Centennial Airport Marks Two Years as Colorado’s First and Only Airport Offering Unleaded Aviation Fuel

    May 2, 2025
    Centennial Airport's adoption of Swift UL94 unleaded aviation fuel marks a significant milestone in environmental sustainability and industry-wide efforts to eliminate lead emissions. The program's success and support reflect a commitment to environmental sustainability and industry-wide efforts to eliminate lead emissions.
    Centennial Airport
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    Centennial Airport is proud to celebrate the two-year anniversary of its pioneering Unleaded Aviation Fuel Program, becoming the first airport in the state of Colorado to offer Swift UL94, a FAA-approved unleaded aviation fuel for piston aircraft.

    Since May 3, 2023, UL94 has been available at the jetCenters of Colorado – Centennial location. Centennial Airport’s transition to unleaded fuel began with a resolution passed by the Arapahoe County Public Airport Authority Board of Commissioners in March 2023, authorizing incentives to accelerate the switch from 100LL (low-lead) to FAA-approved unleaded alternatives.

    As part of the airport’s initiative, Centennial offers:

    • A Supplemental Type Certificate (STC) Reimbursement Program, reimbursing up to $110 per aircraft to cover the cost of FAA approval for using UL94.
    • A fuel subsidy program that bridges the price gap between 100LL and UL94 for fuel suppliers and users.

    To date, the airport has reimbursed 105 STC applications and has seen UL94 account for over 20.5% of all aviation fuel for piston aircraft sold at Centennial Airport since its introduction (Jet A, used in turbine aircraft, is already unleaded). Prior to receiving state support, the airport independently invested over $304,000 in fuel subsidies and STC reimbursements.

    The program’s success has helped position jetCenters of Colorado at Centennial Airport as the largest FBO user of UL94 in the country, a testament to the commitment from both the airport and its tenants.

    Centennial Airport’s leadership has also been recognized by the Colorado Aeronautical Board (CAB), which approved two discretionary grants—$300,000 in 2024 and $350,000 in 2025—to further support the airport’s fuel subsidy program. These grants were made possible by Colorado House Bill 24-1235, signed into law by Governor Jared Polis in May of 2024, which authorized the CAB to distribute funding for unleaded aviation fuel initiatives. Centennial Airport contributed a 10% match to both grants, reinforcing its financial commitment to the transition.

    “Environmental sustainability is a key priority at Centennial Airport,” said Mike Fronapfel, airport CEO. “This program is our way of supporting industry-wide efforts to eliminate lead emissions without compromising aircraft performance or safety. It also reflects our commitment to listening to the concerns of our surrounding communities and responding with meaningful action.”

    The initiative aligns with the FAA’s EAGLE (Eliminate Aviation Gasoline Lead Emissions) initiative, which seeks to eliminate leaded fuel in piston-engine aircraft by 2030. Swift UL94 is a FAA-approved, drop-in-ready unleaded aviation fuel that meets or exceeds ASTM standards, offering identical density and performance to 100LL without the environmental drawbacks of lead.

    For more information about the Unleaded Aviation Fuel Program at Centennial Airport, visit www.CentennialAirprot.com/UL94