NATA Clarifies Points on Commercial Sale of Unleaded Avgas

Recent media articles have disregarded key points outlined in NATA’s latest white paper and mischaracterized its intent. The goal of Factors Affecting the Commercial Sale of Emerging Unleaded Aviation Fuels is to educate both aviation and community stakeholders on the dynamics of the commercial availability of unleaded avgas, including considerations on the status of UL fuels, paths to authorization, and safety concerns such as materials compatibility and misfueling.

NATA’s work is tied to its mission to empower the safety and success of aviation businesses, which includes describing the operational environment and needs of FBOs, airports, fuel suppliers, and end users in fostering a safe and successful transition to unleaded aviation fuels.

One concern addressed in NATA’s white paper is industry testing of fuels and their use in all fuel-wetted surfaces throughout the supply chain. While the FAA’s STC process approves the use of fuels inside an engine/airframe, the Agency’s responsibility stops there. The FAA’s STC approval process does not consider commercial aspects of fuel properties related to global supply chain risks, fuel intermixability, issues impacting indemnities or product liability, or factors impacting materials compatibility in the supply chain. Historically, the testing of this broad range of aspects has been achieved by following ASTM International D7826 guidelines for approving an unleaded fuel – which is a precursor to earning an ASTM International fuel specification.

Just as aircraft owners and operators need assurances that the use of an alternative fuel will not compromise the integrity of any component of their aircraft nor void applicable warranties, the same is true for OEM engine manufacturers, fuel distributors, transport companies, airports, and FBOs. Businesses across the entire aviation supply chain rely on ASTM International specifications to minimize or eliminate the potential for degradation or contamination of either the fuel itself or the equipment used to transport, handle, and dispense it. The FAA does not certify fuels nor indemnify their use in the marketplace under the STC process. Instead, the Agency approves the use of fuels in those specified engines/airframes that have been issued as part of the STC process. Further, under the Fleet Authorization process, the publication of an ASTM production specification is an integral component. The ASTM International review process includes a collection of subject matter experts comprised of industry/OEMs to ensure that fuels are ready for use in the marketplace.

“Our white paper was crafted with factual input from member companies and peer reviewed by our GA Fuel Handling Subcommittee. For NATA’s FBO and fuel distributor members, an industry consensus standard such as ASTM International is an especially relevant component in bringing new fuels to market, as it evaluates compatibility with materials throughout the supply chain upstream of the aircraft,” stated NATA President and CEO Curt Castagna.

An additional concern is the compatibility of emerging unleaded fuels. While the FAA STC process has tested unleaded fuels against 100LL in the wings of aircraft, the FAA currently does not address the compatibility of mixing different unleaded fuels in aircraft, airport storage tanks, or refuelers. Further, the FAA has yet to communicate their role in testing the compatibility of unleaded fuels coming into the marketplace other than the assurance of an adequate detonation margin related to a fuel’s compatibility with 100LL. Testing intermixability of new fuels only after they enter the marketplace represents a new risk for the global aviation industry, disregarding the decades-long practice of earning an ASTM International specification along with the FAA engine/airframe certifications before commercializing new fuels in the marketplace.

Another concern is the issue of liability for aviation businesses selling fuels within the market. Most major aviation fuel distributors offer their customers umbrella liability protection of at least $50 million USD. This coverage has been offered under the assurances that come with an industry consensus standard such as ASTM International and a proven performance track record in piston engines/airframes. With current unleaded fuel alternatives still in the early phases of demonstrating performance, a published industry consensus standard is all the more relevant.

And while the issue of insurance should not be a limiting hurdle, the risk and indemnity needs associated with a proprietary fuel specification without an industry consensus standard is a legitimate point of discussion. Aviation businesses that sell fuel will likely expect similar risk liability and insurance protection for any new fuels.

NATA’s goal remains clear: the safe and effective transition to an unleaded future, which includes educating stakeholders on the complexities of the decision to sell new fuels approved with only a proprietary specification. Also key to our collective success for a safe fuel transition is protecting our members and the industry from legislative efforts to prematurely ban 100LL before an unleaded replacement fuel is commercially viable, with ample consideration given to all factors that contribute to commercially viability. Such actions would ground thousands of GA aircraft and threaten the future of our vital industry.

Individual fuel suppliers, distributors, and airports consider multiple factors when determining if a fuel is commercially viable, including but not limited to the:

  • Product’s authorization or approval for use in specified engines, fixed wing aircraft, and rotorcraft (pursuant to Supplemental Type Certificate [STC] or another FAA program);
  • Percentage of the active, piston-engine, certificated and non-certificated, fixed- and rotor-wing fleet operating out of the specific airport that can use the fuel;
  • Availability of a published industry consensus standard detailing specific requirements for the quality and safe use, production, and distribution of the fuel;
  • Sufficient quantity of active fuel production to ensure consistent availability through an established distribution network;
  • Sufficient risk mitigation protection with established product liability insurance coverage as currently provided to airports and Fixed Base Operators (FBOs) selling 100 low-lead (100LL); and
  • Product’s ability to be purchased by any interested party without restriction throughout the country.

Ultimately, it is up to each FBO and airport that provides fuel to the wing of aircraft to work with their fuel supplier to determine their risk and liability threshold for purchasing and selling emerging fuels.


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