Not referenced in aircraft and engine manuals, though. Because there was a variety of 100 octane fuels which could be used. Asking for THE specification of "100 octane" is like asking for THE flavour of "ice cream". There are plenty.

No it is not.

From the January 20, 1943 Edition of the P-47B, C, and D Pilot's Flight Operating Instructions:

http://img411.imageshack.us/img411/1...cification.png

All fuel is specified by convention and by convention is part of the airworthiness instructions for the design. The aircraft's publications will list the fuel by specification that is authorized.

Yes, but not in front line fighters. ;)

Edit - ah, just noticed Crumpp is saying FC. No, not millions of gallons then. :D

There is data on 100 octane consumption by RAF FC but I don't see anything on consumption from those claiming 87 octane.

How much 87 octane fuel did RAF FC consume during the BoB?

Congrats, you just found one. I guess if you look a little bit more, you can find a dozen others, at least half of which could be used with the Merlin.

I do like the way that the big questions get ignored while attention is diverted down side streets.

The arguement seems to be the RAF couldn't use 100 octane because a manual that may or may not have an accurate date, may or may not have all the updates posted in it, didn't mention 100 Octane in one section. Maybe its being simplistic but if I have a combat report from a Spitfire Unit saying that it was used in combat then the engine had been modified to use it and it was used.

However there is no doubting that on average 10,000 tons of the stuff was consumed each month from April - July 1940. We have combat reports that say that it was used and station reports that say that they had been equipped with 100 octane. We also know that Bomber Command, Transport Command, Coastal Command, Non Operational units didn't use it until post August 1940
So if the nay sayers say that FC didn't use it, who did?

Its worth remembering that the whole of the UK only used 36,000 tons of fuel a month so 10,000 tons is just under 30% of the fuel used in the UK. Now if Crumpp can give a reply to that question with some evidence instead of just another theory then its worth paying attention to it.

Blenheim IV manual amendment 3 issued no later than January 1940 says 100 octane in the outer fuel tanks. I'd therefore disagree that BC did not use 100 octane until August 1940.

Source please.

Spitfire 1 entered service in 1938 and the reference to the Merlin II, an engine no longer in production by July 1940, indicates that this manual refers to a pre-1940 variant:








ii

Agree. In addition the papers David showed specifically mention that ca. 3-4 Bomber Command stations were only to be supplied with 100 octane fuel.

So I guess the million dollar question is who (BC Stations, FC Stations, manufacturers etc.) used and what amount of the fuel, and in what role (operational/non-operational flights, test trials).