A Federal Aviation Administration (FAA) committee in the USA has released a final report into plans to replace 100LL avgas with unleaded fuel, concluding that there is no “drop-in” solution, and may actually be technically infeasible.
The conclusion of the Unleaded Avgas Transition Aviation Rulemaking Committee (UAT ARC) has not cooled the determination of the US Environmental Protection Authority to get lead out of avgas regardless.
UAT ARC was formed 18 months ago to study the issue with the goal of starting the transition toward unleaded avgas by 2018, but the final reports calls for an 11-year time frame or more to change away from 100LL.
Depending upon the alternative fuel developed, there is a possibility that systems on some aircraft may have to be changed, making the transition a very expensive proposition.
Despite the initial pessimism in the findings, the UAT ARC remains confident a solution will be found, and the FAA is continuing the project by establishing the Piston Aviation Fuels Initiative (PAFI) to develop an unleaded avgas.