As general aviation moves bumpily along toward a replacement fuel for 100LL, there’s a backlash brewing. Why, ask the owners of low-compression, low-output engines, do we have to settle on a single fuel? Why cant there be two unleaded fuels, a less expensive one for some users and a high-octane version for the rest? And why cant one of those fuels be mogas, which enjoyed wide popularity during the 1980s? Two-fuel systems are in place throughout western Europe, although not every airport has dual fueling. Some-usually smaller grass and club fields-have only one fuel available, while others have a 91/96 (the equivalent of 94UL) and conventional 100LL. A handful even have three fuels, since mogas has a tiny presence in Europe. But even that is becoming problematical as ethanol finds its way into the European fuel supply chain. In the U.S., resistance to a two-fuel approach centers on the distribution and refining system. Although the specifications exist for lower-octane unleaded fuels (94UL was recently approved) and the ASTM is actually considering at least one other aviation low-octane possibility, these arent seen as being viable for the U.S. market.
Wheres the Demand?
Although owners of aircraft capable of burning 94UL or its variants are beginning to make their voices heard, neither the oil companies nor the FBOs who sell the fuel are convinced there’s enough demand to make the effort worthwhile. We recently interviewed more than a dozen FBOs and flightschools to seek their opinions on installing two-fuel systems and we asked readers to tell us about their experiences with mogas as a second fuel.
Bottom line? While FBOs hardly dismiss the interest in mogas or a second fuel out of hand, theyre generally either not interested or not in a position to invest in the tankage necessary to dispense a second fuel.
“Look, this is a business,” says Ken Nierenberg, who runs a busy airport and flightschool in Prince-ton, New Jersey. “Im not going to put in another fuel tank, put up the money and not have the turnover that a gas station does. The money aint there.” Princeton moves a lot of avgas-about $20,000 in sales a month-and like most operators we talked to, Nierenberg sees investing in additional tanks as just splitting the same volume for less margin. In his view, the business case is weak.
But what about the build-it-and-they-will-come proposition? That, in fact, does work at some airports, although the return on investment may not be there.
“Were selling mogas as more of a service to tenants than anything else,” says Scott Sheets, the FBO manager at Paige Field Aviation Center in Fort Myers, Florida. “We have some light sport aircraft on the field and we wanted to move forward with a product for them that we realized wouldnt be a revenue generator initially.” We heard from several other FBOs who offer mogas as a second fuel for the same reason: service and convenience first, profit second.
In any case, making a profit on mogas is difficult because there’s no headroom on the retail price. At Fort Myers, mogas actually retails for more than avgas does: $4.01 self-service, versus $3.75 for self-service 100LL. But not all airports can afford to sell mogas as a loss leader. “Weve had reasonable interest in mogas. We have sources for unleaded fuel,” said Kurt Winker at Mid-Valley Airpark in Las Lunas, New Mexico. “But we cant get it as cheaply as the premium is across the street at a gas station,” he adds. If the on-airport price goes pennies too high, mogas users will simply buy it elsewhere and bring it into the airport in five-gallon cans or truck-mounted tanks.
“You at least have to pay for your capital; you have pay for your card fees; you have to pay your insurance. All those things chip away at your margin,” Winker explains. With the right mix of traffic, relatively high demand for mogas and a ready supply, that works at some airports. But at many, it doesnt.
“Its hard to say yes to that, to mogas. If I got a grant for the tanks, Id be all