Lawyer Pilot Says G100UL Does Not Void Engine Warranties

A reader who is a lawyer for a large eastern firm has offered a legal opinion on the warranty implications of the use of GAMI G100UL unleaded fuel in Lycoming and Continental engines. Last week Cirrus issued a service advisory that said it did not approve the use of G100UL in its SR series aircraft because its compatibility with materials used in the fuel systems was "inconclusive." It also suggested the use of the fuel could void the warranties on the engines. "As the GAMI G100UL fuel is a non-approved fuel per Continental and Lycoming, engines known to have run this fuel may not be covered by the current OEM engine warranty," the service advisory said.

In response to our story on the subject, the lawyer, the owner of a high-performance piston single, is disputing that claim and explains his opinion in the unedited statement copied below. We have confirmed his identity and granted his request for anonymity. We have sent the statement to both Lycoming and Continental. Lycoming has not responded. Continental has confirmed receipt of the statement but is declining comment while it reviews it. Unedited statement from the lawyer follows.

G100UL ® Avgas: Does Its Use Void A Continental or Lycoming Engine Warranty?
“On September 1st , 2022, General Aviation Modifications, Inc. (GAMI) was granted an Approved Model List (AML) Supplemental Type Certificate (STC) by the FAA for its G100UL aviation fuel product for use in every spark ignition piston engine and every airplane using a spark ignition piston engine in the FAA’s Type Certificate database.

"Specifically, in the STC document, the FAA states that G100UL avgas 'per GAMI Specification G100UL-12C-2 or later approved revision …' is found to be an 'approved fuel.' See STCs SA01967WI and SE01966WI. The FAA also determined that 'commingling is approved with ASTM Grade 100LL aviation gasoline and other gasolines with 100 MON or less, including MoGas, where those gasolines are also approved for the same make and model engines.' SA01967WI.

"The FAA is the federal regulatory agency that approves or disapproves all certificated engines through granting Type Certificates (such as engines manufactured or rebuilt by Continental and Lycoming), or by permitted changes to previously Type Certificated engines through the FAA’s Supplemental Type Certificate process.

"The Continental Motors Group warranty document, entitled 'Premium OEM Gasoline Engine Warranty,' dated November 2015 (the 'CMI Warranty'), states that '[t]his warranty does not apply to any engine, component, or part damaged or worn as a result of … non-approved fuel….' The CMI Warranty does not define either 'approved fuel' or 'non-approved fuel' in that document.

"The Lycoming Engines warranty document, entitled 'Limited Warranty: New and Rebuilt Reciprocating Aircraft Engines,' dated July 2022 (the 'Lycoming Warranty'), states that '[t]his Limited Warranty does not cover normal maintenance services, replacement of service items, costs incidental to the loss of use of the engine, or any engine or part that, in Lycoming’s sole judgement, experienced damage due to the following: … use of non-approved fuels ….' The Lycoming Warranty does not define either 'approved fuel' or 'non-approved fuel' in that document.

"A basic principle of contract interpretation is that the words in a contract are to be given their everyday meaning, unless the parties have, in that agreement, defined the terms to mean differently. In this situation, neither the Continental Warranty nor the Lycoming Warranty has defined the term 'non-approved fuel.' These words should therefore be interpreted in light of their normal meaning.

"The FAA by its STC approvals of G100UL has determined that G100UL is approved for use in every spark ignition piston engine and every airplane using a spark ignition piston engine in the FAA’s Type Certificate database. This includes all such engines made by Continental and Lycoming. The FAA has determined expressly and conclusively that G100UL is an 'approved fuel' for these engines and airplanes.

"Based upon the foregoing, the FAA’s express finding that G100UL is an approved fuel for every spark ignition piston engine and every airplane using a spark ignition piston engine in the FAA’s Type Certificate database precludes the manufacturers from avoiding warranty obligations under the Continental Warranty or the Lycoming Warranty by reason of the use of G100UL fuel alone.

"Even if it is assumed arguendo that the phrase 'non-approved fuel' is ambiguous in meaning under the warranties at issue, it is a basic legal principle that ambiguous terms should be resolved against the drafter (e.g., Continental and/or Lycoming). Therefore, even were the words found to be ambiguous, the result remains that the use of G100UL avgas does not void the Continental or Lycoming Warranty.”