Bill Daniels wrote:


You know, I just don't buy the "skin radiators won't work" theory. The
pre-war Schneider Cup Seaplane racers did use skin radiators to cool some
really big engines. There are LOTS of reasons skin radiators weren't used
on WWII fighters - bullet holes being one. Since then, piston aero engines
have been air-cooled.

I don't either.

A diesel fuel-cooled plant would NOT use raw fuel in its coolant
passages. It would have a conventional glycol "primary loop", with a
radiator-behind doors or (in front of) cowl flaps, a cabin heat
exchanger ("heater core" in autoese), and an intercooler with fuel
circulated through it and returned to tanks. It would be designed so
the fuel loop could be shut off-bypassed- when the rad had its doors
open as would be done when the aircraft was very low on fuel, or in
high thermal load situations.

At altitude (this is a turbodiesel and flies at high FL) the ambient
temperature is very cold and the normal radiator could be blanked off
largely or entirely. If the tanks are designed with a lot of surface
area they will cool a large percentage of the engine's total heat
rejection and additionally provide anti-icing.

The main requirement as I see it is the system has to be default
failsafe and provide single lever power control. Unless you want to
make it a two person flight crew aircraft and haul a FE along.