Subject: Re: RE: Diesel Aircraft
Actually, it's strange that more diesels haven't been used in
planes. The low
revving powerband is ideal, most auto-gas engine conversions have to use
a gear rpm
reducer for the prop, since they badly lose efficiency over 2000 rpm. I
suppose
weight is a factor, but there have been plenty of aircooled diesels,
and, in recent
years, any number of water-cooled auto engine conversions.
Many German aircraft of 1930-1945 were powered by the Junkers "JuMo"
opposed piston two-stroke diesels in various sizes, with and without
turbo-supercharging, including the Ju88 high altitude, high speed
bomber. These were liquid cooled. Oddly enough, though the Deutz
aircooled diesels have done well on the ground, the only aircooled
aircraft diesels I know of are the Packard and Guiberson engines, both
technically successful but neither successful in the market. The Packard
was used in setting an endurance record in the "Question Mark," though.
The first Pratt and Whitney turboprop powerplant was also an opposed
piston diesel in a sense - the PT-1 used a free-piston gas generator
operating on the Diesel cycle to provide hot gas to the propulsion
turbine.
Recently, Renault was supposed to be working on an aeronautical diesel
plant, but I have no further info. Zoche in Germany seems to have failed
to achieve certification.
A friend of mine did a preliminary design study on a long-endurance
personal aircraft using two converted VW Rabbit (Golf) diesels - the
numbers looked very nice. Then we both got involved in other things. I
still have the notes on file. Basically, though, diesels make good sense
for low speed, long endurance aircraft.
Marc de Piolenc
Biofuel at Journey to Forever:
http://journeytoforever.org/biofuel.html
Please do NOT send "unsubscribe" messages to the list address.
To unsubscribe, send an email to:
[EMAIL PROTECTED]
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
