You say that in the past tense... But pretty much every propeller plane worldwide still uses the stuff...

Only in piston engines, which are a minority of propeller planes. Most commercial propeller aircraft are turboprops, and they use jet fuel. And diesel engines are slowly taking over from gasoline in piston engines.

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mh- 2 hours ago | parent [-]

Correct. For others reading this though: virtually all piston-engine GA aircraft in the US today are still burning 100LL (leaded), and there are nearly 200,000 of them actively flying.

There is a timeline to transition to UL, but very low collective confidence it'll happen by the 2030 goal.

edit: to the commenter that fired off the reactionary reply and deleted it before I could help you. No, not because "[rich people] won't do the right thing." It's because lead is an anti-knock additive for piston engines, and a safe replacement has to go through unimaginable amounts of testing. Once it's certified, one must still figure out scaling production, distribution, etc. Aviation is a very slow moving industry and regulatory environment, which I'm personally thankful for.

PDF (77pgs): https://download.aopa.org/advocacy/2026/2026-01_Draft-Unlead...

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2 hours ago | parent | next [-]

[deleted]

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ck2 2 hours ago | parent | prev [-]

the amount of lead that is acceptable is ZERO

ZERO, thirty years ago when there was definitive proof is it forever and irreversible

all lead exhaust aircraft should have been phased out a decade ago if not two decades ago if they cannot be converted

again, there is no acceptable amount, imagine it being sprayed on you, your car, everywhere

your body tries to process it like calcium and stores it forever

how much damage and disease to you and your family are you willing to accept just so someone can keep using their prop aircraft for another decade to make profit?

yes it's all about the money, it's pretty obvious, if there wasn't profit involved it would have been phased out with cars THIRTY YEARS ago

all that lead sprayed all around the land and on people is FOREVER, it doesn't go away, it doesn't wash away, it doesn't evaporate

	▲	mh- 2 hours ago \| parent \| next [-]
		I'm unclear who you're arguing with. I don't fly GA and I live under the approach to a GA airport, which is why I'm well-read on this subject.
	▲	cucumber3732842 15 minutes ago \| parent \| prev \| next [-]
		It's mind boggling that people will screech about how the professionals say zero but then turn around and act like GA is a big deal, despite the fact that the same professionals will say that unless you have occupational exposure other vectors are going to be what dominate your lead level. And by "mind boggling" I just mean a more polite way to say "condemnation of people's logic and reasoning abilities or honesty" Yeah, sure we should get rid of GA leaded gas and we're working on it but it's not really a front burner priority because of how little it gets into people.
	▲	dalyons an hour ago \| parent \| prev [-]
		personally i think we should just stop selling the leaded version, tomorrow. alternatives exist, update your planes or dont fly, but no more leaded fuel.