Finding that lead emissions from aircraft engines contribute to air pollution
federalregister.gov
federalregister.gov
I enjoy AVWeb on YT for AV news (really, I just enjoy the humor/personality of Paul Bertorelli lol), here are a few insightful videos that summarize the story:
The Long, Twisted And Slightly Ridiculous Story of Avgas Part 1 (14:22) https://www.youtube.com/watch?v=9F-WngVMJBQ
Part 2 (15:15) https://www.youtube.com/watch?v=Mvse4Xhzwuk
and
G100UL Approved Now What? (When the FAA approved the first unleaded 100-octane avgas a year ago) https://www.youtube.com/watch?v=ibIkuyBL9i8
It's not odd, it's exactly what you'd expect. The only odd thing is that it took this long.
Many (older) aircraft engines need leaded fuel.
You still have to apply for and buy an STC for your specific airframe's serial number and engine's serial number. Then you have to add some paperwork to the logbook and POH and add placards to the fuel fillers and cockpit.
In theory you should be able to automatically get it for anything which was approved from the factory to use 100LL, but the STC application form (here: https://stc.g100ul.com/aircraft/) does not allow you to select most mid-century large radials (which were usually originally certified on 130) or the airplanes they were installed on.
To be clear, this is a great thing, but you can't legally just fill G100UL in any random airplane.
I don't think it needs to work in every conceivable 100LL aircraft: just almost all. Every is a high bar.
Airports don’t always have the space for a second avgas tank (if this is the in between option), and if they did don’t necessarily want to spend money on setting up that infrastructure. So the current catch-all is to provide leaded which is cheaper and guaranteed to work in everything.
I think it’s great we are getting this forced through - it will make the approval process streamlined (like loda was) and removes a major reason people used to push airport shutdowns.
Lots of airports are owned or regulated by local governments which might want to move that single tank to just unleaded. E.g. Santa Clara County banned 100LL at local airports.
Forklift upgrades suck, too. You're best off getting some of the way along and then forklift. Arguably we're reaching that point.
The TC says you must run 100LL. The STC says you can freely mix G100UL in any ratio. The legal/certification problem is solved.
Like small planes are spewing lead over everywhere they’re flying. I’m glad this is happening.
I don’t really care about small operators vs the health of everyone else, and especially kids in the case of lead.
Operating a plane is a privilege, not a right.
Oh, we aren't talking about tire dust? Never mind.
Unlike lead, we've only recently had the technology to measure and quantify tire wear pollution. For example, we didn't realize until 2020 that 6PPD - already toxic to many aquatic organisms - can oxidize become 6PPD-quinone, which is acutely toxic to coho salmon and some other fish species. This solved a 20 year old mystery of so many coho salmon died after a rain storm.
That's why the California Environmental Protection Agency has passed a rule requiring tire makers to declare an alternative by 2024. https://dtsc.ca.gov/scp/motor_vehicle_tires_containing_6ppd/
That's in addition to the particulate pollution from tire wear. ("Research from Emissions Analytics shows that particulate mass emissions from tire wear is thousands of times greater than those from tailpipes, which have been vastly reduced in recent years by high-efficiency exhaust filters." - https://edition.cnn.com/2022/08/16/world/tyre-collective-mic... ).
We of course need to regulate them better because electric cars are heavier, so tire particulate pollution is expected to increase over the next few years.
There's also brake pad pollution, like the EPA's Copper-Free Brake Initiative to remove copper, "mercury, lead, cadmium, asbestiform fibers, and chromium-six salts in motor vehicle brake pads." https://www.epa.gov/npdes/copper-free-brake-initiative . That's a voluntary program, but California and Washington have mandatory requirements.
I trust that you support these efforts to reduce car pollution, and are not simply using the lack of discussion about them in this thread in order to score internet points for implied hypocrisy?
Both tires and brakes have the advantage that they are replaced every few years/decade, so regulations can target manufacturers. An aircraft engine can have decades of life, so any costs of switching away from leaded fuel are felt directly by the owner.
They’ve also been known as a class as a problem (along with catalytic converter particles) for well over 30 years.
There have been multiple studies linking proximity to freeways with asthma and decreased life span, serious health issues like COPD, and even significant increases in sudden unexplained deaths.
45 million Americans live within the high risk zones (300 feet or meters, I forget), countless new daycares, old folks homes, and residential high rises get built there every day, and almost every American is exposed significantly due to being in vehicles on average of an hour a day with insufficient filtering.
[https://www.epa.gov/sites/default/files/2015-11/documents/42...]
The issue here isn’t that aircraft engines last ‘decades’.
It’s that aircraft owners are only legally allowed to use fuels approved by the FAA for their aircraft, and per the various authorizations for their aircraft. Which vary. The engines may get rebuilt, but without a very expensive type change and approval (often from the manufacturer) they’re the same design as the original. Which has the same limitations.
So until there is a viable authorized replacement (per the FAA), literally they can’t use it except in emergencies. Which only just became available. And they can’t change engines either. And they can’t just YOLO it legally.
Because fuel is a major cause of crashes that kill people already (usually contamination, or wrong fuel causing engine failures/flameouts).
And despite the FAA knowing of the risks of lead (or more precisely, knowing the various factors), they only recently did authorize a replacement.
So it’s as if that study on those plastics happened 30 years ago, and we’re just now getting around to it. Which essentially is what has happened with cars and the various pollution.
So raking anyone over the coals when a far larger, more damaging, and widespread crisis has always been going on for even longer and gets ignored? Yeah I’m pointing out the hypocrisy.
It’s always about resources in proportion to risk, and arguably the FAA has dumped far more resources and mitigated a far less damaging risk (in many concrete ways) far faster with this leaded fuel issue than one near and dear all of us.
Which also drives the call to reduce car use, wherein someone is also likely to point out that driving is not a right but a privilege.
> So it’s as if that study on those plastics happened 30 years ago, and we’re just now getting around to it. Which essentially is what has happened with cars and the various pollution.
Yes. And lead wasn't banned for interior paint until decades after some other countries. The US regulatory system is strongly weighted in favor of business over health and environment.
> raking anyone over the coals
As if! This is finding. The EPA must then "propose and promulgate emission standards", which the FAA must then turn into regulations.
It sets no deadlines, it makes no policy changes other than for the EPA and FAA.
I suspect it will take years before the first regulations appear, and with years to allow a changeover.
>Will I have to modify my engine or aircraft to use G100UL avgas?
>Other than placards, no modifications are required. A small placard is attached to the engine and "stick-on" placards are applied to refueling ports. In addition, there is a short POH supplement added to the AFMS.
"Regulations are the only way to solve market externalities" is not the same statement as "All regulations solve market externalities".
The market can never solve market externalities, by definition.
The vast majority of regulations don't work. At least not if your definition of "work" is to actually solve market externalities. But they're great for job security for regulators and politicians.
> The market can never solve market externalities, by definition.
This is not correct. Markets can solve externalities, through market transactions that shift ownership so that the externalities are internalized. The main thing preventing this is government regulation that raises transaction costs so that the necessary adjustments cannot be made. This has been known at least since Ronald Coase published his famous theorem.
In other words, government regulators prevent markets from solving externalities, and then complain that markets can't solve externalities so government regulators have to step in.
It's true that there are cases where there are no market transactions that can internalize an externality. But in those cases, regulation can't solve them either; there are no solutions for such cases. Welcome to the real world.
While this is often true, that doesn't mean it's actually an improvement.
Anyone commercial already has to go in for 100hr inspections all the damn time. The STC is unlikely to cost much relative to that, nor to add much additional hassle.
Anyone private can deal with it, they own their own plane and knew it wasn’t going to be a cheap hobby going in.
G100UL will cost a bit more than 100LL but it seems likely this will change a bit as it becomes more widely used.
I guess it puts people operating midcentury radials that haven’t yet been certified for G100UL in a weird spot.
Same thing with running certain large piston airplane engines on 100. They blow up.
> There are several options that involve no lead, generally substituting with ethanol
Ethanol is corrosive to aluminum. Thankfully airplane designers have never used aluminum in airplanes...
I’ve actually never experienced the, “California gas sucks” issue that car people from the mid-west talk about, have never had an issue with it. ¯\_(ツ)_/¯
Not that it matters when everything made for "premium" is tuned for 91 from the factory anyway, not 93
1) Few refineries make it, so it's MUCH more expensive. But if you're living in California, it is easy to miss because EVERYTHING is much more expensive.
2) Mileage is generally poorer, due to the mandatory ethanol mixes. But some places also usually mix in ethanol, and the difference is usually in the 10-15% range. So unless you have a good A/B comparison going, it's also easy for it to blend in with all the stop and go driving, and terrible road conditions.
3) Mandatory Ethanol means generally very poor storage characteristics. Which considering how much driving happens in California (and how dry the climate is in the populated areas), most people won't notice.
So does it suck? Comparatively, definitely! Is it likely to be noticed unless you're very aware and have experience with other options? Nope.
In the case of my vehicle it results in low/rough idle and positive fuel tank pressure which otherwise do not occur either at lower elevation or with ethanol-free fuel at elevation.
No idea about 240z specifically, but at least things designed for sustained high performance (like aero engines) tend to use valve seats made from some wear and temperature resistant alloy like stellite or brightray.
The recently developed G100UL unleaded fuel requires a change to the type certificate of the airplane (by serial number) and engine(s) (by serial number) to be legal.
Until that supplemental type certificate existed, these airplanes did legally need leaded fuel.
> Once it's legal
exception above.
If you can run, 100LL, you can run G100UL. The main issue is with mogas (standard car gas) - many aviation engines can't run it.
Another aspect is that many piston airplane engines need high octane because they have relatively high compression ratios: WWII era engines need 130 octane to develop full horsepower (they can be operated at reduced manifold pressure on currently available 100 low-lead gas), and even many post-war civilian engines require 100 octane.
Still another aspect is that the FAA is relatively conservative and doesn't want to approve something that might lead to, for example, vapor lock or fuel freezing issues.
I mean, high octane and compression relative to other 1960s engines. The common engines in nearly any single prop cessna have about a 9:1 compression ratio, which was massive back when it was built, but laughably bad compared to anything manufactured after the advent of Fuel injection and better piston geometry.
Modern cars regularly have over 12-1 compression ratios on 87 octane.
1960s era carbs and top ends were just abysmal and did a terrible job of mixing the fuel and air charge and controlling the flame front, because we just didn't have the kinds of computer controls and fluid dynamic simulations we have now, to dynamically prevent knock.
Rotax engines are modern and can reach identical performance figures or better, with the same weight or lighter, simply by using modern techniques like fuel injection or a small turbocharger. They do this while running on 91 octane
In the mean time, rebuilds have to meet the existing design. Which has specific standards.
It's not like Cessnas themselves can't be wildly improved on in general!
As an old Boeing engineer friend of mine used to say 'when the weight of the paperwork exceeds the gross weight of the plane, it will fly.'.
2) Lack of solid quality control relative to aviation fuels (see #1)
3) Power to weight ratio matters a LOT in aviation, and aviation engines run at typically far higher elevations for at least part of their flight time. So aircraft engines generally push things harder, have higher compression, and can be damaged more easily with 'junk' or contaminants.
[0]: https://www.bloomberg.com/news/newsletters/2023-10-12/fake-p...
[1]: https://www.bloomberg.com/news/features/2023-10-11/fake-part...
I'll be doing it, as soon as our home base carries it for my 56 o200.
AVWeb did a couple videos on the subject here:
Except that they did approve a lead-free fuel for use in all those engines last year. Banning leaded fuel is the obvious next step.
More specifically, I believe they certified that a particular fuel as suitable for use in ALL engines that previously relied on leaded fuel. Until that happened there was a somewhat legit concern about banning leaded fuel. What people are afraid of now is a monopoly on the new fuel leading to higher prices. But there's already a near monopoly on leaded avgas.
It would be really cool if someone developed a new aircraft engine suitable for replacing all the old models and able to run on a wide range of fuels (this may actually exist). But even then its a slog to get that engine certified for all the planes you'd want to use it on.
As a recent article here talked about, nobody is making new aircraft for general aviation. Or at least, nobody is making anything innovative for it.
But there exist plenty of engines that are good enough for planes and can run on a wide range of fuels. They are just not getting into GA planes.
If you can afford private aviation, the price of the fuel is not going to be a big concern. It's already $7-10/gallon and that is a pretty small component in the all-in hourly costs of operating an aircraft.
I have never flown to an airport with it yet. i have probably landed in over a dozen different airports in the last few months with a leaded gas engined plane.
What is $250 in aviation terms? It's nothing.
Availability of fuel is a concern, sure. But a fire has to be lit on people's ass, otherwise they will not move.
> The FAA signed on September 1 supplemental type certificates that allow General Aviation Modifications Inc.’s 100-octane unleaded fuel (G100UL) to be used in every general aviation spark-ignition engine and every airframe powered by those engines.
All piston engines and aircraft are certified for G100UL.
There is now a legal alternative. Working as intended.
Edit, looks like there is an alternative https://news.ycombinator.com/item?id=38040091
It's already nearly choked to death by regulation, but that was a step too far.
But they also clearly have been working to mitigate it, and now that they have an alternate are banning leaded avgas and launching it.
So what is your rant about exactly?
Do you even see it in the list?
This NIH study shows it as ‘small, but significant’ - accounting for anywhere from 2.1-4.4% of the lead found in children’s blood near piston airports.
https://ehp.niehs.nih.gov/doi/10.1289/ehp.1003231
Less than 5% of the amount of lead total in their blood from that source, literally for the highest risk segment you can find. Even if completely eliminated, the other 95% isn’t going anywhere.
Even if you don’t average it out across the population, it’s hard to argue that isn’t so close to zero that nearly any significant benefit anywhere else would make it not a rush.
Most airborne lead pollution now is industrial anyway, and that is clearly the calculus there. As is the #1 and #2 sources of lead ingestion for children, old paint and old pipes.
I’m glad they’re getting rid of it, but I’m not going to complain they didn’t drop everything to rush it. Especially since if they did, they’d almost certainly kill more people in the resulting plane crashes.
If general aviation were to be banned, then as commercial pilots die off or retire, it would be difficult to hire new commercial pilots with as much experience as new commercial pilots have historically had.
* In the same category of human harm as nerve agents, dioxin, and methylmercury.
https://www.aopa.org/news-and-media/all-news/2021/july/27/ga...
https://www.epa.gov/archive/epa/aboutepa/epa-takes-final-ste...
Now they're going to ban leaded avgas, which should force the for adoption, since there IS now an approved general purpose alternative.
Now that there is an unleaded alternative, older planes will slowly replace their engines at the next engine rebuild. There is a grave pilot shortage already and the FAA loathes to make GA even more inaccessible than it already is so it’ll be a slow process.
An alternative exists, but the FAA needs to certify it for each aircraft type. The majority of aircraft types are not certified for this. No A&P is going to do this because the plane won't be legal to fly in most cases.
And at the risk of editorializing, I've never seen the FAA do anything with the goal to making GA more accessible, at least not intentionally.
They have. It's done. nobody needs to worry about liability for switching. Availability will be a short-term problem, and banning leaded fuel will get it fixed quickly.
What was your point point exactly?
It is fully compatible with existing engines https://www.g100ul.com/
>Will I have to modify my engine or aircraft to use G100UL avgas?
>Other than placards, no modifications are required. A small placard is attached to the engine and "stick-on" placards are applied to refueling ports. In addition, there is a short POH supplement added to the AFMS.
The engine change is shit pushed by the leaded-gas manufacturing lobby.
There's going to have to be a concerted effort to fix type certificates and fuel distribution all at the same time. A slow effort is going to be more problematic.
G100L is approved for all piston aircraft [1]. The only reason someone couldn't buy from them would be obstinacy.
[1] https://www.aopa.org/news-and-media/all-news/2022/september/...
[I am seriously curious; on the one hand, owning and flying a small plane is an expensive, privileged hobby which tends towards the lower-upper-class demographic, but it also requires complying with a shit-ton of government regulation and direction already.]
You still have to go here (https://stc.g100ul.com/aircraft/) and buy paperwork that makes your individual airframe and engine legal. What the FAA approved was for GAMI to sell that paperwork for all piston aircraft.
People just can't see the end result of their ideologies.
Lol, inaccessible? Y'all don't even need airstrips to take on and off, for Part 103 ultralights technically not even a license. Meanwhile, here in Germany, first pay up thousands of euros for the ultralight cert, and you have to use dedicated airstrips instead of your farm's field. Oh and if you want to get beyond ultralight, do everything from scratch for the PPL, no credit/transfers.
It'd be especially useful if they could run on regular jet fuel, then turboprops/jets and pistons could use the same fuel infra.
In the early days of aviation (like 1930's or such) there was some effort to introduce diesels for long-range aircraft, the idea being that the heavier powerplant would be offset by the lower required fuel load due to better fuel economy. But they weren't successful.
More recently there has been something of a renewed interest in aviation diesel engines, the motivation being they can run on Jet A-1 in addition to diesel fuel. Jet A-1 is what jet (and turboprop) aircraft use, and is available at basically every airport worldwide, is much cheaper than avgas, and no risk of being phased out like the leaded avgas being discussed in this article.
Diamond Aircraft have had success selling planes with diesel engines recently, and even started a subsidiary company to manufacture them: https://en.wikipedia.org/wiki/Austro_Engine
> It is a fuel additive, first being mixed with gasoline beginning in the 1920s as a patented octane rating booster that allowed engine compression to be raised substantially. This in turn increased vehicle performance and fuel economy.
But adding high-octane gas to a normal engine doesn't make it go any more boom, in fact, it goes less boom because it doesn't burn as much when it booms.
Modern engines can be designed to advance or retard timing based on knock, so they can run on different octanes and provide different power curves.
And that's exactly where i was wrong :-)
On many modern cars, high octane gas gives you more boom. They are designed for high octane gas, but the engine management computer is able to detect low octane gas and prevent damage from predetonation-- giving up some power.
>They are designed for high octane gas The vast majority of modern engines are designed for 87 octane, and not downrated to 87 octane, because that would give you poorer performance than a clean sheet 87 octane design, and single digit percentages matter here.
There's a whole lot of cars that say "Use premium fuel only" with compression ratios of >10.5:1, but rely upon anti-knock sensors to retard timing (and adjust mixture) to avoid detonation with 87 octane fuel.
I was a professional mechanic around that time, and I had coworkers that thought that not only would high-octane gas give more power, would also swear it increased fuel mileage. Neither is true. High-octane fuel has less energy per gallon than lower octane fuel, it can’t give better mileage. (Now, “mechanic” != “engineer”, but c’mon, guys.)
[0] Yes, Captain Pedantic, I’m aware of knock sensors and computerized ignition timing. It was a quarter century ago.
This stuff started to show up in the late 1970's-- the 1981 280ZX Turbo my dad had was equipped with a knock sensor and would retard timing and add fuel.
By the mid-90's this was relatively common.
More or less, if you want to build a light weight/high power engine you want a higher compression ratio. As the piston travels upward on the compression stroke higher pressures are achieved and this allows designers to take advantage of different crank/cylinder characteristics to make more power in a smaller, lighter package.
We used lead in car gas because engine timing technology and fuel delivery technology were analog/mechanical and really very limited in terms of tuning potential. The cheap hack was just to use a fuel that was more resistant to burning in the first place. Just add a hotter spark/ignition system and it was good to go design wise. Given the old tech running in most GA planes, this was a natural thing to do at the time and the problem was well understood. To point here, modern non-lead additives have been around for a long time and the problem can be adequately solved with a non-lead substitute.
If you wanna get deep with this, take your old normally aspirated car and bolt a turbo on it!
These things are possible without lead as well, it just costs more money to do so.
You can dump as much fuel in the cylinder as you want (in fact, most airplane operating handbooks call for a very rich mixture on takeoff because of the cooling effect).
"The Man Who Accidentally Killed The Most People In History"
People have been looking for alternatives for a long time, but it's difficult because leaded aviation gasoline is not a very large market, and there are substantial regulatory obstacles.
(In comparison, it was well-known at the time that ethanol can also increase octane, and it wasn't protected by patents.)
Lets look at numbers as of today:
Cesna 172 - 75kw engine, on 50kw power makes 1000km as 200km/hr. Engine plus fuel weight 350kg. The engine costs $26K.
Today's lithium batteries like ones used by Tesla is 280wh/kg. At retail similar batteries cost $400/kwh.
So, we can have 75kw electric engine and 100kwh battery at the same weight as ICE engine plus fuel on Cesna 172 and at a retail cost of $50K and have 2 hr flight of 400km. That isn't a worse starting point than what Tesla had 15 years ago against ICE cars.
If your fuel meets ASTM D 910, it contains lead. If it doesn't contain lead, it doesn't meet ASTM D 910 and therefore definitionally isn't 100LL, so if your engine type certificate data sheet calls for 100LL, it unavoidably calls for lead.
If you are flying an aircraft that is thus-certified, flying it with a different fuel is, per the FAA definition in 14CFR3.5, flying an unairworthy airplane.
"Airworthy means the aircraft conforms to its type design and is in a condition for safe operation."
That's the legal reasoning that the Gami STC is required: to change the TCDS of the engine and airframe to permit a fuel other than 100LL and still be considered airworthy. (The STC process is totally workable and, IMO, doesn't need to be "fixed" and Gami has basically done the work you're asking to be done AFAICT.)
That’s what the STC process does legally, just being done by the engine/airframe manufacturer instead of third party (presumably because they wanted to continue selling engines/airframes).
Don't forget that aviation engines are require a lot of regular rebuilds. In a car you wait until something breaks, in an airplane you replace parts long before they might fail to ensure it doesn't break when in the air. So for many we can just add replace the seats/valves in the next tear down and be okay.
Hospitals. Nuclear power plants. Airports. Laboratories.
Those regulations don't apply to 1. existing installations in trucks or 2. generators.
With engine failures in aircraft however, the consequences can be way more dire - particularly in GA where it's (at least in the US) even being allowed to fly without a license at all (Part 103 ultralights), and forget about regular legit simulator training on what to do in that case.
Take your total load (10MW) divide by 5 (2MW) and you need 5 2MW generators, buy 7 and run 6/7 and your "down for yearly maintenance" generator can be offline while your "oh shit we installed the wrong fuel filter and the injectors clogged" generator also fails.
Much harder in a plane.
If there is a conspiracy I suspect it's the government exerts a light hand on things rich people do.
What surprises me is the refineries didn't tell the light aviation industry they weren't going to make leaded gas anymore. If they'd done that the Feds would have kicked them some cash to develop an unleaded version.
You can just add lead to unleaded gas (which was legal until 1996 in the US), so even if you could convince them to be altruistic in this way others could just work around it.
Aero engines run at a substantial fraction of their rated power output basically full time[0].
The fact that auto engines can be run on unleaded, lower octane gas at 10,000' or more doesn't really tell us that the same low octane unleaded gas is suitable for an aero application.
[0] And in some cases are rated for more power for limited lengths of time such as takeoff. See here, for example https://medium.com/s/story/the-long-way-round-the-plane-that...
About 11 thousand barrels of 100ll are produced every day in the US. Compare that to 4.9 million barrels of diesel daily, and you can see why it is a bigger priority. In this case 100ll is a literal drop in the bucket.
But also its a rich guy hobby that generally isn't very visible.
> the FAA has a statutory mandate to prescribe standards for the composition or chemical or physical properties of an aircraft fuel or fuel additive to control or eliminate aircraft emissions which the EPA has found endanger public health or welfare under section 231(a) of the Clean Air Act. In issuing these final findings, the EPA is making such a finding for emissions of lead from engines in covered aircraft.
[1] https://www.aopa.org/news-and-media/all-news/2022/september/...
Clearly it isn't okay to harm someone without their knowledge or consent.
(yes in some other countries)
IMHO, it'd be much better to have an explicitly adversarial and separately-funded dual-track system at such agencies, similar to how the justice system works.
E.g. FAA-Innovation (responsible only for their goal) makes their strongest case and presents research on why unleaded gas should be adopted ASAP. FAA-Safety (responsible only for their goal) makes their strongest case on why no change should be made.
All arguments and facts are published in public. Then higher-level decision makers arbitrate and make a call.
The root of all evil is that from a career perspective, "defer and take no action" is always safer for individuals in positions of regulatory authority. Worst case, something that's always been wrong explodes, and you blame it on the last person.
In the current blended safety+innovation system, it's too easy to obfuscate intentional inaction in endless "more study is needed" bullshit.
Having written this, it almost seems like too obvious of an idea to even post about...
For example, before they figured out how to sell and onboard SMBs, there was at least three teams working on solving that problem while I was there, including mine.
Once there was a “winner”, that team would get more funding (aka budget) and the people on the other teams tended to be absorbed into the winning team or would be repurposed onto other projects.
This wasn’t a codified, explicit operating system, but basically is how they worked for awhile (but I’m unsure how it works now.) The gist was to hire smart people and let them figure it out.
The exemption for leaded fuel in GA should have expired a long time ago. It's ridiculous that the FAA was allowed to keep punting this issue essentially forever, and the only reason a transition is happening now is because they finally decided to take responsibility for it, rather than because there was any legal requirement for it.
GA flying is important for a lot of industry, and a lot of remote communities. it might have taken some work, but they could have found a way to use unleaded fuel in airplanes in fewer than 50 years.
Power tools run much better on it because it contains no ethanol.
My portable generator starts much more easily after sitting for a few months if I use AVGAS instead of what I buy at the pump. It's because the ethanol gums up the carbonator.
Are you telling me all these aircraft that fly over my house are filling the air with lead?
How much environmental lead contamination are we talking here?
Jets (and turbo-props) run on kerosene basically.
The lead is an additive that acts as a lubricant and older engines aren't certified to run without it.
> wherein it served as an effective antiknock agent and reduced exhaust valve and valve seat wear.
That's going to be bigger twins and prop planes like the Pilatus
I should've known intuitively that a turboprop isn't a jet engine because the thrust comes from the prop not the exhaust.
But this only affects avgas, which is high-octane gasoline for propeller-driven aircraft. Jet-A1, which is light diesel fuel or kerosene-like for jets doesn't contain lead.
This was true up until last year, when G100UL was approved as a drop-in replacement for 100LL. It does require a STC and the associated paperwork, but this is apparently pro forma and quite cheap, and doesn't require any modification to the aircraft apart from some placards. The problem, of course, is that G100UL isn't really available anywhere yet, while 100LL is still ubiquitous.
Until recently this was true. But since September 2022, G100UL is legal and certified for "every spark ignition piston engine and every airframe using a spark ignition piston engine in the FAA’s Type Certificate database.”
Not a rhetorical question, I am genuinely curious.
New designs must work with leaded fuel since that is the fuel which is available - until avgas contains no lead this will continue to be the case.
Side note, most new planes are sold without an ecu.
While I'm rambling, the dual spark in a GA engine is really interesting.
This is why the FAA wasn't in a huge hurry but at the same time they were WAY too slow. It should have been a crash priority honestly.
Increased lead in crops grown within a few miles of airports has been noticed.[1].
As had reduced IQ's in children living near airports. [2]
[1]: https://core.ac.uk/download/pdf/344932499.pdf
[2]: https://www.newscientist.com/article/2353962-children-living...
Imagine if 100 years from now, Brazil is an up and coming economic powerhouse, and economists figure out that they are doing so well because their strategists, businesspeople, scientists and engineers are all smarter because their food contains less lead than ours does. We'd quickly start outlawing high lead food, which in turn might make big swathes of our cropland unusable for food.
https://qz.com/africa/2053227/leaded-gasoline-is-now-banned-...
Luckily lead is very heavy and chemically active which makes it much easier to remove from soils than some of the nastier contaminants. You can essentially break it down with sulphur amendments to acidify the soil and then let the plants do the rest of the work. Eventually dilution does the rest of the work until it reaches background levels.
https://qz.com/2158594/do-you-live-near-enough-to-a-small-ai...
This could be an incredibly useful tool if it worked (and wasn't limited to just a few years worth of data).
but nothing works
Not much. Flying is a pretty niche hobby (and as others have pointed out, commercial jets don't use leaded fuel).
Wrong on all accounts. There are orders of magnitude less engine models used in air than cars. Profit margin for airplane companies are higher than cars (though volume is much lower). cars use the same model worldwide and pass certification all at once, planes sell in one country and customers are mostly responsible for 'acclimatization' or whatever they call it in your parts, but it usually is about lights color and placements or some nonsense.
the one thing that made planes be so slow, is that people who own planes have much more voice over legislation than people who own cars. Nothing else. That's why the whole industry used tax payer money to certify one special new gas type that will work on all existing engines (again, possible because much less variety, making it easier technically). You breathed lead for 60 years of legal lethargy just so a few people didn't have to spend a few pennies on their plane maintenance.
I thanks the FAA and other's countries flight authorities for the fact that I don't need to have an anxiety crisis every time a plane passes overhead.
Oh, and unlike with a car or truck, engine failure in a light plane, especially during takeoff, is VERY likely to result in death or serious injury.
Well, what are the safety implications of atomizing lead? This argument seems short-sighted.
There was a carve out because plane engines are expensive and old (the most common engine today is a 50 year old model). Presumably it was expected that carve out would just be temporary while we worked on finding an off ramp to unleaded avgas. Nobody wanted the FAA to just ignore the problem for decades.
It's notable, and is being banned for it. But when it's gone, it won't make any significant difference.
In this case, it has been a decades long process. But it's done now and the replacement fuel is available. Time to mandate the change.
That's why unleaded fuel came about.
Don't know about the US, but we had leaded petrol (gas) for cars much later here in the UK, ~2000 at least. I remember my mum's Austin Metro (which was from the early 90s/late 80s) ran on it, and we only replaced that car once I was in high school (and that was in 2001)
I was getting into it right as the ADS-B rules were coming into play. It is a cheap and easy (by aviation standards anyway) technology designed to prevent mid air collisions, and you’d have thought the FAA was requiring them to murder their children.
Who is exempt? Aviation. One plane makes noise over tens of thousands of people. The absolute worst are the stunt planes.
There have been great exceptions (Medical reform + BasicMED, small recent changes around experimental/amateur-built category, and the upcoming MOSAIC reform), but I think the old fogies have a point about the damage change tends to bring to this activity.
In neighborhoods or cities that happen to sit under take-off or approach paths for, or downwind of, very-busy airports that see a lot of prop plane traffic? Maybe a measurable amount.
Sure - some have eaten more, and others less. But everyone has been impacted. Half of the US population has blood lead levels above the CDC 'safe' level.
That's a bogus statistic. I went to look up what you could be talking about, and it appears to be pretty shoddy alarmism, not on your part but poorly or shadily written reports. (disclaimer/reassurance: Lead is bad for us, and heavy metal exposures are cumulative over a lifetime, so the lower the better, and we should keep lowering.) But what you quoted implies that we are not succeeding quickly enough, and from things I looked at, that is not a conclusion that can be drawn.
I didn't spend a lot of time on it, but just from a few headlines and an abstract, it's clear that the lead levels under consideration have been lowered recently (and for what I'm about to say, undoubtedly previously lowered other times), and are not toxicity levels but more like "hey, there's lead in this neighborhood". And the lead exposures they are talking about are "retroactively" encompassing the elderly who were exposed as children before the new levels (and unleaded gas) were a thing.
So, they're saying "Among the entire population, half of people have previously received during childhood lead exposures when we didn't have current standards that we would now consider to be, not even unsafe, but where geographically we should focus our attention looking at the sources."
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sources:
https://www.cdc.gov/nceh/lead/news/cdc-updates-blood-lead-re...
2021, CDC updated the blood lead reference value (BLRV) from 5.0 μg/dL to 3.5 μg/dL. A BLRV is intended to identify children with higher levels of lead in their blood compared with levels in most children... It is not a health-based standard or a toxicity threshold... should be used as a guide to 1) help determine whether medical or environmental follow-up are recommended and 2) prioritize communities with the most need for primary prevention of exposure. .. BLRV is a population-based measurement that now indicates that 2.5% of U.S. children aged 1–5 years have BLLs at or above 3.5 μg/dL.
https://pubmed.ncbi.nlm.nih.gov/35254913/
Considerable effort is expended to protect today's children from lead exposure, but there is little evidence on the harms past lead exposures continue to hold for yesterday's children, who are victims of what we term legacy lead exposures. We estimate that over 170 million Americans alive today were exposed to high-lead levels in early childhood, several million of whom were exposed to five-plus times the current reference level [which is not a health or toxicity level]. Our estimates allow future work to plan for the health needs of these Americans and to inform estimation of the true contributions of lead exposure to population health. We estimate population-level effects on IQ loss and find that lead is responsible for the loss of 824,097,690 IQ points as of 2015.
...and you can't add IQ points like that, most especially if you are part of the substantial segment of the population that says that IQ is a bogus measurement, a segment that heavily overlaps with environmentalism.
While the effects of lead compound over a lifetime, the measured figure is blood lead levels, which will drop to zero if you stop consuming lead, with a half life of 28 days.
Therefore, the measurements made in 2023 mostly reflect lead actually consumed by humans in 2023.
"...yesterday's children, who are victims of what we term legacy lead exposures. We estimate that over 170 million Americans alive today were exposed to high-lead levels in early childhood, several million of whom were exposed to five-plus times the current reference level"
If just 0.1% of that eventually ends up in a human (remembering many plants humans eat, like potatoes, bioaccumulate lead. Also, some lead may be consumed multiple times, since biosolids are used to fertilize crops, allowing the same lead to be consumed twice), the dose is still 100x the daily max consumption for every single american.
Good to get rid of it? Yes. A serious factor in society wide human lead exposure? No.
Leaded avgas mainly benefits turbines, which are a minority of GA planes but the majority of avgas users, because they're the always-running commercial subset.
The benefit is in time between overhauls. Every replacement fuel has resulted in more engine deposits and more maintenance -- essentially requiring $20K overhauls at 1,500 hours instead of 3K. For non-turbine GA, typically age catches up to the engine before hours, but for commercial turbines it can be a make-or-break decision, since a company might own only one or two.
Reid-Hillview airport in San Jose is an example of an airport closed over leaded fuel concerns, because they reportedly found an increase in lead in children's blood in a few who lived right next to the airport. That increase was minimal compared to elevated levels found in Oakland and elsewhere due to ingestion of 60+-year-old leaded paint, but it's essential to remove whatever sources there are.
The EPA has often complained, but the FAA has persisted. This particular move is noise before the next election (timed for the just-approved FAA appointee). It's unclear if it will result in anything faster than the decades-delayed process already in play, but it does give communities huge leverage in their lawsuits.
Local airports often have a lot of land being used for essentially nothing. When local communities take federal money to develop or maintain airports, they legally agree that the airport is to remain in near-perpetuity. It can take decades of refusing federal money to get out from those obligations. The redevelopment opportunity presented by closing an airport in San Jose or Santa Monica is in the billions of dollars. So there are strong economic interests supporting anything that turns a community against the local airport. And since few people want to have planes overhead, those neighborhoods are typically lower-income and often under-represented politically, raising environmental justice concerns and making for concealed politics as monied interests fund advocacy campaigns and scientific research.
Commercial turbine operators, GA owners, and local businesses using general aviation typically have fixed assets that commit them to protecting the airport.
The price of avgas runs 50-150% over automotive fuel. For refiners, it's a production shift and a run that lasts 1-2 weeks per year (and hence some storage costs as well). They also have fixed assets, though distribution networks have in some cases been outsourced in anticipation of moving in or out of the avgas market. They do it mostly to keep people happy, since it's not a big profit maker.
A big issue is ethanol. It's seasonally mixed into automotive fuel almost everywhere, but it attacks most of the current fuel systems. With engine re-certification for avgas, there are only 1-3 manufacturers running a few engines through time on test beds and some pilot programs. That's much, much easier than retrofitting fuel systems of many, many models of planes. In most cases, the manufacturer is no longer in operation, or they would love to see the old planes die so they can sell new ones (often having bought minimal name and assets out of bankruptcy).
Electric is unlikely to replace turbine ICE unless the energy density improves in ways that would transform the entire world. It's more likely smaller jet engines could replace them, but it's not clear who would do that engineering for a relatively small market.
So a pessimistic prediction is that this might help some local land grabs, but is not likely to help a lot of kids. Let's hope for more than that.
Eh? No. Turbine (i.e. jet) aircraft engines burn Jet-A, which is essentially kerosene and doesn't have any lead in it. Jet-A is not avgas. Reciprocating piston aero engines use 100 octane low lead avgas (today). That's the subject of the EPA thing in the article.
Leaded gas should never be burned in a turbine or for that matter any engine not specifically called for it. I've known motorcycle owners who do it, the spark plug, cylinder head, & piston wind up covered in a layer of lead
It should have been banned long ago.
[1] https://en.wikipedia.org/wiki/Lead%E2%80%93crime_hypothesis [2] https://en.wikipedia.org/wiki/Lead_poisoning