Mogas: The Great Missed Opportunity


Every time I do research or reader surveys on mogas for airplanes, I come away thinking I must be living in an alternate universe. Or maybe the people I talk to are. In todays news columns, were reporting on the results of our recent avgas survey, which revealed some interesting movement in opinions toward mogas.

Bottom line: mogas negatives are down and positives are up, meaning more people say theyre interested in using it and fewer people say they wouldnt even consider it. Yet, the mogas market gains very little traction. Its not much more available than it was two years ago, when last we did a similar survey.

I have a theory to explain the shifting opinion. Some of it may be attributable to survey error, but based on the comments I read, more owners are seeing aviation as a sunset activity and although readers who took the survey have confidence that a 100-octane replacement will eventually appear, theres real worry that it wont be affordable. Thus the interest in mogas.

And the industry dithers on. EAA and AOPA have shown little or no interest in promoting mogas as an option, yet its the single most potent factor to reduce the cost of flying. On average, where mogas is available, its about $1.40 cheaper than avgas and if your airplane burns eight to 10 GPH and you fly 50 hours a year, thats up to $700 a year in savings. At some airports its more, at others, less. The savings would at least pay for a few months of hangar rent. To be fair, the alphabets havent gotten behind mogas for several legitimate reasons, one of which is the resistance of FBOs to install the tankage, knowing they wont sell much mogas.

Fair enough, I guess. But the biases against mogas are, in my view, utterly unfounded. Yes, its true it may be hard to find premium mogas without ethanol in some areas, but complaints about vapor pressure-related problems, lack of octane and engine and carburetor deposits caused by mogas are never substantiated in our surveys. I thought reader Jack Thompson put it best in replying to the survey: I’ve been using mogas for 25-plus years with nothing but good results. I’m a mechanical professional engineer, and I’m appalled at the institutional ignorance and head-in-the-sand attitude of the industry on this topic. Pure lunacy.

There may be a confluence of events that will yet inject life into mogas, however. First, Lycomings SI 1070 bulletin approves a long list of engines for mogas, provided the fuel meets certain octane and vapor pressure requirements and a new company called Airworthy Autogas proposes to make and distribute that very fuel. This should, once and for all, address at least some of the unfounded beefs against mogas. Oh, and third, Im not alone in believing the replacement for avgas, when it eventually arrives, will cost more than 100LL does now. Im guessing a buck more, so the Delta between mogas and avgas could rise to $2 or more. Airworthy Autogas will, however, cost a little more than traditional mogas, but maybe that will be a good tradeoff against its pedigree. In mogass favor is the ever-growing number of Rotax engines that can burn it, as many owners of those aircraft do. Just to be clear, no one is saying mogas will substitute for 100-octane in those high-compression or high-octane engines that require it. Thats a separate problem.

When I spoke to Airworthy Autogass Mark Ellery about mogas, he asked me if I would use it. Good question, because I suffer the same biases as many others. For the Cub, Id worry about the effects of unintended ethanol on seals and o-rings and, frankly, I hate the smell of mogas. But if I had an airplane that burned more than four gallons an hour and/or someone would dispense branded mogas-and Airworthy will be that-then Id warm to the idea. I think others might, too. By branded, I mean someones name is on the pump so I know whos providing it.

So perhaps were at a crossroads of opportunity. An aggressive company is addressing biases against mogas at a time when more expensive 100-octane-which many aircraft simply dont need-seems to be on the horizon. (Nothing is worse than presuming owners of low-compression engines have to pay more for fuel just to support a 100-octane ecosystem.)

If the economics of Airworthy Autogas prove workable, it then becomes purely a marketing and promotional challenge. Can the company and the industry promote it well enough to defeat the unsubstantiated biases against mogas in general? Will owners begin to demand it? If so, perhaps we could generate enough demand to double or triple the number of airports willing to pump mogas. And thats where Id like to see AOPA and EAA go with this idea. If the two associations could pair up in promoting mogas-if Airworthy Autogas, so be it-maybe we could get somewhere.

Otherwise, Im not sure I see any bright shining path to at least arrest the rising cost of flying airplanes, much less reduce it.

Join the conversation. Read others’ comments and add your own.