General Aviation Modifications, Inc. (GAMI) is now selling supplemental type certificates (STCs) for its G100UL high octane unleaded avgas—the first and only approved solution for all general aviation piston aircraft.
In order to purchase the STC, pilots will need aircraft and engine information including N-number, aircraft model and serial number, and engine manufacturer/serial number. STC documents will then be delivered via PDF immediately and placards will be mailed within about 10 days.
As an early adoption incentive, pilots who purchase the STC on or by March 31 will be eligible for a “First Fill Up Rebate” of $100. According to GAMI, customers can submit a copy of the first G100UL high octane unleaded avgas purchase receipt from the FBO when the fuel becomes available in their area.
“The FAA approval of G100UL high octane unleaded avgas is a truly huge development for the future of general aviation!,” said GAMI president Tim Roehl. “GAMI and all of its employees have dedicated themselves to this project for over a decade. Now is the time for all of the stakeholders in the general aviation community to stand up and celebrate. These AML-STCs are the ‘beginning of the end’ for the continued use of lead in aviation gasoline.”
While costs for the G100UL STC vary depending on aircraft engine and horsepower, GAMI says pricing will be roughly the cost to fill up their tanks with avgas. For aircraft such as a Cirrus SR22, Piper PA-32, or Cessna 210, the STC will be around the $600 range.
How Much Will the Fuel Cost?
As far as the fuel itself—GAMI estimates a price slightly higher at about 60-85 cents/gallon more than the current 100LL. And while that may be off-putting to aircraft owners, the costs will likely be offset by lower maintenance bills. G100UL offers a cleaner fuel burn and improved spark plug maintenance and replacement intervals without lead, according to the company, which also expects oil change intervals to double over time.
Although the FAA signed off on G100UL in September, initial rollout of the fuel won’t begin until later this year—starting with California. GAMI anticipates all West Coast states to roll out the fuel by 2024, with national availability by 2026. Flight schools will likely be the first to test the fuel ahead of widespread distribution.
The industry’s goal to safely eliminate the use of leaded aviation fuel by the end of 2030 remains on track, though some states have voiced their concerns that it’s not soon enough. In January, California’s Santa Clara County banned the sale of 100LL, while Washington state recently introduced a bill that seeks to do the same, albeit statewide. Additionally, Colorado’s Boulder County recently agreed to join local governments across the country in supporting the Environmental Protection Agency’s finding that leaded gas endangers public health.
Calls for premature elimination of avgas by activists and some city officials has become more prevalent— drawing backlash from several aviation groups who believe the transition needs to be done safely and efficiently. Any rushed decisions to eliminate avgas would result in negative consequences for the GA fleet and hinder progress on the initiative.