We did a lot of engine testing for the Aerosonde debacle.

For reference the 20 cc 4cycle (OSmax) engine we hacked on got down to 0.5 lb/hp-hr but had real reliability problems when leaned out.

We did a lot of work later on the Zenoah G21 (21 cc 2cycle) and got sfc numbers more like 1.2-1.5 lb/hp-hr. I can check this in more detail as it is in one of my notebooks somewhere.

`The Zenoah company apparently made a number of engines up to 18 hp or so. They are advertising a new twin in the new model mags, 50cc? The model engines all use the wretched Walbro carburetors that would stress a saintly physics type like Ben even.

`Does anyone you know other than Siggy Zerweckh speak enough German to talk to Limbach or Hirth about current engines?

gup --

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