First of all, I’d like to wish everyone a healthy and Happy New Year.
It seems as I get older the years seem to come and go much faster than they used to, but someone once told me that life is like a roll of toilet paper — “the closer you get to the end, the faster it goes” — and I believe that they knew what they were talking about.
So, having been around this exciting industry that we all find fascinating, I’d like to offer some personal opinions on what I see happening these days.
I think you’ll agree with me that one of the most talked about things these days is the aviation fuels issue.
From my experience, this fuels subject has been going on for the better part of 50 years, if not longer. I vividly remember being pounded on at EAA AirVenture Oshkosh for many, many years as to why Lycoming wouldn’t approve the use of “car gas” in its engines.
We’ve been up and down the boulevard on this subject and the discussion is still ongoing, but with different players coming into the mix. I think most of you know that most internal combustion engines may run on almost any fuel that can be ignited, but the most important issue is whether it is safe and will work under all sorts of conditions.
You can get into all sorts of deep technical and chemical discussions — which are way above my head — but the basic fact remains: We must have a safe fuel that is capable of being produced and distributed at a reasonable cost.
Please note that I said cost and not price, in which there is a big difference.
I’m certain that those who currently produce and distribute aviation fuels are capable of supplying the market with viable safe products, but it sure isn’t that simple. Remember, when you can’t make a profit, you are out of business.
When you really stop and think about this challenge we have, it’s truly mindboggling as to what all has to be taken into consideration. Think about establishing a standard specification that must be repeatable. Think about all of the materials that must be tested for compatibility.
With that in mind, the engine may be the easiest thing to make it through the certification process.
I remember many of those discussions at Oshkosh over the years when the mindset was that the FAA was going to ban aviation fuels because of the lead content and, yes, we did see some changes when 100LL came to market.
I can go way back to the 1970s when this was the discussion. My response to those at the time was “I’ll be retired before that ever happened” and here we are still talking about the same subject many years after my retirement.
I think at the time most folks thought whatever fuel would replace the leaded fuels would be — hopefully — cheaper. I’m here to tell you that any fuel produced from now on will not be cheaper if it is compared to present production and distribution costs.
You may think I’m talking out my exhaust, but I think this situation is much more of a challenge than people would like to believe.
My final comment is this: Having two sons, it was a real challenge to bring them up, trying to teach them the difference between “needs and wants.” Maybe that’s where the general aviation fuels situation stands today.
Just how much of an impact does our use of 100LL really impact our environment? So, it begs the question: Do we need it or just want it?
In the big scheme of things, some would say “that our government certainly knows what’s best for us,” but in this case, I have my doubts.
The path to UL avgas is sheer torture to navigate or understand. Regardless of whether we accept the significance of leaving lead in fuel that is used in tiny quantities compared to mogas, the fact is that the lead just has to go. That environmental train has left the station and there is no calling it back. Why hasn’t it happened already given the fact that several safe alternatives seem to be available. 94UL will keep a large of percentage of airplanes out there quite happy – our 150’s O-200 was designed for 80/87! How many people know that 100LL has four times the lead of 80/87. Most pilots I’m guessing are totally confused by the whole sad process. Let’s just get it over with and make the transition!
Understand I am far from the stereotypical tree hugger. But I do love trees. And fresh air. And clean water. And uncontaminated dirt. All that stuff! And it’s hard for me to conceive that we wouldn’t be better off if something called tetraethyllead was eliminated from our presence. However I’ll leave that entire argument to the science experts and redirect to my airplane.
I’m only guessing now, but I’d ‘guess’ most of the readers here are too young to recall the dramatic effect of removing lead from auto gas back in the late 60s/early 70s. We fought it tooth and nail, mainly due to the poor performance from low compression engines that could burn the stuff. From 1970 to 1974 horsepower was nearly cut in half. That would eventually change as the Detroit and Japanese auto wizards figured it out.
But the interesting thing that we immediately HAD noticed was how much cleaner was combustion and oil. Oil still looked pretty good at 2000 miles. Spark plug fouling virtually went away. Recommended intervals for engine tune-ups were doubled. As development continued we spent less and less time under the hood. Today I seldom open it up – I don’t even check my oil anymore! Innumerable things evolved in auto engine manufacturing to achieve the level of dependability we have today. I’m no scientist nor engineer, but I doubt this would be the case if we still had lead in auto gas; the stuff is simply nasty.
All this blah blah blah simply to say that if aviation can transition to an unleaded fuel that performs as well as the GAMI tests imply, -sign me up!!!
From the Rotax maintenance Manual
The spark plug maintenance interval for a Rotax aviation engine depends on the type of fuel used:
100LL avgas: Inspect spark plugs every 50 hours and replace them every 100 hours
Unleaded auto fuels: Replace spark plugs every 100 hours
If you use Avgas for more than 30% of the time, you should perform more maintenance on your Rotax engine, including:
Changing the oil and oil filter every 50 hours
Inspecting the slipper clutch every 600 hours
Using Avgas can cause deposits in the cylinders and crankcase, which can increase the likelihood of corrosion.
I’m sorry, but I still say the business of removing the lead out of 100 ll is still all about money, not lead. If people would pay $10.00 per gallon of gas without complaining there would be plenty of 100ul at any airport anywhere anytime. But the problem isn’t the lead, its getting a lot of money for the fuel in order to make certain people rich beyond comprehension. Back in the 50s the price of 100ll was .39cents per gallon from Standard gas stations all over the nation. everybody at the drag strip would use 100LL in their cars, it burned very good, even Ethel gas was .34cents per gallon it was 94 obtain, it would burn very good getting about 40 miles per gallon in the average six cylinder car, today the people that produce gasoline cant make all the money they want per gallon, so they wont produce 100ul at a reasonable price, so they just wont budge, and the heck with the public, we can continue bitching and complaining, but until the producers of 100ul get the high prices of a gallon of 100ul that they want we will continue to write these stupid articles. We the people are slaves to these companies that we have allowed to succeed in alloying them to go beyond reasonable measures. Greed has no mercy.
The current value of $0.39 in 1950 is $5.24 according to https://www.bls.gov/data/inflation_calculator.htm
If a source of UL fuel becomes available at an airport near me that is compatible with my O-360, I’ll get the STC and use UL fuel. Currently, I don’t know even where to find it in the Tucson area.
The annual consumption of AvGas is miniscule compared to that of MoGas. In the US in 2022, 134 billion gallons of MoGas were consumed, vs only .19 billion gallons of AvGas, yet huge amounts of money are being spent to develop unleaded AvGas in order to “save the world”. Someone is making huge profits from this so-called eco-friendly endeavor!
It was bad enough when 80/87 octane AvGas was discontinued, and those engines designed to use it were forced to drink 100LL. It got so that I was pulling jugs off small Continental engines in my sleep to replace burned valves, and honing valve guides and replacing bent pushrods in carbureted Lycoming engines due to seized valves. And keeping carbon deposits out of O-235-L2C engines was an exercise in utter futility! Oh, and customers were thrilled (not!) with all the added maintenance costs!
Everytime that the Powers That Be mess with AvGas, there are problems!
On average, I burn around 5500 gals/yr. I have absolutely no interest in using the UL fuel. It won’t be somehow better or safer or more environmentally friendly or any less expensive. It’s not going to increase my TBO. My plane has soft seats in the valves. I’m not interested in changing them. I’m not interested in applying and paying for an STC. I’m not interested in patronizing airports that won’t sell anything but, UL. I wonder if anyone else feels the same way..?
There.
Seems to me that there are less and less GA planes in the air every year. From what it was 20 years ago will never come back. I would like to see some documentaion on how many PPM of lead is in the atmophere. JMO
When 100LL burns, the TEL is converted to lead-bromide by the ethylene-dibromide added to the fuel.
Lead-bromide quickly cools to solid particles as it exits the exhaust system, and they fall to the ground. Some of it collects at the exhaust pipe tips.
So no lead remains in the atmosphere for long.
Mr. Fisher: On the other hand your comments are overly optimistic, and you offer no facts to support you claims about cost/price/expense.
“the cost of refined components that make up G100UL is currently in the range of $0.90 to $1.10 more than the cost of components used in 100LL.” …aviationconsumer.com -Other estimates can be found by googling.
I think Mr. McBride’s comments were more on the order of explanation, and maybe frustration, that he has had to observe a lifetime of experience before the ‘wheels of progress’ seem to be moving.
Here is what Rotax jas to say about leaded fuel While Rotax aviation engines can run on leaded fuel, it’s not recommended. Leaded fuel can cause lead sludge to build up in the engine’s oil tank and reduction gearbox, which requires additional maintenance. Leaded fuel is also incompatible with the recommended synthetic oil, which can’t hold lead in suspension.
Exactly! Had a big meeting about 30 years ago at Lycoming on this very subject!
Are we beating the wrong bush? I think so.
I wonder: why is everyone so fixated on spending so much money, time and resources (and in boring never ending discussions as stated in this article) in finding a fuel that works on a relatively small percentage of dynasauric high powered engines that must use high octane leaded fuel when it is my understanding that a majority of engines out there will run fine on lower octane unleaded fuels?
I am dismayed to see Lycoming still selling the same old engines at outrageous prices, that people continue buying, that may not even work when leaded fuel becomes unavailable (and that will happen one day, or else, it’s alternative will be outrageously expensive). Lycoming could be developing and selling new engines that run just fine on unleaded fuel instead of inexplicably being successful in just convincing everyone that the solution is to come up with some fancy expensive cocktail that will keep their ancient designs running so that they can keep selling them without spending a penny on R&D.
It is my understanding (could be wrong) that 68% of the piston powered GA fleet could switch to 91UL today. The issue, of course, is that airports don’t really sell it (I know, I have a Rotax powered airplane). I wonder if instead of spending so much money in “finding” a 100LL replacement the government “encouraged” the installation of fuel farms at airports that supplied aviation grade 91UL fuel so we could switch and reduce this problem by 65% right away? Contrary to the writer’s pessimism about aviation fuel being more expensive in the future, maybe it doesn’t have to be that way for most of us (relatively speaking).
So, what about the other third of the fleet? Well, I am no expert on the subject but, by looking at my airport’s ramp, it seems that a lot of the high-powered piston fleet is already being replaced by turboprops or jets. Would a 94UL, which is popular in Europe, increase the current 65% to something much higher? Would that move encourage US engine manufacturers to come up with alternatives to run unleaded fuel (Rotax and UL Power engines run on low octane car gas and are catching up on the HP department)? Having worked as an Engineer in projects together with Continental on applications for their diesel piston engines that is another viable source of powerplants. And finally you still have the new high octane unleaded fuel “cocktails” being developed which could be in place when 100LL is finally banned to power the few remaining that need high octane. BTW, since humans are a creative bunch, there is a chance someone will come up with STCs to modify engines that need 100LL to run lower octane unleaded fuel. May options to very quickly make that 65% closer to the 85% it is in Europe.
Me, I just built myself a Rotax powered airplane so I can get inexpensive “aviation” fuel, I am ready to go.
Mr. JeffO
Because you asked here is a statement made by Rotax that I lifted regarding the TBO using lead contaminated fuel.
A Rotax engine’s Time Between Overhaul (TBO) is significantly impacted by using leaded gas, as it is strongly recommended to use unleaded automotive fuel with a Rotax engine, as using leaded fuel can lead to lead buildup in the engine’s oil system, requiring more frequent maintenance and potentially reducing the engine’s lifespan, thus impacting the TBO; essentially, using leaded gas can lower the effective TBO of a Rotax engine
Need vs want is a very interesting point. We know the impact of leaded aviation fuel has been greatly exaggerated and is being used as a pinch point to curtail our operations and shut down airports. Funny how our life expectancy was longer when we had lead paint on our walls and children’s toys. How about taking the toxins out of our food before worrying about the fuel?
Here you go:
From GAN in 2012, I’m sure Ben won’t mind.
‘Crumbling paint a bigger threat’ than leaded avgas
By Ben Sclair · January 30, 2012 ·
“More lead goes into the air here at Boeing Field than anywhere else in Washington state,” says KUOW’s John Ryan reporting from Ruby Chow Park under the flight path of Seattle’s Boeing Field (BFI).
In his story on KUOW titled, “Flying The Leaded Skies: Small Planes Still Pour Lead Into America’s Air,” Ryan takes us on a journey regarding leaded fuel.
Ryan continues, “Avgas account for less than 1 percent of the nation’s liquid fuel use. Yet…belch out half of all the lead going into the nation’s air.”
The report continues at Van Asselt Elementary, just one-quarter mile from Boeing Field. Marie Lynn Miranda is an environmental health scientist and a dean at the University of Michigan. Based on research Dean Miranda has conducted in North Carolina, she’s found, “Living close to an airport can increase your blood lead level anywhere from 2 to 4 percent. That’s small. But we’re getting more and more evidence that indicates even very small amounts of lead is bad.”
In the eight-minute, forty-two-second story, this next sentence seems almost a throw-away… “Miranda says lead from crumbling paint in old buildings remains a much bigger threat to children’s health.” That sentence can be read about a 1/3 of the way into the story, yet that’s the only mention of the “much bigger threat”.
So here is what I don’t understand. Why didn’t reporter Ryan stop the reporting and attempt to tackle the “much bigger threat”? I’ve placed a call into John Ryan to get that answer.
I’ve also emailed Dean Miranda seeking clarification on how much bigger a threat is “crumbling paint” in “old buildings.”
When I find out, I’ll let you know. If anyone out there has connections to either, I’d appreciate your passing my queries along.
This article shows some pessimism for some reason. If the final decision on unleaded fuel was to change to UL 94 it wouldn’t necessarily be more expensive than the current 100 LL. First of all, it wouldn’t include the expensive component of lead, nor would it have to be transported in such a way that the lead contaminate would result in additional cost. For example, pipelines won’t let leaded fuel be distributed through that system. Also considerable savings can be had by not using lead in fuel, such as oil changes could be doubled, and TBO’s would go up.