I seriously doubt there’s a measurable amount of lead in the air from 100LL without sticking a probe in a muffler.
Regardless of the actual environmental cost, it looks bad when there’s a school under the flight path and the kids test for elevated lead levels. It doesn’t matter if it’s negligible or not.
Pilots around here seem to be roughly divided into two camps. The first is dismissive of the problem. The second says that one way or another, lead will be used as a cudgel against GA. So they should get behind the issue and push for a proper replacement as soon as possible.
People in the first camp will lose in the long run. The second set has a chance.
You can read the study here:
Significant? I’m not qualified to say. But it was measurable.
Court cases aren’t based on “looks bad”. If it was challenged it would fail.
The county can do whatever it wants (and did). Even if it could be challenged, it’ll take years to fight. And it still looks bad. No one wants to be on the side of saying that elevated lead levels in kids is fine and dandy.
I call shenanigans on any physical data collected. It’s literally a minuscule fraction of a fraction of a fraction of what was put in the air by cars and commercial planes when lead was prevalent.
It doesn’t pass the smell test and it wouldn’t be the first time a group used data under the guise of science to bamboozle a court case.
And? That was a bad, bad time. Leaded gas lowered IQ by about 6 points on average, and may have doubled violent criminal behavior. Telling parents that it’s ok, their kids are only losing half an IQ point, is not a winning strategy.
Now that you mention it, my first instructor trained me to smell the fuel samples we drained from the airplane during preflight to verify it was fuel, not water (along with checking the color). So here’s what occurs to me… Never mind the kids under the flight path, how many pilots have been harmed by getting a snoot full of lead every time we flew or fueled an airplane?
I had avgas on my hands all the time. And besides sniffing fuel samples, I spent a lot of time leaning over wings while pumping fuel which was great for absorbing fumes. I wonder how many IQ points I donated to my various pilot licenses.
You probably aren’t getting much when sniffing. Tetraethyl lead has a low vapor pressure–less than kerosene. Avgas has an overall vapor pressure of ~300 mmHg, while TEL is 0.2 mmHg. Mostly you’re just getting the most volatile hydrocarbons.
Skin contact might be a different story, though.
Great, now I need another rationalization for my idiocy. I’ve been using the leaded fuel excuse for years!
I don’t want to veer off on the topic. I’m just casting doubt that they measured the lead from aircraft. The flights are few and far between and it’s low-lead. It’s not even regular leaded gasoline. The likelihood that they have actual measurements of lead in the air from planes seems unlikely.
100LL is not actually low lead. It has as much lead as the most leaded automotive gas had during its peak. It’s just low compared to previous avgas formulations.
I agree that with so few GA aircraft in the air, lead isn’t a problem. But ISTR hearing decades ago that 100LL has more lead in it than regular leaded mogas. Dim memory.
Here’s the historical lead content in automotive gas:
You can see it peak at 2.2 g/gal, which is 0.58 g/liter.
100LL contains 0.56 g/liter of lead:
https://www.exxonmobil.com/en/aviation/products-and-services/products/avgas-100ll
Ignorance fought. I certainly cleaned enough of it out of aircraft spark plugs. A royal PITA.
Well, it’s low compared to standard avgas 100, which was 1.12 g/liter 
.
The effort against 100LL is not just tailpipe emissions.
Everything in the supply chain from mining the lead to making the tetraethyl lead fuel additive to refining & blending the fuel to storing it to transporting it to dispensing it to finally burning it releases lead into the environment. Every step of the way lead is escaping into public.
100LL in 2023 may not be much total lead compared to the 1960s-era car consumption, but by current standards it’s a hefty chunk of the USA’s total lead emissions. And segregating it from the rest of the fuel supply all down that supply chain causes lots of problems and therefore costs that everyone wants to avoid.
ISTM we’ve now got the chemical engineering skillz to create a drop-in fuel at a semi-affordable price. So now the long pole in the tent is legal.
IMO It will take something like the 1994
to provide enough of a liability shield to the suppliers for this stuff to go forward. No supplier can afford a world where every GA crash results in them being sued over their “franken-fuel.”
SAF for jets is struggling through a similar “valley of death” right now, where obstacles to scale ensure the price remains uneconomic, while regulatory / civil liability / environmental uncertainty is greatly slowing progress across the valley.
No. More important is that a selection is made of one of the 4 possible fuels, rather than “leaving it to the market”. When you leave it to the market no one decides to do anything as they don’t want to make a mistake investing substantial amounts of money supporting a fuel which rapidly disappears from the market.
Oshkosh. A T6-Texan went into Lake Winnebago with 2 onboard early today. No updates on recovery. Also some type of rotorcraft incident in the ultralight area. Unknown if it was a mid-air collision.
Oshkosh update. NTSB reports the collision was between a Rotorway 162F aircraft and an ELA Eclipse 10 aircraft.
Also, one dead, another injured as small plane crashes into Lake Michigan