George and others,

The Zoche Aero Diesel  http://www.zoche.de/  that was at Oshkosh for many years (and always "2 years from production") seemed to be such an elegant design.  It answered many of the concerns of the Thielert and others with light weight, low frontal area, simple design, claimed low fuel consumption, etc..  I heard it had a fatal design flaw, was it cooling or what?

Steve Colwell