Art W. writes: “GAMI says it meets ASTM D910 (100LL) for detonation and D909 for full take off power (equiv to 115/145 Avgas), yet in Q30 asking about ASTM certification GAMI states, “No. GAMI elected to use the existing and approved STC
pathway to obtain approval for our general aviation aircraft and engines to use G100UL avgas.”
The FAA can be good at dragging issues out. Failure to give them something to lean on, like compliance data in the form of ASTM consensus standards, ensures it will drag forever. GAMI argued the ASTM standard was flawed and that their findings were more acccurate. Maybe so, maybe not. But the FAA is anything but dumb, and just because an applicant says it’s so, doesn’t mean it is.