EAA Addresses G100UL Use In E-AB Aircraft

Association notes that Experimental-Amateur Built aircraft are not included in STCs.

Credit: GAMI

Last week, the Experimental Aircraft Association (EAA) weighed in on the controversy surrounding G100UL unleaded aviation gasoline from General Aviation Modifications Inc. (GAMI). As an advocacy group for Experimental-Amateur Built (E-AB) aircraft, among others, EAA’s statement focused on specific concerns for E-AB builders and operators.

While EAA noted that G100UL has been authorized for use in “most certified aircraft” through the Approved Model List Supplemental Type Certificate (AML STC) process, EAA reminded its members, “It is important for owners of E-AB aircraft to remember that STCs only apply to type-certificated aircraft. E-AB aircraft do not have type certificates and, thereby, are not covered by an STC.” The statement also noted that some materials used in E-AB aircraft are different from those found on certified aircraft and it’s possible those materials were not considered in granting the STC. “Testing protocols for STCs are proprietary, and to date a list of materials tested has not been shared with owners and operators,” EAA wrote.

Among the components cited by EAA as of concern are fuel tank sealants, gaskets, O-rings and hoses as well as any other materials that could come into contact with the fuel either through normal operation or in the event of a spill or leakage.

EAA provided links to information made available from GAMI on installation instructions, instructions for continued airworthiness and routine refueling hygiene.

Mark Phelps is a senior editor at AVweb. He is an instrument rated private pilot and former owner of a Grumman American AA1B and a V-tail Bonanza.