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Mixed messages from Lycoming

By Kent Misegades · June 17, 2010 ·

There is a raging debate over the future of 100 octane avgas and Lycoming’s view about the problem on an  AVwebinsider Blog by Paul Bertorelli. The gist is that TCM thinks most of its engines would work on 94 UL, or could be made to work on it, and Lycoming says that there must be a 100 octane gasoline. Of course, this is all wrapped in the context that GA can only afford to have one avgas.

I find the Lycoming stand on 100 octane fuel and the resulting implication that there will be only one avgas and it must be 100 octane a bit specious. Does anybody else remember this announcement on AVweb on June 4, 2008, and the forum presented by Lycoming at AirVenture 2008 on Tuesday, July 29, called: Lycoming Activities on Alternate Fuels-The Future, given by Randy Jensen, and the resulting flurry of articles surrounding the announcement of the Lycoming O-233 LSA engine.

At the AirVenture forum on avgas, Jensen explained what Lycoming was doing with the mogas announcement for the O-360 and IO-360. Jensen, who sits on the ASTM fuels panel, explained that Lycoming was proposing a new 93 AKI unleaded mogas fuel standard, as part of ASTM D 4814 (mogas), for aviation use. He indicated that it would be a special blend of mogas with tighter RVP standards and a few other tweaks. He said that Lycoming specifically picked the O-360 and IO-360 for this program because they were the most ubiquitous engines in GA and Lycoming figured that market forces would prevail. Since then, nothing. Deafening silence.

Jensen gave another presentation at AirVenture 2009. No mention of 93 AKI mogas. So I asked him about it during the Q&A session at the end of his presentation, and why Lycoming wasn’t just supporting the ASTM 94 UL standard. He indicated that the 93 AKI standard was still a high priority at Lycoming but they just got too busy with other projects but it was going to be done and that it was different than 94 UL.

What is ironic is that back in June 2008 Lycoming expected FAA approval by the fall of 2008. To date nothing has been submitted to ASTM and there have been no further announcements by Lycoming.

Of course, what really begs the question, is how would such a special gas be delivered? This new fuel would require the dreaded, we must never speak about it because it can’t be done, two tank solution on our airports.

Submitted by Dean Billing

The GAfuels Blog is written by three private pilots concerned about the future availability of fuels for piston-engine aircraft. They are:

  • Dean Billing (Sisters, Ore.) – an expert on autogas and ethanol
  • Kent Misegades (Cary, N.C.) – an aerospace engineer and aviation journalist
  • Todd Petersen (Minden, Neb.) – former aerial applicator and owner of more than 150 Mogas STCs for aircraft

For a list of airports that have ethanol-free fuel and those no longer pumping it, compiled by the authors, follow this link.

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