"John Galloway" wrote in message
...
There is also the Zoche radial 2 stroke engine:

http://www.zoche.de/

The Zoche web site has been dormant for several years. I haven't heard
anything new about them since about 1998.

BTW, reading the Diesel Air Ltd. site about the ducted fan dirigible
application, they say that they get 8 pounds of static thrust for each HP.
If 100 HP = 800 pounds of thrust, that stacks up pretty well against a 235
Pawnee that only produces about 390 pounds of thrust. That would be good
for avoiding wing dropping.

Bill Daniels