Transition to UL Fuel

Phase 1: Throw stuff out there.
Phase 2: See what sticks (and what melts).
Phase 3: Ramp down sales of 100LL to zero in the CONUS and islands.
Phase 4: Ramp down sale of 100LL to zero in Alaska.

Apparently, we are currently somewhere between phase 1 and phase2.
 
There's a brief mention about the importance of the fuels being fungible with each other on page 21:

A particular concern that has been raised by stakeholders is the effect of mixing the various unleaded fuels.​
There will be significant operational challenges and risks if multiple fuels are authorized for the same aircraft​
but cannot be mixed. This scenario would likely introduce a risk of regional market segmentation that could​
become a significant barrier to National Transition. It could also increase the risk of misfuelling, raising safety​
concerns. For these reasons, the FAA may conduct intermixability testing of the various fuels in this phase. The​
fuel offerors are encouraged to also evaluate the intermixability of fuels as they become available.​

I think this is going to prove to be a major hurdle, and it doesn't seem like it's being addressed seriously. The fuel developers have no motivation to make one fuel play nicely with another. Each wants a winner-take-all outcome. If anything is to happen, the FAA will have to force it, and this wishy/washy stuff about "the FAA may conduct intermixability testing" isn't going to cut it.

Imagine trying to drive your car cross country, but being unable to put Chevron juice in with Shell or BP.
 
It's not so much that mixing the different fuels will cause problems, probably it won't, but they haven't proved and documented that mixing is OK.
 
I respect George Braly's reasoning for why he hasn't put G100UL through public testing but I wish he'd do it, because the upshot is that we effectively won't have the fuel available anyway, so it's a bit of a pyrrhic victory to keep it away from competitors by effectively keeping it away from customers too. Public testing by other parties would probably help clear out the FUD too regarding whether there are issues with seals and valves. Seems like funding one of the aviation universities to run a well-controlled study of various fuels in their aircraft fleet might be better than everyone standing around admiring the problem.
 
2030 seems awfully optimistic given the state of things. I think TEL production being extended and that deadline being pushed out is still a definite possibility.

Ultimately we’re just waiting to see what the various corporations and the FAA come up with. I just hope we’re not stuck with $7/gal avgas at the end of this.
 
cowman said:
2030 seems awfully optimistic given the state of things. I think TEL production being extended and that deadline being pushed out is still a definite possibility.
Click to expand...
Given that the only TEL production is in the UK and the USA is throwing punches at its allies right now with tariffs, it would be ironic if the UK decided to put a large tariff on TEL and watch how that plays out. Or just shut down production, since it's an environmental/safety nightmare to manufacture, I gather. Not sure I'd count on any extension of TEL production.
 
Scott Perdue had an excellent video about this last week:


ETA:
Seems like Swift and Lyondell are using ETBE as the octane booster. As I understand it, that additive has to be in a certain concentration to work, so it probably won't be miscible with G100UL or maybe even 100LL.

G100UL has its issues for sure, but the other fuels are going to require timing changes for high compression engines. That will reduce performance, which then has effects on everything from gross weight to takeoff distance.

I'm disturbed by the complete lack of any news on this. G100UL stumbled out of the gate, and it's been radio silence out of everyone since then.
 
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cowman said:
Ultimately we’re just waiting to see what the various corporations and the FAA come up with. I just hope we’re not stuck with $7/gal avgas at the end of this.
Click to expand...
Considering recent inflation--and recent 100LL replacement progress--"at the end of this" we'll be looking back at $7/gal gas with the fondness of nostalgia. "Oh, the good ol' days...."
 
Dana said:
It's not so much that mixing the different fuels will cause problems, probably it won't, but they haven't proved and documented that mixing is OK.
Click to expand...

I hope that’s true, but I rather doubt it. AFAIK, G100UL is the only one that has been shown to be compatible even with 100LL. If the other two can’t mix with 100LL, I’ll be surprised if they can mix with GAMI gas.
 
Jim K said:
Scott Perdue had an excellent video about this last week:


ETA:
Seems like Swift and Lyondell are using ETBE as the octane booster. As I understand it, that additive has to be in a certain concentration to work, so it probably won't be miscible with G100UL or maybe even 100LL.

G100UL has its issues for sure, but the other fuels are going to require timing changes for high compression engines. That will reduce performance, which then has effects on everything from gross weight to takeoff distance.

I'm disturbed by the complete lack of any news on this. G100UL stumbled out of the gate, and it's been radio silence out of everyone since then.
Click to expand...
Really nothing we didn't already know except that the lyondell basell fuel is much like swift's fuel and will require derating and timing changes. That should be a non starter and be told to GTFO

We've known the ASTM mandate doesn't do what people think. So what's the point of having it? And that's been Braly's hangup.

The radio silence from Gami is concerning. However, while we saw initial issues with it. We haven't continued to hear about those issues. Did everyone stop using it? Or are some of the issues a little exaggerated?

To expand on something Scott touched on. Who's looking out for us the owner directly affected by these fuels. Vp/lyondell is a faceless organization that won't even do interviews. Swift is only slightly better in that we can put a name to the company, Chris Dacosta.

Gami however is more "one of us". They're pilots and owners. They have a better understanding of how important not losing performance is. Now if only they can keep the paint on my plane.
 
Half Fast said:
I think this is going to prove to be a major hurdle, and it doesn't seem like it's being addressed seriously.
Click to expand...
They will be miscible, but the mixes should be tested for other problems that may come up such as degrading parts of a fuel system such as seals, bladders, and so forth.
AvNavCom said:
Given that the only TEL production is in the UK and the USA is throwing punches at its allies right now with tariffs, it would be ironic if the UK decided to put a large tariff on TEL and watch how that plays out.
Click to expand...
I see what you are saying, and I agree. The pedant in me simply notes that it would be an export tax rather than a tariff.
Jim K said:
Seems like Swift and Lyondell are using ETBE as the octane booster. As I understand it, that additive has to be in a certain concentration to work, so it probably won't be miscible with G100UL or maybe even 100LL.
Click to expand...
Assuming that "ETBE" = ethyl tert-butyl ether, this has long been used as an octane enhancer. It was used (along with the methyl ether) in the USA but these aren't used much now. The ethers are miscible with the hydrocarbons used in these fuels. The ethers have a particular odor and the the ethers gained a bad reputation when leaking underground tanks containing gasoline with this additive contaminated groundwater. The tanks were leaking prior to this additive but the ethere were very noticable. See: https://www.ncbi.nlm.nih.gov/books/NBK584747/#:~:text=Due to its environmental mobility,contaminated drinking water is possible.
Jim K said:
G100UL has its issues for sure, but the other fuels are going to require timing changes for high compression engines.
Click to expand...
These are the sort of issues I was thinking about in my first reply in this post. Why do you think timing changes are needed?
Half Fast said:
I hope that’s true, but I rather doubt it. AFAIK, G100UL is the only one that has been shown to be compatible even with 100LL. If the other two can’t mix with 100LL, I’ll be surprised if they can mix with GAMI gas.
Click to expand...
What do you mean by "compatible"? Why do you think they don't mix? Do they from two phases, like if one mixes gasoline with water?
 
AvNavCom said:
Given that the only TEL production is in the UK and the USA is throwing punches at its allies right now with tariffs, it would be ironic if the UK decided to put a large tariff on TEL and watch how that plays out. Or just shut down production, since it's an environmental/safety nightmare to manufacture, I gather. Not sure I'd count on any extension of TEL production.
Click to expand...

Tariffs are levied on incoming products. However, I guess an export tax could be enacted.
 
Cap'n Jack said:
These are the sort of issues I was thinking about in my first reply in this post. Why do you think timing changes are needed?
Click to expand...
honestly? Heresay and guessing. Scott makes that assertion in the video. Braly had said they 100R is lower octane than 100LL and won't be a drop in in high compression engines. D'Acosta said that "the high compression engines will be harder" and that they were just starting testing. My gut feeling is that if they were at all confident their fuel would be usable in high compression engines, they'd be shouting it from the rooftops and not saying, "we're working on it".
 
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@PaulMillner wrote an excellent post on BT that I hope he won't mind me quoting here:

There are some other subtleties here that need to be appreciated. Both Swift Fuels and Lyondell (the FAA’s PAFI fuel standard bearer) have very similar ether-based formulations. What both have shared is that their fuels will not deliver acceptable F4 octane, the 130 of 100/130, within the ASTM standard for determining F4 octane. If you let them fudge the test, then they can deliver detonation margin. But that creates a couple problems in the field with real engines.

If the ether-based fuels are tested using the ASTM protocol, then these ether-based fuels deliver an F4 of 110 octane or less… so a 100/110 fuel instead of a 100/130 fuel. Both Swift and Lyondell have acknowledged that as such, there are ~30,000 aircraft that can’t use the fuel, or about half of the 100LL demand.

To make it kind of work, Swift and Lyondell propose moving the goalposts. Instead of conforming to the ASTM F4 measurement standard, they propose instead to operate the engines 15% to 20% richer than the maximum richness allowed in the ASTM protocol. If you move the goalposts like that, then perhaps you can deliver 130 F4 octane.
However, our *aircraft* can’t operate 15% to 20% richer without significant modification. It’s not just a matter of turning up the fuel injection… most systems can’t be adjusted to operate that much richer, without coming up with some kind of as yet undefined modification. But even if someone can be induced to develop, and certify, such a modification, or new fuel injection hardware, then we then have a fungibility problem. Because a engine running 20% richer will produce less than rated horsepower if subsequently operated on 100LL. And if you have a mix of 100LL and 100-ether fuel in your tanks, you’ll need to puzzle out what fuel flow will deliver adequate horsepower while still avoiding detonation. That’s a fairly demanding task for a pilot… do we need to do an ether titration on each tank, and record that data for later use in flight to set fuel flows? That seems like a certification headache, if safety margins are to be maintained.
So moving the goalposts may seem appealing, but creates other challenges.

Paul
Click to expand...

So the octane isn't there. Solution will be dumping more fuel through and not being interchangeable with 100LL, or reducing timing/power.
 
Racerx said:
Really nothing we didn't already know except that the lyondell basell fuel is much like swift's fuel and will require derating and timing changes. That should be a non starter and be told to GTFO
Click to expand...
Absolutely. If it isn't a "drop-in replacement" it should be abandoned for the next thing.
Racerx said:
We've known the ASTM mandate doesn't do what people think. So what's the point of having it? And that's been Braly's hangup.
Click to expand...
It doesn't matter what you or I "know." It matters what Lycoming and Continental want. As for George, he may or may not be the smartest man in the room, but he'll have to swallow some pride if he wants to sell his product.

Racerx said:
The radio silence from Gami is concerning.
Click to expand...
The only thing worse than their silence is their talking. They proclaimed G100UL as "commercially available," which was kind of true in a technical sense, but not in a real-life way. "Commercially available" unleaded would mean that 100LL was instantly illegal in California, forcing everyone to buy both the GAMI STC and the fuel. Fortunately, a relevant judge disagreed with GAMI.

As more people started using it and developing fuel leaks and paint stains, George blamed owners. In online discussions, he may be dismissive, condescending, or sarcastic. One suspects he's the same way in meetings.

I've been saying for years that GAMI desperately needs PR help. If they were half as intelligent in communication as they are in the lab, we'd have been burning G100UL exclusively for 2 years or more by now.
 
OneCharlieTango said:
The only thing worse than their silence is their talking. They proclaimed G100UL as "commercially available," which was kind of true in a technical sense, but not in a real-life way. "Commercially available" unleaded would mean that 100LL was instantly illegal in California, forcing everyone to buy both the GAMI STC and the fuel. Fortunately, a relevant judge disagreed with GAMI.

As more people started using it and developing fuel leaks and paint stains, George blamed owners. In online discussions, he may be dismissive, condescending, or sarcastic. One suspects he's the same way in meetings.

I've been saying for years that GAMI desperately needs PR help. If they were half as intelligent in communication as they are in the lab, we'd have been burning G100UL exclusively for 2 years or more by now.
Click to expand...

Perfect summary.
 
Racerx said:
The radio silence from Gami is concerning. However, while we saw initial issues with it. We haven't continued to hear about those issues. Did everyone stop using it? Or are some of the issues a little exaggerated?
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Has anybody been able to buy it? Does KRHV still carry it? Is it available anywhere else?

I wonder how many STCs GAMI has sold, and I wonder how many gallons of G100UL have been burned. I would guess the answer to both is, "Few."
 
Mikey52 said:
Tariffs are levied on incoming products. However, I guess an export tax could be enacted.
Click to expand...
Tariffs can be import or export. In this instance, you're entirely correct that it would be an export tariff.

Edit: Drat, I guess technically it is "export tax". So, despite my best efforts, I've learned something today. :D
 
I have the STC for ul 94,try finding it ,and when you do your looking at 8-9 dollars a gallon. It does mix well with 100ll
 
Jim K said:
honestly? Heresay and guessing. Scott makes that assertion in the video. Braly had said they 100R is lower octane than 100LL and won't be a drop in in high compression engines. D'Costa said that "the high compression engines will be harder" and that they were just starting testing. My gut feeling is that if they were at all confident their fuel would be usable in high compression engines, they'd be shouting it from the rooftops and not saying, "we're working on it".
Click to expand...
The only testing swift has done on the io520 engine is use the only model already approved for ul94. To quote @Half Fast , if they could test it, they would.

With as loud as D’Acosta is, if it worked in the high compression engines. We'd have heard about it.
 
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OneCharlieTango said:
Absolutely. If it isn't a "drop-in replacement" it should be abandoned for the next thing.

It doesn't matter what you or I "know." It matters what Lycoming and Continental want. As for George, he may or may not be the smartest man in the room, but he'll have to swallow some pride if he wants to sell his product.


The only thing worse than their silence is their talking. They proclaimed G100UL as "commercially available," which was kind of true in a technical sense, but not in a real-life way. "Commercially available" unleaded would mean that 100LL was instantly illegal in California, forcing everyone to buy both the GAMI STC and the fuel. Fortunately, a relevant judge disagreed with GAMI.

As more people started using it and developing fuel leaks and paint stains, George blamed owners. In online discussions, he may be dismissive, condescending, or sarcastic. One suspects he's the same way in meetings.

I've been saying for years that GAMI desperately needs PR help. If they were half as intelligent in communication as they are in the lab, we'd have been burning G100UL exclusively for 2 years or more by now.
Click to expand...
George is a lot of things, and stubborn is definitely one of them.
 
Half Fast said:
GAMI has demonstrated that their fuel can be mixed with 100LL. AFAIK, the other two have not demonstrated that, and I think they would if they could.
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I responded to this in my earlier post:
Cap'n Jack said:
They will be miscible, but the mixes should be tested for other problems that may come up such as degrading parts of a fuel system such as seals, bladders, and so forth.
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Perhaps the other companies haven't responded because it is, to them, a no-brainer. All of these fuels are made a mixture of alkanes (straight chain or branched), some alkenes, some aromatic compounds (compounds based on a benzene ring that will have other groups attached), and something to enhance octane (more aromatics, the ethers mentioned earlier, tetraethyl lead, or Methylcyclopentadienyl Manganese Tricarbonyl (MMT)). All of these are miscible in any amount.

GAMI may just be playing marketing games, too, by implying that the others haven't done the tests at all. If they didn't do the tests, it would be really stupid on their part since any miscibility issues would become apparent all too quickly. In addition to testing with 100LL, it is more important to test miscibility between all the potential fuel candidates because 100LL will go away. I'd also like to see aging tests. What happens if the fuel and mixtures of the various fuels are left in a hot or cold environment for a month or two?

In any case, there will be (has been?) testing done. As per the document linked by @Half Fast :
Testing is planned on up to three 100-octane, unleaded fuels as they can be obtained (GAMI G100UL, Swift Fuels100R, and LyondellBasell UL100E) and three leaded reference fuels (FBO 100LL, a minimum specification 100LL fuel, and a high-aromatic blend 100LL [min 15% aromatic by volume]). Each of the leaded fuels will serve as a reference fuel for comparison for that block of testing. Engine detonation, materials compatibility, and laboratory analytical testing and evaluation will be performed targeting key engines and materials that act as bellwethers for unleaded fuel analysis. The testing is divided into four blocks, with block one focusing on fuel fit for purpose and composition, block two focusing on engine testing, block three focused on materials testing, and block four being a toxicological assessment. The testing in block one will be performed on the neat unleaded fuels, referenced unleaded fuels and FBO 100LL, and 50-50 blends of two unleaded fuel candidates.
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This is from pages 29 and 30. Emphasis mine, and note that materials testing in listed in the tests. My opinion is that more combinations than a 50-50 blend should be tested.

OneCharlieTango said:
Absolutely. If it isn't a "drop-in replacement" it should be abandoned for the next thing.
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Good luck with that. While I agree with your comment, there's what the draft transition plan says about that (page 20 in the link at the start of this thread):

3.3.4 AIRCRAFT ALTERATIONS
Regardless of the process used, individual aircraft owners must take specific actions to implement the authorization to use unleaded fuel in their aircraft. Fuel limitations are indicated on a placard near the fuel tank access and are documented in the approved aircraft flight manual. Each individual aircraft must alter the placard and any associated limitations and may need to make other aircraft alterations to ensure compatibility with a particular fuel. The information below highlights the alteration processes for use by various portions of the fleet:
• For aircraft with a standard airworthiness certificate, this is an aircraft alteration that is accomplished under 14 Code of Federal Regulations (CFR) part 43 and must be performed by an authorized mechanic, repairman, or certificated repair station (14 CFR 43.3). The authorized person confirms the applicability of the approval or authorization to that specific aircraft, replaces the fuel placard, revises the flight manual and instructions for continued airworthiness as appropriate, and records the alteration action per 14 CFR 43.9. If other aircraft changes are required to use the fuel, they would be made as part of this alteration. If the aircraft alteration is a major change, the alteration is also signed off by an individual with inspection authorization (IA) and reported to the FAA on Form 337 per 14 CFR43.7 and 43.9.
• For special light-sport aircraft, this is an alteration that is accomplished under 14 CFR part 43 and must be performed by a light-sport repairman (14 CFR 65.107) or mechanic (14 CFR 65.73). The light-sport repairman or mechanic confirms the applicability of the approval or authorization to that specific aircraft, replaces the fuel placard, and revises the flight manual and instructions for continued airworthiness as appropriate. If other aircraft changes are required to use the fuel, they would be made as part of this alteration.
For aircraft with a special experimental airworthiness certificate, including experimental light-sport and amateur-built aircraft, the pilot can determine the eligibility of a fuel for their aircraft and replace a fuel placard as appropriate. For aircraft with an experimental airworthiness certificate, owners are responsible for ensuring their aircraft is compatible with the new fuel. Owners may obtain data to support that determination from a Fleet Authorization or from a fuel offeror for fuels approved for use under TC/STC.
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Again, emphasis is mine. You may need to expand the quoted material ("click to expand") to see the highlighted text.
 
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Racerx said:
We've known the ASTM mandate doesn't do what people think. So what's the point of having it? And that's been Braly's hangup.
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Braly is a smart guy, but he can be his own worst enemy. And yeah, you can write a spec for anything. I remember a training session on ISO 9000 or one of those, the presenter pointed out that you could manufacture concrete life jackets under ISO 9000. They would all be delivered on time and sink at exactly the same rate.
Cap'n Jack said:
Assuming that "ETBE" = ethyl tert-butyl ether, this has long been used as an octane enhancer. It was used (along with the methyl ether) in the USA but these aren't used much now.
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MTBE was commonly added when states required "oxygenated" gasoline for emissions purposes, until environmental or health issues came up, at which point many switched to ethanol. Both are oxygenates, and both boost octane.
frfly172 said:
I have the STC for ul 94,try finding it ,and when you do your looking at 8-9 dollars a gallon. It does mix well with 100ll
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It should mix OK; it's just 100LL without the lead. There was one airport around here thant had 94UL, I used it once when passing through. At the time it was actually cheaper than 100LL but now they no longer sell it. I suspect they bought one tank truck load and the price was based on the price when they bought it.
 
I've been keeping up with this topic for quite a while now. I think it's reasonable to conclude that if there was a good solution, it would have been adopted by now. None of the four companies who have attempted to produce a "drop-in" replacement have succeeded in mass-marketing a product. Here's my guess as to how this will play out nearing 2030.

A more expensive fuel with somewhat less detonation resistance than 100LL will be grudgingly accepted. Some of the high-compression or turbocharged engines will face derating, and new performance charts. That will cost money, and require someone to do the work. Expensive, and potentially not worth the effort. There may be orphans. I think that water or methanol injection systems are not feasible.

What amazes me is the head-in-the-sand attitude manufacturers are taking with this looming deadline. Cirrus continues to churn out planes that need a fuel that will be unavailable shortly, simultaneously warning pilots about alternative fuels. Brilliant.

The vast majority of the world does not care if a big chunk of the piston fleet is grounded. How many politicians are going to lose their seats when the one remaining tetraethyl lead plant shuts down without a substitute? We all know the answer to that. It's unfortunate that this situation even exists give our level of technical expertise, but if I had a plane that really required 100 octane fuel, I'd be trying to sell it....soon.
 
737steve said:
. . . but if I had a plane that really required 100 octane fuel, I'd be trying to sell it....soon.
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A very large fraction of fuel is burned by those that require 100LL. Some say 80%, but I don't know where that came from. If that's the case and we adopt a policy that renders those aircraft useless, the piston infrastructure collapses. Safe to say that, even if your airplane doesn't require 100 octane, you need it to be available.
 
OneCharlieTango said:
Some say 80%, but I don't know where that came from.
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I looked into it a while back. It's from the 80s/90s when checks were flown overnight and other stuff like that.
I highly doubt that figure is accurate today.
Also, a good number of aircraft need 100LL on paper, because they need more than 87 but nothing else was available below 100 when certified. Case in point: an O-320 with "high compression" pistons. It'll run just fine on premium (or even mid-grade) mogas, but in the avgas world, it's 100LL or nothing. Yes, we still have the UND valve recession incident, but I still think some of it was caused by the way they operated those engines. Otherwise you'd see a lot of that stuff being reported by the mogas users.
 
OneCharlieTango said:
A very large fraction of fuel is burned by those that require 100LL. Some say 80%, but I don't know where that came from.
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That is a figure that many people quote, but nobody can really back it up.

My thought is that it is just taking an almost universal idea. 80% from 20% is a rule of thumb applied to almost everything.
80% of the work is often attributed to 20% of the employees.
80% of the revenue is collected from 20% of the customers.
80% of the water is consumed by 20% of the users.

People apply the 80/20 rule to almost anything they can to prove their point. And in some cases,it is actually close.
 
JOhnH said:
That is a figure that many people quote, but nobody can really back it up.

My thought is that it is just taking an almost universal idea. 80% from 20% is a rule of thumb applied to almost everything.
80% of the work is often attributed to 20% of the employees.
80% of the revenue is collected from 20% of the customers.
80% of the water is consumed by 20% of the users.

People apply the 80/20 rule to almost anything they can to prove their point. And in some cases,it is actually close.
Click to expand...
As AV8R addressed in a previous post, that 80/20 is an old stat. The radials are gone from commercial service. The twins with big bore turbocharged engines have seen their utilization drop with the growth of the turbine segment. I doubt 80/20 is close any longer and if so, only because there is no 91-94 octane unleaded avfuel available, so your 172's and Cherokees default to 100LL. A good pull of ADSB data would serve as a baseline for usage by aircraft type, engine, fuel burn, and fuel type needed. The bigger stuff would be over represented because all those twins and turbocharged singles already have ADSB and there is a decent portion of the light fleet that doesn't have ADSB, so there would need to be some correction for that.

I wonder if there is an angle to use the current administration's nonchalance on environmental issues to have this can kicked again...
 
kyleb said:
I wonder if there is an angle to use the current administration's nonchalance on environmental issues to have this can kicked again...
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The can-kicking can continue only as long as TEL production continues. Since that's not subject to domestic fiats and the UK company has apparently indicated they intend to stop production in 2030, I think this transition is going to happen very slowly and then all at once.
 
AvNavCom said:
The can-kicking can continue only as long as TEL production continues. Since that's not subject to domestic fiats and the UK company has apparently indicated they intend to stop production in 2030, I think this transition is going to happen very slowly and then all at once.
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I bet it will be available from someone as long as there is a significant market for it. The Brit’s would probably extend their horizon if ours was pushed out. Most businesses like to operate their assets as long as possible.
 
kyleb said:
As AV8R addressed in a previous post, that 80/20 is an old stat
Click to expand...
Until I see where someone actually had some data and did the math, I still believe it is just a generalization using the 80/20 generalization. But it has been bandied about so much people tend to accept it as fact.

As the meme says: "Prove me wrong". (I won't mind,honest).
 
I'm not aware of anything that actually prohibits the manufacture of leaded avgas in 2030. The supply of TEL is very likely to be the determining factor in the near term.
Production of that chemical involves some very corrosive processes requiring expensive maintenance. Innospec has reported that they are not planning for TEL production after 2030. They are probably committed at this point to shutdown, even if only temporarily. TEL is only one of many products they make.

When I was learning to fly in the '70s, lots of general aviation airports had two fuels, 80 and 100. As demand decreased, we were left with the single 100LL option. It's revealing to see the list of planes on the Swift Fuels website that can use UL94. Pretty much any parallel valve Lycoming is covered. Sadly, that fuel is not widely available, and will be discontinued if their 100R fuel marketed. Testing continues. Interesting times indeed.
 
kyleb said:
The radials are gone from commercial service.
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There are still radials in commercial service though out the world but in specific markets. For example, Everts Air in AK. And in some cases those radials ops have no modern replacement airframes that can perform the same job. However, the biggest impact will be at the museum level that operate flying aircraft which require 100LL. Talking to a friend in the UK, its a point of concern with those that still operate those type aircraft.
 
737steve said:
I've been keeping up with this topic for quite a while now. I think it's reasonable to conclude that if there was a good solution, it would have been adopted by now. None of the four companies who have attempted to produce a "drop-in" replacement have succeeded in mass-marketing a product. Here's my guess as to how this will play out nearing 2030.

A more expensive fuel with somewhat less detonation resistance than 100LL will be grudgingly accepted. Some of the high-compression or turbocharged engines will face derating, and new performance charts. That will cost money, and require someone to do the work. Expensive, and potentially not worth the effort. There may be orphans. I think that water or methanol injection systems are not feasible.

What amazes me is the head-in-the-sand attitude manufacturers are taking with this looming deadline. Cirrus continues to churn out planes that need a fuel that will be unavailable shortly, simultaneously warning pilots about alternative fuels. Brilliant.

The vast majority of the world does not care if a big chunk of the piston fleet is grounded. How many politicians are going to lose their seats when the one remaining tetraethyl lead plant shuts down without a substitute? We all know the answer to that. It's unfortunate that this situation even exists give our level of technical expertise, but if I had a plane that really required 100 octane fuel, I'd be trying to sell it....soon.
Click to expand...
The airplane manufacturers need an engine to supply the demand for their airplane. What certified engine more than 300hp would you recommend cirrus install?
 
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