Spit IIa is now so much more inferior to the 109

[41Sqn_Banks]

Originally Posted by Kwiatek

So for Merlin III at 87 octan fuel we have:

max take off - +6 1/4 at 2850 RPM

...

So with Merlin III at 100 Octan we have:

take off - +6 1/4 at 3000 RPM

It's interesting to note that publications from 1938 and 1939 give maximum take-off engine speed of 2850 rpm for both Merlin II and III. Publications from 1940 give 2850 for Merlin II and 3000 rpm for Merlin III. The increase is not associated with the use of 100 octane fuel.