The Federal Aviation Administration (FAA) has shared with the public the “Draft Unleaded Aviation Gasoline Transition Plan,” which outlines the main elements of its strategy to eliminate leaded aviation gasoline by the end of 2030. The 77-page document emphasizes that the transition process could lead to operational challenges and that decisions made by the industry will directly affect the process.
In the FAA report, attention is drawn to the diversity of aircraft and engine designs, stating that “due to the wide range of aircraft and engine designs, materials, and operations, there is the potential for challenges to arise in service.” The document also notes that decisions taken by the private sector and individual aircraft owners will be decisive for the final transition.
100LL (100-octane low-lead) aviation gasoline, which has been used in the aviation sector for many years and contains tetraethyl lead, remains the only transportation fuel in the United States that still contains lead. While this additive increases octane and prevents engine knocking, it is also criticised for causing air pollution and posing risks to human health.
The FAA emphasises that technical requirements make the transition complex, stating that unleaded alternatives must undergo comprehensive testing in terms of performance, detonation resistance, material compatibility, durability, and maintenance impacts. In addition, market conditions such as fuel availability and quality control are among the major obstacles facing the process.
The agency’s primary objective is to ensure that the approximately 175,000 aircraft in the United States that are currently approved to use 100LL can safely operate on unleaded fuel.
The transition plan consists of four phases. In the first phase, approval and comparison processes are being carried out for potential unleaded fuel options. The FAA announced that three different unleaded fuel alternatives are currently at various stages of the approval process.
In the second phase, cost analyses will be conducted and field experience from operators who transition early to unleaded fuel will be evaluated. According to the FAA, the biggest concern of aircraft owners is that operating costs should not increase.
In the third phase, the use of leaded aviation gasoline will be ended in all US states except Alaska by the end of 2030. In the fourth and final phase, Alaska is planned to complete this transition two years later.
