I wonder if there have been any studies of lead toxicity around gun ranges - which have large air extract systems to protect the users from lead dust from bullet impacts?
I wonder how many gun ranges are situated near airports?
We don’t need unleaded avgas on any real, genuine health grounds. The lead measurable in the atmosphere is as is correctly put, so small as to be a non-issue even near the most heavily used airports. Globally most GA airports have so few movements that the lead levels would be below detection limits of any of the available test methods. I’ve been in the aviation fuels and GA aircraft commercial operation and ownership circus for around 40 years professionally and am qualified (highly) as a chemist in the aviation fuels and lubricants business, a commercial pilot with a hell of a lot of experience, and have an enormous number of air-cooled engine overhauls under my belt. There are currently NO AVAILABLE UNLEADED FUELS GLOBALLY that I’d even consider running at all in any aircraft engine I have owned. They are just NOT necessary, and are in fact harmful to some in certain operational circumstances in certain engine types/installations combinations. There are IMO, a hell of a lot of people globally with a hell of a lot of self-congratulation going on, but who are still so far from properly understanding the FULL impact of all of the current offerings on a significant proportion of the fleet, that it’s extremely important that programs like the ‘wound-up’ PAFI and the new EAGLE program are allowed to INDEPENDENTLY cover all of the issues without any personal interests involved. I could go on for many hours about some really serious operational issues of using any of the existing (and defunct) unleaded avgas offerings, but that’s not going to happen in any public forum… The delays have been IMO absolutely justified and should continue until all of the relevant issues have been PROPERLY and throughly discussed and addressed. Enjoy the process everybody, and ignore the noise being created by a lot of people in industry and government and dare I say ‘fools in various interest groups’ who are stirring up hysteria about us all being biologically affected by tiny lead pollution after the worlds population sat in traffic for decades breathing lead filled fumes every day of their life, yet still had the brains to go to the moon, make iphones and PC’s and actually live long healthy lives… it’s such a joke that people think the tiny bit of lead left in the atmosphere is a problem to anybody, whilst ignoring the real issued with the alternative fuels…
Show me the long term study directly pointing at leaded aviation fuel as the source of children harmed by inhaling byproducts from leaded aviation fuel. We have multiple decades of leaded fuels in use on highways and skyways so, assuming there is direct evidence, it should be easy to demonstrate cause-and-effect, not anecdotal correlations.
Show me the proof that removing leaded fuels in an environment reduced the “harm” said to be caused by leaded fuels, not just in the aircraft engine but, in the human population, as well. We know a few studies have been done to attempt to force unleaded fuels down GA’s throat (and a few jurisdictions passed ordinances with the same goal) but, where is the evidence this will do anything besides stoke someone’s equity numbers to their peers/community?
Would it be nice to remove lead from fuels? Sure. But, the cost is prohibitive for the GA fleet to convert the old engines over. Someone is going to make a lot of money doing this - and it’s not the GA fleet owners.
Likewise, passing ordinances to prohibit leaded fuels with no substitutes is a fantastic way to shut down some prime real estate and redevelop it as fantasticly expensive homes/communities. After all, the airport was there first but, the wealthy neighbors - who’ve been trying to get it shut down for years/decades - just found a new “hammer” with which to achieve their goals (all while looking wonderfully ESG to their peers).
If you want to see a transfer of wealth, just follow the laws portrayed as “saving the planet”. They rarely save the planet but, they do destroy jobs, careers, lives. Understand why the folks demanding the elimination of a product with nothing but anecdotal evidence push so hard. Once you find the source of their agenda, you’ll begin to understand why they’re so adamant. And it won’t be the reason they’ve been so vocal about.
Collectively educating liberal democrats in blue states, would be like teaching a bowling ball how to swim. They don’t care, and won’t listen to reason. They would shut down all GA airports if they could.
What about non-liberal and conservative leaning Democrats. Do you think that would also be the same?
So many of you are saying that GA should get a free pass on this while others had to deal with it, and did so.
If GA gets a “hall pass” why shouldn’t other groups get one too.
Maybe we could find a viable solution. Something like, no new GA aircraft built from this day forward will be powered by an engine that requires leaded fuel. And all overhauls of engines that require leaded fuel will either not be allowed or will be a conversion to use unleaded fuel.
@Robert B. You beat me to the “viable solution” part
Great article, Paul.
There is no question that lead is bad for people arguing about levels is nonsensical.
Just because something has been done for a long time does not make it smart or right.
We have learned that a lot of things that used to be done were bad for us; we stopped doing them and are better for it.
People “Believe” lead is OK; “Believe” is not fact or reality; we know better.
As for lead in engines; In Canada, my friends from refineries have confirmed that 80/87 never had lead in it here; lead was allowed if needed to achieve octane levels, but was never needed.
It is likely that 80.87 in the US was also lead free; the lead was not needed.
When 100LL was introduced, we started having problems with engines that never had problems before.
Valves and sludging of oil passages, particularly in small Continentals or old low compression engines of any kind.
A mechannic friend just showed me pictures of an engine which failed due to lead clogged oil passages in the crankshaft; an expensive forced landing.
An engine that was approved and should have been operated on unleaded fuel; Mogas.
Lead is not good for valves; all aircraft have hardened valve seats; so any issues of valve recession, simply don’t happen in aircraft engines.
Cylinders on approved engines go much longer without problems on Mogas; at least 50 percent more life; that is fact.
Unleaded fuel is better for engines.
Taking forever to introduce unleaded fuel is nonsensical.
Unleaded 100 has been in use in Scandanavia for years; engines and people are doing fine.
Lead for fuel is only produced by one company; the only ship that transports it is very old; it could go out of service at any time and would not be replaced, because lead contaminates whatever it is transported in.
The supply of lead for fuel could be gone at any time; get in front of the problem!
Stop fighting the inevitable; get things moving; we will all be better off.
Hjelmco Oil in Sweden introduced unleaded AVGAS as per standard D910 already year 1981. Our second generation unleaded AVGAS Hjelmco 91/96UL was introduced year 1991 and approved the same year by the Swedish Civil Aviation Authority. Lycoming approved the fuel already year 1995 in their SI 1070. The 91/96 UL AVGAS met the D910 standard for grade 91/98 leaded AVGAS. The 91/96UL AVGAS is the standard AVGAS in Sweden and we have millions of flight hours on thousands of aircraft and under actually any weather conditions for 3+ decades. So sure there are data. The reason for it is so much used is also that is about one dollar cheaper per US gallon than the 100 LL.
There is a reason why the US have their problems and that is that Flight Magazines etc have avoided to tell the market that there were solutions outside the US. For example the AOPA Pilot has never written anything about the Swedish unleaded fuels except for a two inch long article when our unleaded AVGAS 91/96UL was tested and observed by AOPA staff at GAMI on a Piper Navajo Lycoming TIO540 engine with everything in the red and still not knocking. (with the help of GAMI Prism system). So journalists are also responsible for the US situation.
As I have developed both the first, second and third generation of unleaded AVGAS I have made several attempts to gain acceptance in the US. Town hall meetings have been made in California 11 years ago!!. I refer to flying Magazine https://www.flyingmag.com/blogs-flying-time-transition-unleaded-fuel/. You will the Power Point presentations if you Google.
So what about the future? Exotic new fuels will be expensive - you will have to pay for the octane numbers. Just compare the difference in price for high and low octane car gasoline at the pump and then extrapolate to gain another 10 octane numbers with exponential increase. (octane numbers get exponentially more expensive the higher you go) There will be I predict changes to the engines to operate on mid octane unleaded AVGAS. That should be the most cost effective solution for the GA and will be on a path with no technical surprises.
I just read Paul’s article, the Politico article, and the 2023 article “Leaded aviation gasoline exposure risk and child blood lead levels” (by Zahran, Keyes, and Lanphear) published in the Proceedings of the National Academy of Sciences Nexus (a peer-reviewed scientific journal published by the US National Academy of Sciences, one of the most respected scientific agencies in the world).
The Zahran et al. article makes a compelling scientific case for an association between blood lead levels among young children and (i) airport proximity, (ii) prevailing wind direction, (iii) volume of piston-powered air traffic, and (iv) sales of 100LL (all at Reid-Hillview Airport in Santa Clara County, California). I see no way to examine the results and not conclude that 100LL was a meaningful contributor to blood lead levels among the children in the study.
Making matters worse is the fact (which has been known for a very long time) that lead is bad for humans with the greatest adverse effect on the neurological development of young children. Arguing about a possible “safe” level of lead among children isn’t useful because determining such a level is probably not feasible. Given current knowledge, experts worldwide strongly recommend efforts to reduce lead in the blood of children to levels undetectable with standard clinical tests. The epidemiological and toxicological basis for this recommendation is very well established in a large, credible, peer-reviewed scientific literature.
If 100LL is the single largest source of lead emissions into the environment in the US at the current time (as noted by multiple credible sources) then general aviation has problem and it isn’t going to go away until the lead is removed from avgas.
Imagine two water fountains next to each other. Above one is a sign that says “the water in this fountain contains measurable amounts of arsenic but at levels not proven to poison you” and above the other is a sign that says “the water in this fountain is just like the water in the other fountain but has no measurable arsenic in it.” Which fountain do you think the general public would want to drink from? Which one would you drink from?
BTW, I fly and maintain an experimental homebuilt airplane, I own, maintain, and drive/ride an antique car and an antique motorcycle, and I have fired tens of thousands of rounds of ammunition in indoor and outdoor firing ranges. I am not interested in limiting anybody’s fun or livelihood. I am interested in facts, and the facts about the effects of lead on human health are pretty clear and seriously unfavorable.
I already told our airport commission that as soon as 100UL is available anywhere within 50nm, I will be going there for fuel, so if they want my business, they should try to be an early adopter. I want the improvements to my engine longevity. Regarding the environmental and health impact, I don’t think it’s worth arguing over. It’s a negative pollutant, not a positive, so we should do what we can to get rid of it. We should in all cases, try to have as minimal negative affect on the earth as is practical. Personally I’m sick of having all my food contaminated with glyphosate and phthalates, and would love to see them gone as well.
The biggest problem I see, with moving the fleet to 100UL, is that we’re gonna need someone to develop a cologne that smells like 100LL being burned. For some reason I just love that smell, and I’ll miss it when its gone. 
I use Santa Monica airport and I’m not happy.
As a community, we have had our heads in the sand about lead - and for decades we have had our heads in the sand about noise.
I suspect most airport neighbors’ opposition isn’t really motivated by lead: it’s motivated by noise. And for fifty years and counting we’ve said “we shouldn’t have to be quiet - we were here first” and we were being stupid. It’s possible to be quieter: listen the next time a Rotax-powered training airplane takes off and compare that to a C152. Higher RPM, 3-bladed prop, effective muffler, world of difference. Then listen when some numbknuckle does a full throttle departure in a large-engined piston with the prop all the way forward and the tips going at M1.05, when it’s been shown that a lower RPM - with dramatically less noise - would give better takeoff performance. It’s as if we were actively trying to make enemies.
Yes, we were there first. So were the cars. Know what? The cars got quieter: we didn’t.
And the same goes for lead. Those noisy C152s were originally designed - 50 years ago, or more - for unleaded fuel. They’re still getting lead fouling from the garbage we have in our airport fuel tanks. It’s not like there’s any mystery about how to make engines run on UL94: drop the compression and accept that you get less hp per cubic inch. And if that’s too heavy, join the 20th century (it’s quarter way through the 21st), put a gearbox on it and increase the RPM - yes, it’s entirely feasible and the fears about gearboxes are unjustified, resulting mostly from the efforts of amateurs trying to put gearboxes on automotive engines for Experimentals. Geared engines are quieter, too. But, for 50 years, we refused to adopt any new engines (except the Rotaxes - and then painfully slowly). And we have refused to tell the operators of planes with antique engines that it’s time to derate and run on 94UL.
Soon we will have no more urban airports, and we’ll be able to sit in our recliners with photos of our old lyco powered chariots on the wall and grumble that we were there first.
I’ll volunteer for that study, started my logbook at 9 years old, worked side by side with dad on our family airplanes, flown my whole life, ready to retire from the airline and flying piston airplanes more and more… I’m probably a good candidate to check against a city kid with no drivers license to compare the lead differential.
As a child raised in Los Angeles with parking lots for freeways and cars running on leaded fuel without converters, I cant see how a few planes a day is contaminating kids??? I know that a lot of planes that can are running on auto fuel to save money. I’m sure that is the same at most all airports where people have the ability to purchase non-alcohol fuel (not Arizona).
Question is how did my generation survive? There should NOT be any baby boomers if this is where the lead in the children is coming from.
The talk about lead harming the engine is not addressing the problem that was caused when it was decided that they would only produce one fuel for aviation. Anyone remember RED, BLUE, GREEN, and PURPLE fuel??? 100LL was a compromise fuel that was added to the mix.It contains more lead than the old 100 Octane but less than the 115. Yes low compression engines don’t like it or need it. But high compression engines NEED it. Go to the Reno race and see what they are using, its not 100LL (VP racing fuel LEADED) say goodby to motorsport racing if you cant have leaded 130 octane.
I have done some research on the cause of death in the United States in 2020 and found some big numbers. Hiway deaths at 32,719 and 2.3 million injured. Work place deaths 3929. Heart attack and cardiac 600,213 . Tobacco related 159,260. Other cancer related 585,202 and drowning & injury at 785 with 79% of these victims under 5 years old . No where was any mention of death and injury from avgas which only comprises 0.19% of the total gasoline sold in the US… Looks like Avgas is not much of a threat to mankind so issue cooked up about it being a dangerous commodity is really a non issue. George Gould @ KGLS
How far back in the archives did you have to search to find a photo of a plane being refueled with 100LL for only $2.49 a gallon?
“Reliability of automotive engines today is definitely ‘aircraft quality’.”
The statistics of the experimental segment does not bear out the statement that automotive engines are “aircraft quality”. The engine failure rate is significantly higher with automotive conversions than with traditional aircraft engines.
We are not alone. The Marxist inspired hate of other people’s interests is EVERYWHERE. (This has nothing to do with communism and everything to do with the overall collection of ancient dirt Marx threw together in his writings).
Wouldn’t it be nice next time someone on stage or online made a snarky comment about how “No one needs a _____”, if the reaction from every pilot, fisherman, hunter, musician, motor cyclist, snow boarder, golfer, oenophile, car lover, SUV owner, camper, surfer, etc. was to object and leave?
I think it would. And I think it would lead to some seriously good changes.