As a private pilot: The same. I always took extra care to cut back on the engine after takeoff, crossing the homes near the airport more slowly and without ascending much. And I avoided pristine landscapes or at least also slowed down a lot for a much quieter engine and prop. Because when I was at home or in some national park I hated those noisy small planes as much as the next guy.

With a propeller the engine is not alone in producing noise, the propeller can easily be worse. Especially when you are perpendicular underneath an airplane crossing above.

Still, what I find even worse is that general aviation still uses leaded fuel. I know this is so "esoteric" for most people that few really care, because it is so abstract. As someone who went through a heavy metal diagnosis and chelator treatment (university clinic, lab proven exposure) I know that even the tiniest amounts still have an impact. Not a clinical impact, you are not sick. But your brain and everything works a bit worse. With tiny amounts adding up over decades any small problems you get will be attributed to "age", "stress", "it's in your head". Because while we know, statistically, that there is an impact (that is why the _medical_, threshold for lead, and others, is zero), we are unable to make any useful statements for individuals. Which means for any given person the problem does not exist, and for the population level it remains an abstract threat.

So noise is one thing, but spreading lead over the landscape - yes in tiny amounts, but I believe it still adds up and matters - to me is even more outrageous.

I apologize, for years I spread lead over some, or many?, of you guys here when I flew around the Bay Area. At the time I completely ignored the "LL" on my avgas. Only after my own clinical encounter did I realize what it meant, suddenly it was more than just a technical term.

https://www.faa.gov/about/initiatives/avgas/

Student pilot in the Bay Area here.

I completely agree. My CFI has spent time making sure I understand how to reduce noise impacts of my flying. I live out in the hills which means planes and motorcycles are the only noise intrusions I get on a consistent basis. I wish I could do more for the noise issue as a pilot.

As for the lead issue, I had a small crush on an experimental that is being developed. The company is using a brand-new engine that can technically burn mogas (Motor Vehicle Gas) but the wings are constructed such that putting any ethanol in the tank is a severe safety issue. This combined with the fact that 100LL and Jet Fuel (diesel) are usually the only two fuels available, it seems like a lock-in for more lead consumption.

While there is some good news in the lead/noise department, it's not taking hold as much as I think it aught to: there are electric trainer aircraft produced now that provide very low operating costs, much less noise and release no lead. Unfortunately, I was reading that the performance characteristics make them a less desirable training aircraft than a Cessna 172 so adoption is slow.

Question for parent: I know the FAA's avgas initiative has been around for a while, do you know of any significant progress they have made in the area?

Is the use of leaded gas just because most small planes are old? Do new planes still require leaded gas? It seems absurd that avaiation gas is still leaded when it was phases out decades ago everywhere else.

It's the last hold-out of leaded gasoline in the US that I'm aware of and the landscape is complex to say the least. Some aircraft engines still require 100LL to perform within spec but most modern engine designs can also accept high octane "mogas" or motor-vehicle gas. mogas is also often not available inside an airport so getting it requires a vehicle and gas-cans.

Fun fact: most small GA aircraft still use the exact same engine technology that they were developed with despite needing to occasionally replace the engine. Automobile engines have seen a lot of advances in the last 60 years but any given Cessna 172 you see in the sky is likely still working in exactly the same way as in the 1960's.