[kube-system]

With as conservative as aviation is, and as long as airplanes last, I doubt anything about it will be quick. I’m amazed it has taken this long to get a single approved 100LL replacement, considering high octane unleaded fuels have existed for decades.

[jabl]

> With as conservative as aviation is, and as long as airplanes last, I doubt anything about it will be quick.

You may well be right.

> I’m amazed it has taken this long to get a single approved 100LL replacement, considering high octane unleaded fuels have existed for decades.

Outside of some specialized racing fuels, no. And nothing fulfilling the other requirements (distillation curve, vapour pressure, etc etc) of 100 octane aviation gasoline (this is measured with the MON procedure, as opposed to RON or AKI you'll find at your local gas station) at somewhat reasonable cost has previously been introduced.

I think the reasons why it has taken so long are 1) it's a genuinely hard problem 2) it's not a very large market.

[kube-system]

I’m aware that it’s MON (there are race fuels above 100 MON) and that there are different requirements for operating at altitude. Obviously it’s a specific application with specific requirements.

I think the problem would have been solved a lot sooner if there was any urgency to switch, either by the people buying it, or by regulators.

The switch with automotive fuels was easy. Cars are disposable by comparison and regulators banned lead-burning ones out of existence.