Clarification: Only piston aircraft require leaded fuel. Which is unfortunately a pretty big part of the general aviation market, but similarly sized turboprops do also exist (though are more expensive) and it doesn’t apply to modern commercial aviation at all.
Further clarification: Only gasoline powered aircraft without the Auto Fuel STC require leaded fuel.
Although, there is an initiative underway to fully phase out leaded avgas. G100UL is the FAA approved formulation. Exciting time and long overdue.
No, G100UL is still going through the FAA approval process. But it’s been approved for many specific engines already, but the majority still aren’t allowed to use it. For a full FAA approval we could be waiting another 6-9 years.
The Next big problem is availability, which will only come with time. There are only a few airfields around that stock the fuel. (And from what I can tell… none that are here in Australia)
“FAA approved STCs for the use of G100UL in all general aviation piston airplanes in September 2022”
https://www.avweb.com/ownership/fuel-news/gami-begins-g100ul-stc-sales/
Except republicans are seriously trying to require that all airports that receive federal funding to still offer leaded gas. For reasons.
