[…]The market is responding to a very confused end user. Just look at the responses on this thread plus the recent unleaded avgas poll. Some pilots, aircraft owners, and many mechanics swear they can determine “engine damage” in aircraft engines that use non-ethanol auto-gas or mogas. That “engine damage” is never clearly defined. But they swear non-ethanol autogas or mogas is causing some sort of engine anomaly, wear patterns, with their intuition saying it is not good. Sort of an aviation urban myth. No one knows where the myth started. But by gosh, non-ethanol autogas is no good for airplane engines. The hell with the Peterson STC or EAA STC, it don’t matter how exhausting and strenuous the test(s), no matter the accumulated data over the past four decades, non-ethanol/unleaded auto fuel or mogas is no good. Period!
This is a companion discussion topic for the original entry at https://www.avweb.com/features/reader-mail/top-letters-and-comments-september-3-2021