrow definition you are quite right, especially if you hold your own personal threshold of 'absolute proof' very high.

But based on the material presented in this thread, I still consider it likely that the BOB was fought largely if not completely with 100 octane. Almost all others in this thread, and also the previous very large thread on the same topic at another forum, seem to be of the same opinion. Perhaps someone in these threads at some point has stated that ALL RAF fighters were using 100 octane by the BOB without exception, but if you are arguing against that statement, you are presenting a variation of the straw man argument...refuting the most extreme position of your opponents instead of the typical position (and declaring victory!).

Neither using or not using 100 octane in the BOB is an extraordinary claim that requires extraordinary evidence, or extra onus of proof on either side. Personally I could easily believe either of them, and have no initial bias that I am aware of. An extraordinary claim would be that the RAF had a jet squadron during the BOB, for example.

Typically when deciding between such competing ordinary claims, people examine what evidence exists and make a qualified judgement on the topic to move forward with. Seeing there is an large amount of anecdotal evidence for widespread use of 100 octane as reported in this thread, also a compelling historical reason to use 100 octane, and finally documented historic availability of 100 octane, it doesn't seem surprising to me your argument is not being taken up or accepted by others.

Going against the crowd is of course not a logical problem. If you argued against the existence of witches in the 1600s, you would be widely refuted but still correct (I hope!). But for every case like witch existance/nonexistance, there are many many more cases where the person arguing against informed peer belief is just mistaken. Of course your continuing arguing from your corner has lead to a lot of interesting technical information posted, and for that I thank you.

camber

[NZtyphoon]

And still, amongst all of his blather, KF has not presented any evidence whatsoever that the Pips memo actually exists, nor has he seen it himself except as a summary on a thread. Yet everyone who argues against KF has to provide solid, documentary evidence to back up their claim, otherwise it is dismissed out of hand.

[MoGas]

even in the current german http://www.flugzeugclassic.de/zeitsc...ft=704&nav=621 issue, the talk about 100 octan for the RAF fighters in the BoB campaign. It seems everyone is rong lol....

[lane]

There is plenty of documentation of 100 octane fuel use before and during the Battle of Britain. For starters:





602 Sqdn. Operations Record Book


611 Sqdn. Operations Record Book


151 Sqdn. Operations Record Book


74 Sqdn. Operations Record Book


111 Sqdn. Operations Record Book


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


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)


Leo McKinstry, Hurricane, Victor of the Battle of Britain, (John Murrey Publishers, London, 2010)


Leo McKinstry, Hurricane, Victor of the Battle of Britain, (John Murrey Publishers, London, 2010)


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


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


RAF History


602 Sqdn. Spitfire I


609 Sqdn. Spitfire I


610 Sqdn. - Hawkinge, July 1940

[Glider]

I know that and I thank you for your posting, but it cannot be questioned that central to the Pips position is that there was a shortage. All I am asking is for Kurfurst to provide any evidence, that any part of the UK government, any department, considered there to be a shortage of 100 octane for FC, at any time during the BOB.

There are a raft of papers to the contrary and I could add a load more to your posting but I am not asking Kurfurst for that, I am just asking him to provide one paper, just one, that says there was a shortage.

It shouldn't be that difficult, hundreds of papers, books, articles, personal memories, histories have been written about the battle. There must be one that agrees with him.

[TomcatViP]

Hi Bounder!,

The number of pages concerning the article (exception made of the 2 pages of adds) is only 3 pages p576 to 579. It seems for me that quoting the page was of no importance as I alrdy took great care of extracting for the reader AND in the same order what was the essential for the discussion.

That article was written at the occasion of the commemoration of 40 year of aero engine dev by RR and 50 years of History. The article is filled with 1 page add of RR. Obviously, we can understand that as it is today the article might hve been reviewed by RR !

The journalist of FLIGHT (H. F. K I N G , M . B . E) use a chronological order in his article and describe any major evolution of that engine IN THAT ORDER.

For example if he specified that 87 octane was the fuel grade in use at the time, when 100 oct fuel is introduced in an engine he noted the modification.

For example he clearly explains that if Hurri and Spits did rely on the Mk II and III, the Fulmar equipped with MkVIII could be fueled with 100 octane (with a max output power of 1080shp at T.O contrary to 1010 without - without meaning obviously with 87 ocatane ).

On point 1: yes we are talking abt 1937. It's the beginning of the article that deal chronologically with the Merlin story.

To say that the 87 oct fuel was the normal fuel used at that date I am using the quote on point 7 saying that using 100 oct fuel the Merlin XX had a 9lb boost
The date I mentioned (remark that I didn't re-use the 1942 date as in the FLIGHT article) is in perspective with the service introduction of that engine as in my own memory.

Note also that there is no mention of any use of the XX engine in the Spitfire but one on how the process of introducing that level of improvement was difficult ("These figures represent an
increase of nearly 250 h.p. over the Merlin II of identical cylinder
dimensions, and illustrate in a convincing manner the technical
progress achieved by years of 'toil, tears and sweat,' to borrow a
classical phrase from our worthy Prime Minister.")

All that makes sense to me on the base of technical grounds.

The quote made out of the rest of article are there to put the subsequent development in perpective regarding SHP and boost with the ultimate being 25lb for the post war 131/132 on the Hornet.

Hence we have two door in the Merlin history acording to the article : one in 1937 for introduction of 87 octane (confirmed in 1940 with the mention made of the Fulmar using a special engine) and the other in 1941 (42 in Fligt article) for possibility of 100 octane usage in the mkXX.

After that date it's upon the reader to decide witch fuel was in use since the article does not mention any switch (witch I found interesting despite all the other details of the engine modifications) but it's another story

Note also that in 1954, the merlin with 150000 units produced (all manufacturer included) represented more than 80% of all engines build by RR at the time (185000)

Source : http://www.flightglobal.com/pdfarchi...0-%201286.html

[Bounder!]

Originally Posted by TomcatViP

In the series of " What archives tells us" here is the FLIGHT archives that I cited two days ago :

- There was no 100 octane fuel usage during BoB in the FC. Here I am putting my money on British pride that would hve pushed forward any of its usage (ok Brits are not French but never the less )

- in 1941 increased power Merlin's had 9lb boost level

- 100 oct fuel was used by some aircraft in the RN (Fulmar) fitted with special engines such as the Merlin VIII (presumably to compensate for the extra weight of the 2nd crew member and low alt missions)

- In 1941 planes were still using 87 octane such as was the Hurricane with Merlin XX

Sources : (http://www.flightglobal.com/pdfarchi...0-%201286.html)

Hi TomcatVIP, interesting claim given the overwhelming evidence for widespread use of 100 Octane fuel during the Battle of Britain. Perhaps there is new counter evidence in this document? EDIT: I found you post on page 39 (post 383 of this thread) that has a working link. I don’t see anywhere in that document the statement that 100 Octane fuel was not used in the Battle of Britain, or on the contrary, that 87 Octane was used by Spitfires or Hurricanes during the Battle of Britain. Nor I could not find any mention that “In 1941 planes were still using 87 octane such as was the Hurricane with Merlin XX”.

In response to your claim in point 3 of your post (434) on page 44, and I quote you said "the petrol normally used at that time was 87 Octane" I find this slightly misleading as the time in question is 1937, which you did not state nor was there an attempt to put the quote in context. Whilst it does say on Page 557 of the original text (link) that “the petrol normally used at that time was 87 Octane” it is referring a to pre-war flight endurance test in 1937 where the Spitfire in question used “fuel of a higher Octane” (than 87 Octane). Note, this is stating that in 1937 the petrol normally used was 87 Octane – it does not mention the normal Octane used during the Battle of Britain 3 years later in 1940. I fail to see the significance of this quote regarding Octane usage during the Battle of Britain when we examine the whole quote.

If I have missed any quotes in the document regarding 87 or 100 Octane fuel usage during the Battle of Britain, and I may well have done considering it's a huge document, could you please quote them directly and list the page in the document that they appear so we may examine them in full. For example as I have done above by stating the quote and it’s appearance on page 557 with a working link to the page. Thanks.

Originally Posted by MoGas

even in the current german http://www.flugzeugclassic.de/zeitsc...ft=704&nav=621 issue, the talk about 100 octan for the RAF fighters in the BoB campaign. It seems everyone is rong lol....

MoGas, could you post a summary or even better images of the article you are referring to in english since it seems the magazine you are referring to requires a subscription.

Thanks, Bounder

[Al Schlageter]

This is what Pips said about what he found when asked: "were the British deceiving to the Australians?"

I wouldn't be surprised. The British did quite a bit of that during both World Wars.

So even Pips has his doubts about the factual truth of what he found.

(It seems that the one accusing others of being selective is himself being selective.) tut tut

There is certainly evidence that this was a deception for British stocks of 100 octane fuel was:

30th September 1939 - 153,000 tons
27th February 1940 - 220,000 tons
31st May 1940 - 294,000 tons
11th July 1940 - 343,000 tons
31st August 1940 - 404,000 tons
10th October 1940 - 424,000 tons
30th November 1940 - 440,000 tons