In article ,
Cougar wrote:
Somebody on another forum was trying to convince people that
because of the gasoline shortages during WW-II that there were
quiet a few aircraft that actually used diesel fuel.

I know that people are playing with that today, but was it
really used in aviation back then?

More pre-WW2 than during: the Germans were keen on lightweight
(for some value of lightweight) 2-stroke aerodiesels, using
them in several flying boat designs. These Junkers opposed-
piston designs were licenced pre-war by Napier (as the Culverin)
but they never saw much use in .uk
During the war - well, /particularly/ for the germans considerations
of absolute fuel economy soon became secondary to improving performance
so aerodiesels fell out of use for all but maritime patrol a/c which
might expect to be operating away from fighter opposition - the
Dornier 18 and the Blohm und Voss 138(? the 3-engined flying shoe)
continued to use diesels until the advent of the escort 'carrier
saw an end to their activities.
The allies (and the italians, and the japanese) never really
bothered with aero-diesels for warplanes, for fairly obvious
reasons.
Post-war there was nearly a come-back, with the Napier Nomad
turbo-compound (a hybrid diesel-gas turbine engine, with the
diesel driving the compressor stage) proposed for an evolution
of the Shackleton. I believe it's still the among the most
fuel-efficient engines ever built, but it never went into
production.

--
Andy Breen ~ Interplanetary Scintillation Research Group
http://users.aber.ac.uk/azb/
"Time has stopped, says the Black Lion clock
and eternity has begun" (Dylan Thomas)