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Leaded under global attack ... !

wcalvert

Well Known Member
From the front page BBC:

"There is now no country in the world that uses leaded petrol, the UN Environment Programme has announced.

... Most high-income countries had banned the fuel by the 1980s, but it was only in July that Algeria - the last country still to use leaded petrol - ran out.

UN Secretary-General António Guterres called the eradication of leaded petrol an "international success story"."

Feel like I just missed getting run over by the bus. They'll be coming for us next!
 
I saw a similar article. The last line said (paraphrasing) "small aircraft still use leaded aviation fuel".

Most people find it convenient to forget that there is also racing fuel with lead in it. It's used in significantly lower volumes than 100LL though.
 
Lead

Ground Zero in the US is Reid-Hillview in San Jose CA. Lawsuit in the works based on lead poisoning claims. They want to repurpose the land for housing. 124 based aircraft.
 
Most RV aircraft using Rotax or Lycoming Parallel valve engines will not need to worry about 100LL going away. According to Lycoming Service Instruction 1070AB (the latest version when I post this) are already approved for unleaded fuel. Most of these engines can run on alcohol free 93 AKI automobile fuel according to the Lycoming Service Instruction.
 
Most RV aircraft using Rotax or Lycoming Parallel valve engines will not need to worry about 100LL going away. According to Lycoming Service Instruction 1070AB (the latest version when I post this) are already approved for unleaded fuel. Most of these engines can run on alcohol free 93 AKI automobile fuel according to the Lycoming Service Instruction.

The problem, at least from my side, is not engine compatibility, but availability at airports.
 
The problem, at least from my side, is not engine compatibility, but availability at airports.

Chicken/Egg problem.

If 100LL is truly going away, the airports will change their existing infrastructure to mogas to serve the portion of the market that CAN be served, as versus abandoning it and serving nobody.
 
If engine and airframe manufacturers would stop making or specifying engines with high CR that require avgas it would be a start. You don’t see the auto industry getting around still building engines that need lead. Yeah sure, you really need that 8.7 instead of 8.5 CR. If they just said that new or re manufactures engines had to be built to take high octane mogas, within a decade the transition would have been made, the way it did in the auto industry. Before I hear the lead lovers go boo hoo about the fact that their 1954 bla bla aeroplane needs lead and they are going to have to make special arrangements to get the fuel in drums or that they will have to modify their engine timing or CR to use mogas, those of us that ONLY use mogas today have to jump through the same hoops now because we can not buy unleaded fuels at most airports.
Time to get with the 21st century, because the social license to continue to expose others to lead is rapidly expiring.

Tom.
 
Half the problem is who consumes 100LL. Us little RVs and most trainers are flying around burning 10gal/hr or less in lower compression engines and are mostly fine with 91-95 octane.

Those with engines that actually need 100 octane consume much more of it. Cabin class piston twins, Navajos and such with big turbocharged engines burn 35-40gal/hr. Warbirds are significantly more thirsty again. Every time you see a Cessna 421 fly past, that's 5 RVs worth of fuel consumption. Many of them for commercial operators that fly the airframe 1000hrs a year as well.

I don't have exact numbers, but I'd wager that a large portion of the 100LL consumed is in engines that need it to be 100 octane. If we were to just abandon those consumers because it doesn't affect us, would dramatically decrease the demand for this "new" avgas. Airports will begin to drop the fuel due to low demand and then we all loose. It already happened in parts of Europe and much of Northern Canada.
 
... Airports will begin to drop the fuel due to low demand and then we all loose. It already happened in parts of Europe and much of Northern Canada.
I have zero visibility into the economics, but my tiny airport/flying club installed a new fuel station that delivers 100LL, 91UL, and Jet-A. For some reason adding a 3rd fuel always seems to be "off the table" due to economics, but perhaps that's a reasonable solution.
 
The problem, at least from my side, is not engine compatibility, but availability at airports.

Yes. I would use 91-93 octane Aviation-specific unleaded fuel in a heartbeat, but only if it was available on the fuel truck at my airport.
 
The problem, at least from my side, is not engine compatibility, but availability at airports.
Bingo. And availability in the region period, if the EPA has declared it a non attainment area. Only thing available for 100 miles from my home is the reformulated garbage.

As for the health effects, dubious on the whole as compared to smoking (which many, many young people are now picking up), junk food, soft drinks, food preservatives, alcohol, vaping, sitting on your backside 18 hours a day playing video games, skateboarding, motorcycle riding, having an electromagnetic energy transmitter in your hands and pocket 24-7, riding bicycles on the street with cars, etc, etc.
 
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I was involved with a fair amount of gliding in my younger days. Being the one who held the wing tip of the glider until past running speed was always a fun job. Fantastic smell of the 100LL avgas exhaust from the towplane too.

To think of how much many brain cells didn't develop....

Since the FAA seems to be struggling with developing a drop-in 100LL replacement, can we task the EPA with developing the new fuel?
 
I was involved with a fair amount of gliding in my younger days. Being the one who held the wing tip of the glider until past running speed was always a fun job. Fantastic smell of the 100LL avgas exhaust from the towplane too.
To think of how much many brain cells didn't develop....
Since the FAA seems to be struggling with developing a drop-in 100LL replacement, can we task the EPA with developing the new fuel?

Careful what you ask for. Their answer will probably be an extension cord!
 
You just described my wasted youth ... !

Didn't say get rid of it all. Just trying to keep it all in perspective. There's a price to pay for a modern lifestyle. And an even bigger price to pay for a primitive lifestyle.
 
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If engine and airframe manufacturers would stop making or specifying engines with high CR that require avgas it would be a start. You don’t see the auto industry getting around still building engines that need lead. Yeah sure, you really need that 8.7 instead of 8.5 CR.
Except a lot of the new automotive engines *are* using high CR. My Mazda3 is 9:1, and in Europe it's available with a 10 or 10.5:1 CR. No, not the Diesel.
 
Except a lot of the new automotive engines *are* using high CR. My Mazda3 is 9:1, and in Europe it's available with a 10 or 10.5:1 CR. No, not the Diesel.

I believe the new Mazda Engines are combustion ignition (ignition with no spark), so they are not a diesel because they use mogas, but they don't use a spark to initiate combustion. This improves mileage and smog.
 
There are Mazda diesels but compression ignition/direct injection is nothing new. Their new family of engines are direct injection gasoline engines and for the most part are leading the industry in efficiency; in so much that Toyota was (is?) in negotiations to license the technology. Directly injecting in multiple ports, better utilization of Exhaust gas Recirc = higher Cp than air for better heat transfer and lower N2 available compared to fresh air in the combustion process to lessen NOx emissions.

Auto CR comparisons aren't really applicable here. Smaller bore and higher frequency combustion events (higher rev'ing) are intrinsically less prone to ignition. We are limited by direct drives and sonic prop tip speeds. The inability to reasonably detect knock in our PPs limits the margins/distance we can dance next to the detonation cliff.
 
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Except a lot of the new automotive engines *are* using high CR. My Mazda3 is 9:1, and in Europe it's available with a 10 or 10.5:1 CR. No, not the Diesel.

Modern auto engines are also liquid-cooled and computer-controlled, with knock and other sensors and better cylinder head designs. You can get away with a lot when the ECU can adjust timing and mixture on the fly to avoid problems.

It would certainly be possible to put this technology into a clean-sheet aircraft engine. However, I'm not sure it would be able to be air-cooled, and in any case the effort required to certify it would be so expensive, and the available market so small, that it would never make commercial sense.

====

I suspect one of the reasons for the near-halt to aviation piston engine development (beyond perverse regulatory incentives to not develop them) is that the bigger, more powerful (and more profitable) engines got supplanted by turboprops. Get much past the 6-cylinder range or so, and you'll start running into turboprops that are lighter, more powerful, and more reliable.

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My understanding is that G100UL works just fine as a drop-in replacement. However, it's slightly more dense than 100LL (on the order of 3% or so) so the FAA apparently won't accept it without an STC. Changes weight and balance computations, I guess...
 
My understanding is that G100UL works just fine as a drop-in replacement. However, it's slightly more dense than 100LL (on the order of 3% or so) so the FAA apparently won't accept it without an STC. Changes weight and balance computations, I guess...

Well that's irritating. Did they forget that 100LL changes density with temperature and is likely off my more than 3% on most days anyway? Our 6lbs/gal is only good at 15°c, and that's not terribly common.
 
Ha?

Well that's irritating. Did they forget that 100LL changes density with temperature and is likely off my more than 3% on most days anyway? Our 6lbs/gal is only good at 15°c, and that's not terribly common.
well DUH!

I guess this blows the Specific gravity requirement to be the same as 100LLout of the water?
 
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