Misconceptions about the 100LL replacement conundrum

There are a number of media reports, websites and blogs here and there about the transition process to an unleaded 100 octane avgas, which illustrate two serious misconceptions of the aircraft owners who must have 100 octane avgas. Until these misconceptions are addressed honestly, GA is going to tear itself apart.

Misconception 1: The amount of 100 octane avgas that is used or needed by GA is not known accurately. The worn-out statistic that is always thrown out in the press and at meetings needs to be challenged and then replaced by accurate numbers. This is the statistic that is oft repeated, “While these operators represent about 30% of the general aviation piston fleet, they consume about 70% of the fuel.” It is very important for those start-up companies that might be planning to make a 100 octane replacement that the consumption statistic by target audience be accurate, but this statement isn’t accurate. Nobody knows exactly where it came from, but it has been repeated over and over for almost a decade, that I know of, in the aviation press. That doesn’t make it true!

First, what we really know: The amount of 100LL used has declined every year for the last seven or so years. Look at the EIA stats from DOE. Avgas usage has been declining an average of about 7.5 million gallons a year. In 2009 it appears that about 180.4 million gallons were used.

Second, the FAA keeps publishing stats that claim we are using 300+ million gallons of 100 LL a year. A chart that showed up in an April 1, 2009, presentation — a date which might be prophetic — by the FAA sort of shows that “Lower Performance Airplanes” make up 75+% of the aviation fleet and it appears they use more than 30% of the fuel, and the chart states that GA uses 350 million gallons a year.

I believe a more accurate figure was stated by the General Aviation Manufacturers Association (GAMA) at the fuels forum presented by EAA at Airventure 2009, which was that about 20% of the GA fleet probably uses about 50-60% of the 100LL fuel. This figure makes more sense, but what is obvious about all of these charts and presentations is NOBODY REALLY KNOWS how much 100 octane gas we use and how much we need.

So here is the problem: Let’s say GA actually uses closer to the EIA stat of less than 200 million gallons a year, which we know is declining because everybody agrees about that. And let’s say that 80+% of the GA fleet that is using 40% of the fuel could be using premium unleaded mogas today. That means that we only need about .6 x 200 million = 120 million gallons of 100 octane avgas a year. Even at 70%, that means we would only need 140 million gallons of 100 octane avgas — and remember demand is declining! Swift and GAMI need to pay attention to these numbers. Swift said at Sun ‘n Fun that they were targeting a production need of 300 million gallons a year. Somebody better figure this out pretty soon or there are going to be a lot of bad economic decisions made.

Misconception 2: Just because every GA aircraft could use 100 octane fuel, that doesn’t mean we should, and that doesn’t lead to the prevalent idea that there will be, or should be, only one avgas which, ipso facto, has to be 100 octane. This is absurd logic.

“The very small relative market that aviation gasoline represents (0.1% of all transportation fuel) will dictate only one unleaded fuel solution, not multiple grades. A dual-fuel approach is not viable. This conclusion is re-enforced by the fact that there is typically only one tank for avgas at the airport.” While the avgas market is truly boutique, it does not logically follow that a dual-fuel approach is not viable; you certainly can’t reach that conclusion just because there is one avgas tank on most airports. That is the epitome of fallacious reasoning, especially when another viable avgas is already being made today.

What is ironic is that the unleaded fuel that 80+% of GA is made today, is ubiquitous and has the lowest delivery cost of any fuel because it needs no special handling, premium unleaded auto gasoline made to ASTM D4814, an approved aviation fuel. Just because there is “typically only one tank for avgas at the airport,” that has been neither historically the case nor is it a real economic impediment. Modular self-service tanks and pumps can be installed. If GA had anywhere near the cahones of the ethanol industry, they would get the GA caucus to get the kind of subsidies and tax incentives that the ethanol lobby gets for E85 fuel infrastructure, which also doesn’t exist today. That doesn’t stop the ethanol lobby from getting your tax dollars to build their infrastructure and force their product on you. (Although that does kind of remind me of the tactics being used now by the 100 octane crowd that wants to force that fuel on every airplane owner.)

“Further, it is my opinion that there was a consensus at this meeting that a sub-100 octane fuel is not a viable solution and that all resources should be directed toward developing a full 100 octane solution that will have the least overall economic impact on the fleet and the industry.” How can a 100 octane solution that will cost at least as much, if not more, than 100LL today have the least economic impact on the 80+% of the pilots that don’t need 100 octane avgas? This is an arrogant conclusion. When a large segment of GA doesn’t need 100 octane gasoline, why shouldn’t they be getting the proper fuel recommended for their aircraft at the market price of that fuel, especially when it is already in production everywhere?

Note: Quotations in above text are from Malibu-Mirage Owners & Pilots Association Report to Membership, June 20, 2010, but similar statements are made by a number of organizations representing aircraft owners that need 100 octane avgas for their aircraft.

Submitted by Dean Billings.

The GAfuels Blog is written by two private pilots concerned about the future availability of fuels for piston-engine aircraft: Dean Billing, Sisters, Ore., an expert on autogas and ethanol and Kent Misegades, Cary, N.C., an aerospace engineer and aviation journalist.

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


    1. says

      Victor- I think that if you look at Continental’s announcements lately they are indicating that most all of their engines will work on 94 UL and that new engines will be designed for it so that they will not be constrained to an avgas that is very difficult to make without TEL, which is going away, either by EPA edict or because the one company that makes it decides that there is not enough demand to continue making it, which is more likely. Lycoming is pretty much taking the opposite stance and demanding 100 octane avgas. That is why there is a lot of editorial controversy on the web about the 100 octane replacement.

    2. says

      According to this article you don’t need lead: http://www.kitplanes.com/magazine/pdfs/0606-2935.pdf
      Just a fuel truck is problematical. They must be driven on the road by a qualified driver. They are difficult to insure by themselves. Most fuel trucks are supplied from an on-airport fuel farm so they don’t have to be driven on public streets, so you end up needing a tank anyway. Might as well install a complete self-serve fuel system. Your last question is a good one, and others are proposing it, especially when 94 UL is approved. We will be outlining the costs and procedures for installing a self-serve fuel system at our forum at AirVenture 2010, the presentation slides will be uploaded to http://www.flyunleaded.com as soon as they are ready.

    3. j letourneau says

      For a list of gas stations that sell E0 (ethanol free gas) go to pure-gas.org. I’m still mixing my E0 with 20% 100LL to get the nominal amount of lead for lubrication or the valves and as a valve set cushion on my 80/87 Octane low compression aircraft engines (and I have the Petersen Auto gas STC). If Premium auto gas was available I would be burning it all the time when out on trips, but since it isn’t I am forced to use 100LL. We could cut the use of 100LL in half if we weren’t forced to use it in the low compression fleet. What would the cost of another fuel truck that could be filled with E0 really be at most active airports, for that matter many airports have more than one fuel service, why wouldn’t one of them specialize in each fuel instead for both competing with 100LL and nobody selling enough to make a profit.

    4. VICTOR ONEILL says

      Why do Lycoming and Continental continue to manufacture engines that can only survive on 100 LL?

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