Ron Natalie wrote:

Petersen used to have a list of airframes tested and failed but I can't find it.

It's now buried in the text. Click on the word "airframes." The URL is
http://www.autofuelstc.com/autofuels...Airframes.html

Still, they have a note there to call them if you don't see your plane listed.
Apparently they have STCs for some aircraft that are rare.

George Patterson
The desire for safety stands against every great and noble enterprise.