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

[TomcatViP]

Guys the 100 oct justified itself whenn it comes to hve low alt extra power (short time) or increased fuel efficiency at low revs. That's why you see that kind of usage on the Blenheim.

It's not compatible with any highly charged eng usage untill the eng was specifically designed for (impeller etc...)

We hve alrdy say tht and this show that 100 oct usage by high flyng Spit makes no sense*.

Temp issue with the usage of that fuel were to be found even in 1945 with some latte war engines.

Moreover 100 oct costed twice as much as 87 oct fuel. This in pre-war doc. I think at today high soaring fuel cost you will easily imagine that this can draw attention of any war planners.

The only raison tht I see any large FC usage of 100oct is for a low alt air campaign such as to fight back to the sea any German ground force steping on English soil.

*Now the first Spits IIa reached Op unit in mid september if I do recall well. Those type being the only succeptible to hve an eng upgraded if ever they had.

[41Sqn_Banks]

Originally Posted by TomcatViP

We hve alrdy say tht and this show that 100 oct usage by high flyng Spit makes no sense*.

The only raison tht I see any large FC usage of 100oct is for a low alt air campaign such as to fight back to the sea any German ground force steping on English soil.

Fighters that need to intercept a high flying enemy first need to climb to that high altitude. It makes a lot of sense to reduce the climb time through the first 10,000 feet to a minimum by the use of highest engine power available (which required 100 octane fuel), especially if you can't detect the enemy on a long distance.

[lane]

Originally Posted by 41Sqn_Banks

Fighters that need to intercept a high flying enemy first need to climb to that high altitude. It makes a lot of sense to reduce the climb time through the first 10,000 feet to a minimum by the use of highest engine power available (which required 100 octane fuel), especially if you can't detect the enemy on a long distance.

Yes, that and take-off too.

[lane]

These documents relating to fuel requirments of the the Advanced Air Stiking Force and the Air Component, both in France during May 1940, give some idea of consumption, stocks, and how fuel requirements were calculated. As can be seen the Hurricanes used 100 octane, the Blenheim used a mix, while the Battle and Lysander used 87 octane, as did any transport, liason, visiting types etc.

[lane]

To underscore the above documentation of Hurricanes using 100 octane fuel in France please note the following:

P/O John Bushell, 151 Squadron, 18 May 1940


F/O Paul Richey, 1 Squadron, 11 May 1940


F/O E. J. Kain, 73 Squadron, 14 May 1940


P/O D. W. A. Stones, 79 Squadron, 14 May 1940


P/O R. P. Beamont, 87 Squadron, 15 May 1940


P/O F. B. Sutton, 56 Squadron, 18 May 1940


F/Lt. I. R. Gleed, 87 Squadron, 18 May 1940


F/Lt. I. R. Gleed, 87 Squadron, 19 May 1940


Sgt. L. H. B. Pearce, 79 Squadron, 20 May 1940

[41Sqn_Banks]

100 Octane Fuel. Completion of the Thornton Plant. Memorandum by Minister of Aircraft Production.

1940 Oct 30

AVIATION fuel of 100 octane content is now a necessity for operational
aircraft.
...
4. Our requirements of this fuel for 1941 are covered. But in 1942, after
allowing for purchases already made and the estimated output from Heysham
and Trinidad, we shall have to find 600,000 tons from other sources to meet our
needs. These will increase in 1943.
...
7. A decision is now necessary on whether we are to continue with the
erection of the Thornton plant.

http://www.nationalarchives.gov.uk/c...AB+67%2F8%2F81

They even thought about cancelling the construction of a new plant in October 1940. Looks like there was plenty of 100 octane fuel available.

[lane]

Originally Posted by 41Sqn_Banks

100 Octane Fuel. Completion of the Thornton Plant. Memorandum by Minister of Aircraft Production.

1940 Oct 30

http://www.nationalarchives.gov.uk/c...AB+67%2F8%2F81

They even thought about cancelling the construction of a new plant in October 1940. Looks like there was plenty of 100 octane fuel available.

Nice, thanks for sharing 41Sqn_Banks,

Apparently they decided to keep the Thornton plant -- partially for post war employment reasons. They sound almost apologetic for being awash in 100 octane fuel. "It might be that after the war not only aeroplanes but motor cars will run on 100 octane fuel.

[NZtyphoon]

Originally Posted by TomcatViP

Guys the 100 oct justified itself whenn it comes to hve low alt extra power (short time) or increased fuel efficiency at low revs. That's why you see that kind of usage on the Blenheim.

It's not compatible with any highly charged eng usage untill the eng was specifically designed for (impeller etc...)

We hve alrdy say tht and this show that 100 oct usage by high flyng Spit makes no sense*.

Temp issue with the usage of that fuel were to be found even in 1945 with some latte war engines.

Moreover 100 oct costed twice as much as 87 oct fuel. This in pre-war doc. I think at today high soaring fuel cost you will easily imagine that this can draw attention of any war planners.

The only raison tht I see any large FC usage of 100oct is for a low alt air campaign such as to fight back to the sea any German ground force steping on English soil.

*Now the first Spits IIa reached Op unit in mid september if I do recall well. Those type being the only succeptible to hve an eng upgraded if ever they had.

Then explain why many FC pilots described using the extra boost in their combat reports, right through the Battle of France and the Battle of Britain, either to evade attack, or to catch an enemy a/c, and why did Dowding issue a notice warning FC pilots against overusing the extra boost? Why were instructions issued to cover the conversions of Merlin IIIs to use 100 octane, and why did Spitfires and petrol bowsers have 100 octane stencilling?