EAA, Other GA Associations Welcome GAMI’s Unleaded Fuel STC

July 28, 2021 – EAA, AOPA, and GAMA congratulate Oklahoma-based General Aviation Modifications, Inc. (GAMI) on receiving the FAA’s approval of a supplemental type certificate (STC) for its G100UL unleaded aviation fuel for use in certain Lycoming O-320, O-360, and IO-360 piston engines.

The STC for use of GAMI’s proprietary high-octane unleaded avgas, G100UL, is currently for a limited number of normally aspirated four-cylinder engines and is a constructive step forward in the development of an unleaded avgas.

The general aviation industry’s ultimate goal is an FAA fleet-wide authorization for a practical unleaded avgas that can replace 100LL with no negative impact on safety and the general aviation community.

“This STC is a positive step as we seek a fleet-wide solution for an FAA approved unleaded fuel,” said AOPA President and CEO Mark Baker. “We look forward to learning more about how the STC will be used, and next steps in expanding the number of engines that can safely take advantage of it.”

“We commend GAMI for its hard work and commitment to producing a high-octane unleaded avgas and support its continued testing on a broader range of engines and airframes,” said GAMA President and CEO Pete Bunce. “While this STC is a start, demonstrating the safety and viability of a high-octane fuel as a replacement for 100LL requires significant testing on high performance engines, as well as certain airplanes and helicopters at the most demanding boundary of the performance envelope encompassing the existing fleet of aircraft.”

“We appreciate GAMI’s long-standing commitment to addressing the immense technical challenges of replacing leaded high-octane avgas with an unleaded solution intended to satisfy the safety and performance needs of the fleet,” said EAA CEO and Chairman of the Board Jack J. Pelton. “This STC is a positive first step, and we look forward to GAMI’s continued efforts to add additional engines and ideally working toward a path for fleet-wide authorization.”

EAA, AOPA , and GAMA have partnered with the FAA and other industry associations in establishing the Piston Aircraft Fuels Initiative (PAFI), to reach the goal of a safe and viable unleaded avgas that could replace 100LL and maintain the utility of the existing fleet of GA aircraft.

PAFI provides an avenue to test and evaluate potential fuel candidates against the safety and airworthiness needs of the existing fleet of engines and aircraft. There are currently other fuels being evaluated as potential replacement candidates. The PAFI process is available to all fuel offerors to provide both an efficient means for technical support from key stakeholders, as well as to help enable a timely, cost-effective approach to address the entire fleet through an FAA fleet-wide authorization.