In a move that is being seen to impact general aviation world-wide, the US Federal Aviation Administration published a draft plan last week to phase-out 100LL avgas in most of the USA over the next five years.
If adopted as written, the main fuel used in GA, 100LL avgas, would become unavailable in the US by 2030, with Alaska having a deadline of 2023.
However, Australia's sole manufacturer of avgas, Viva Energy, believes the phase-out will have little impact on 100LL supplies in Australia.
Driving the phase out is the 2024 FAA Reauthorization Act, which directs the FAA to work with the aviation community and stakeholders in the USA to eliminate the use of leaded fuels by the end of 2030.
"As of Fall [Autumn] 2025, 100-octane low lead (100LL) is the most used avgas for spark ignition piston-powered aircraft," the FAA states in the draft plan. "Many piston-engine aircraft designs are best suited for 100LL.
"However, in response to the evolving market factors and public health considerations, the FAA has initiated transition efforts from 100LL to unleaded aviation fuels."
Among the market factors cited is the rise of jet fuel for use in turbines and diesel piston engines, with some manufacturers reportedly adjusting production volumes to match demand.
The directive also obliges the FAA to work with industry in developing unleaded aviation fuels for piston engines. Currently there are three UL fuels at various stages of development: GAMI G100LL, Swift 100R and LyondellBasell/VP Racing UL100E.
The FAA has proposed four phases for the elimination of 100LL:
- fuel authorisation and comparison
- market experience
- national transition (by end 2030)
- Alaska transition (by end 2032).
FAA estimates put the 100LL consumption in the USA at 682 million litres per year, the loss of which has the potential to encourage avgas manufacturers to convert plants to other fuels or shut them completely, strangling the flow of avgas to other countries.
The USA's largest manufacturer of the tetraethyl lead additive TEL-B, which helps avgas maintain its 100 octane rating, has indicated to the FAA that it intends to cease production, further encouraging the FAA to phase out leaded avgas.
According to the FAA, the only other practical source for TEL-B is China, which the FAA believes will cause supply problems in the future.
Viva Energy, which manufactures 100LL at its refinery in Geelong, Victoria, says it has no plans to stop producing the fuel.
"Viva Energy intends to continue manufacturing Avgas 100LL at the Geelong Refinery for the foreseeable future," a company spokesperson told Australian Flying. "Viva Energy does not currently import avgas 100LL as the scale of our manufacturing in Geelong is sufficient to supply the Australian market.
"The USA's phase out of 100LL will have zero impact on Avgas supply in Australia."
A spokesperson for the Department of Infrastructure, Transport, Regional Development, Communications, Sports and the Arts told Australian Flying that the government was taking a wait-and-see approach to 100LL.
"The department notes the Federal Aviation Administration’s announcement on leaded aviation gasoline," the spokesperson said, "and will continue to monitor changes in technology and approaches in overseas jurisdictions which may inform future Government policy in this area."
-Steve Hitchen