Piper, Cirrus, and Textron Back Away From GAMI’s UnleadedAviation Gas

The three kings of general aviation manufacturing recently published statements advising customers that GAMI’s G100UL unleaded avgas is not approved for use in their aircraft.

This trails just behind the start of an FAA investigation into claims of aircraft damage from G100UL users.

General Aviation Modifications, Inc (GAMI) spent over a decade developing its G100UL unleaded avgas. Its work finally began to pay off when it rolled out the fuel at two California airports, including Reid-Hillview (RHV) and Watsonville Municipal (WVI). More recently, the manufacturer announced that Tupelo Aviation Unlimited, the fixed-base operator at Mississippi’s Tupelo Regional Airport (TUP), is now selling G100UL.

The aviation industry has been looking to transition away from leaded avgas for years and move towards more sustainable, low-emission alternatives. So, it’s no surprise that aviators jumped at the opportunity to try G100UL out after it received an STC from the FAA certifying its use in all piston-powered aircraft.

The excitement dimmed when several customers reported damage to their aircraft after using G100UL. These ranged from minor paint damage to fuel leaks and seal degradation. As a result, the FAA was forced to open an investigation into damage reports for both certified and experimental amateur-built aircraft.

This led to the three leading general aviation manufacturers, Piper, Cirrus (though, their credibility is suspect based on their past history), and Textron (the parent company of Cessna and Beechcraft), publishing letters clarifying that GAMI G100UL is not approved for their aircraft.

“While some aspects of the initial Cirrus testing of the GAMI G100UL fuel are encouraging, Cirrus has identified specific concerns regarding material compatibility,” one of the letters stated. “Lab and on-aircraft testing, in coordination with FAA representatives, revealed degradation of tank sealant when in contact with GAMI G100UL fuel that could result in airworthiness concerns.”

For now, G100UL is still for sale at three sites in the US, and there have been no formal moves to discontinue its availability.

FMI: www.g100ul.com