EAA's Doug MacNair discusses the general aviation industry's avgas coalition Tuesday before attendees at EAA AirVenture Oshkosh 2010. Photo by Jim Koepnick

When the U.S. Environmental Protection Agency (EPA) earlier this year requested that the public suggest alternatives to leaded aviation gasoline, the request set off what likely will be a lengthy and complicated transition to an unleaded fuel for general aviation.

In response, a coalition comprised of general-aviation associations and petroleum-industry organizations formed with the expressed goal to develop and implement "the process by which an unleaded avgas solution will be identified."

That coalition presented an update Tuesday for EAA AirVenture 2010 attendees and reported on its plans.

The issue, of course, is minimizing or replacing the lead-more correctly the amount of tetraethyl lead (TEL)-found in existing 100LL aviation gasoline.

The EPA's request earlier this year has its roots in a 2006 petition filed by the environmental group Friends of the Earth, which essentially asked the agency to regulate general aviation's lead emissions.

In response, the EPA said it is examining whether 100LL poses a health risk and, if it does, whether that risk is great enough to mandate minimizing or eliminating it.

Importantly, there is no deadline under which the EPA is operating and no one expects the general aviation industry will one day suddenly wake up to find 100LL no longer available.

Working on a transition

Instead, the general aviation industry and the avgas coalition are working to use the EPA process as an opportunity, one designed to identify and transition to an unleaded fuel in an orderly fashion. Its work so far can be broken down into a short-term and a long-term strategy.

In the near-term, the GA avgas coalition wants to achieve net reductions in the lead released into the environment around airports. The coalition does not envision this objective will require actions by manufacturers or operators. Instead, a "drop-in" alternative to 100LL-dubbed 100ULL, for "ultra low-lead"-is being sought, one which meets the needs of all piston-engine aircraft without modifications.

Over the long run, the coalition has embraced a five-phase strategy.

First, it is convinced the FAA must be involved from the beginning and, in fact, be in a leadership position over a public/private partnership designed to identify the best solution.

The solution itself, whether an unleaded or ultra-low-lead avgas, will be defined during the second phase. This will involve developing a specification for an unleaded avgas, including a certification process allowing use of the new fuel.

As EAA's Doug McNair noted during Tuesday's meeting, the industry has never tried to certify a fuel for existing aircraft.

Instead, the aircraft have always been certified for an existing fuel.

The third phase of the avgas coalition's long-term strategy is to develop and approve a new specification for adoption by the American Society for Testing and Materials (ASTM).

In a fourth phase, according to the coalition, that resulting ASTM specification would be used to certify new production aircraft and engines, possibly in a fashion allowing use of the new fuel as well as 100LL during a transition period.

Finally, the avgas coalition's fifth long-term strategy phase involves federal regulation by the FAA and EPA of the transition to an unleaded avgas. This includes the FAA approvals and certifications necessary to ensure safe and legal operation as well as the required fuel production and distribution infrastructure.

Cooperation, coordination are key
The coalition acknowledges new or additional regulations may be required if portions of the in-service fleet cannot transition to the new fuel within a set timeframe.

As the coalition moves forward, it has agreed on three core principles.

First, safety must be assured, including ensuring aircraft performance and materials compatibility.

Second, the impact of any new, unleaded avgas on the existing fleet of small, low-powered engines and much larger, turbocharged, high-compression powerplants must be minimized.

Third and finally, a new aviation gasoline must be available at a sustainable price.

At the meeting's close, EAA President Tom Poberezny summed up the coalition's daunting task, noting, "We're all coming at this from different levels of knowledge and different perspectives. We as a community must work together to present one voice or we're not going to make much progress."

Clearly, however, many different organizations with varying priorities and concerns are watching this process very closely.

One of the coalition's challenges will be to address those concerns and, when necessary, develop appropriate responses.

That won't happen during EAA AirVenture 2010, and probably not by the time we all return here next year.

But, as a result of ongoing efforts by organizations like EAA and the avgas coalition, it will happen eventually.