Another reason not to run G100UL…

Racerx said:
Didn't know gami gas was blue
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That’s from the old bladder that just got replaced. Also has to run 100LL when filling up away from home. You can see the greenish staining around the leak
 
Theres plenty of videos and forum posts showing that G100UL isn't as great as the company says it is. It seems to wreak havoc not just on paint but also on O-rings. I'm not surprised to see it is possibly causing bladders to leak. I wish it would work as advertised, but at this moment, I don't trust it enough to put in my plane. AOPA recently filed a suit against a couple California airports for restricting the sale of 100LL.
 
It would be really cool if someone who has access to G100UL and some old o-rings/bladders and painted parts to soak in it would do some tests and post the results. I would but I don't know where I'd get the former and I don't really have much in terms of the latter.

It would seem easy enough to just get some jars or something with G100UL and put these different parts in them for a period of time and document what happens.
 
cowman said:
It would be really cool if someone who has access to G100UL and some old o-rings/bladders and painted parts to soak in it would do some tests and post the results. I would but I don't know where I'd get the former and I don't really have much in terms of the latter.

It would seem easy enough to just get some jars or something with G100UL and put these different parts in them for a period of time and document what happens.
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Fascinating. Thanks @Will Kumley

Food for thought: if something as obvious as paint and orings are observed to act differently than what was initially stated by GAMI, then what about statements regarding engine performance and longevity?

I’ll be the last to adopt, I always am. Case in point was my updating the Avidyne firmware when 10.3.x came out - I didn’t do for a couple years.

I wanna keep my money in my wallet and my blood on the inside.
 
455 Bravo Uniform said:
Fascinating. Thanks @Will Kumley

Food for thought: if something as obvious as paint and orings are observed to act differently than what was initially stated by GAMI, then what about statements regarding engine performance and longevity?

I’ll be the last to adopt, I always am. Case in point was my updating the Avidyne firmware when 10.3.x came out - I didn’t do for a couple years.

I wanna keep my money in my wallet and my blood on the inside.
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Luckily I think us Midwesterners will be the last to adopt. California can be the beta testers.

What's interesting is the AOPA Baron had original bladders that began to leak. Yet they apparently didn't have paint issues.
 
Paint comes in many flavors. I don’t know how many variations certified airplanes are painted in, but it doesn’t stretch my belief to think that a single solvent could dissolve one type of paint and bead off another. I do have an old fuel bladder in a box that I don’t know what to do with, so if I happen upon some G100UL and free time I could work up an experiment.
 
My home field KWVI Watsonville has several horror stories like @ktup-flyer

Fuel sales are a just a trickle and the airport wants it pumped out. The airport manager even raised the price of 100LL to within .25 cents of 100UL to make it price parity. Following what has happened at KWVI and KRHV Piper, Textron, Cirrus, and Lycoming have all published letters stating they will (not) pay warranty claims resulting from 100UL usage.
 
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If G100UL is so bad, why hasn't the FAA suspended or cancelled the STC? Or is it just too soon and they are collecting data...?
 
NordicDave said:
. The airport manager even raised the price of 100LL to within .25 cents of 100UL to make it price parity. Following what has happened at KWVI and KRHV Piper, Textron, Cirrus, and Lycoming have all published letters stating they will pay warranty claims resulting from 100UL usage.
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ND: not one to nitpick but has “not” (pay) been inadvertently dropped from this sentence?
seems important or I’d say nothing
 
My questions are this, with leadership change at the EPA how about the potential for 100LL to stay around longer?

Another silly question, I thought aviation fuel wasn’t really low in lead. Is there a way they could just reduce the lead more, make it, ELL, ‘even lower lead’. I guess the lead helps with octane, maybe reduce that down some, still workable at 96 or whatever.

I still say, the handful of planes flying around burning 100LL has to have minimal effect on any lead dispersal. Just trying to get some thought outside the bun, likely already considered.
 
sourdough44 said:
My questions are this, with leadership change at the EPA how about the potential for 100LL to stay around longer?

Another silly question, I thought aviation fuel wasn’t really low in lead. Is there a way they could just reduce the lead more, make it, ELL, ‘even lower lead’. I guess the lead helps with octane, maybe reduce that down some, still workable at 96 or whatever.

I still say, the handful of planes flying around burning 100LL has to have minimal effect on any lead dispersal. Just trying to get some thought outside the bun, likely already considered.
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I suspect 100LL will stay around as long as TEL remains in production. But then what?
 
sourdough44 said:
My questions are this, with leadership change at the EPA how about the potential for 100LL to stay around longer?

Another silly question, I thought aviation fuel wasn’t really low in lead. Is there a way they could just reduce the lead more, make it, ELL, ‘even lower lead’. I guess the lead helps with octane, maybe reduce that down some, still workable at 96 or whatever.

I still say, the handful of planes flying around burning 100LL has to have minimal effect on any lead dispersal. Just trying to get some thought outside the bun, likely already considered.
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Doubtful EPA leadership has any effect. The timeline and movement forward are largely the result of court settlements because EPA was failing to follow laws passed in the in 1970s.
There is a standard called 100VLL, as in very low lead. 100LL allows for a fairly wide range of TEL additive, but does require some TEL. The VLL just restricts the adding larger quantities, so fuel which meets 100VLL spec will also meet the 100LL spec. No idea on the numbers, but from what was posted by some guy on the net, a significant portion of 100LL actually meets the 100VLL spec.

As for lowering the octane, the short answer is no. The planes which consume the most avgas, are the planes which require the 100 octane rating. If the FAA wanted to go this route, they should have done so in 1970 when the EPA began the phase out of TEL in auto fuels with new cars starting with the 1975 model year.

Tim
 
JOhnH said:
I suspect 100LL will stay around as long as TEL remains in production. But then what?
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That’s the existential question because it forces hands to be played; unfortunately the FAA and legacy engine OEMs can just hold or fold as desired while Rotax and other options will just carry on.

Since SEP accounts for ~90% of the 220,000 GA airframes (AOPA’s stat), I guess hangar space might get easier to come by.
 
This also feels a bit like a self-licking ice cream cone. So long as aircraft manufacturers are still producing aircraft that need 100LL, there will always be a driver for 100LL production. And so long as 100LL is in production there’s little incentive to really push for modern engine technology in piston aircraft.

Yeah, I understand the challenge of getting a new certified engine out there (which Rotax has successfully done) but, in the ‘70’s, the idea of dramatically cutting smog while dramatically increasing fuel economy was also daunting - and, like them or not, environmental regs drove the change. And I personally think the outcome is way better than the status quo in the ‘70’s.

If it were decided no new engines requiring anything other than Premium mogas could be installed in new aircraft after a date, there would be change. And there would possibly even be better retrofit options for legacy aircraft.

That said, the market is so small that it would likely kill off many current aircraft manufacturers.
 
Every time I saw George Braly make a speech, he came across as an angry man whining. He wanted to rush into production and a lot of people defended him and said he was being treated unfairly.

None of the four potential suppliers wanted to work together. FAA said they don't just have to test their own product, but a mix of their product, 100LL, and any other fuel that is approved in different percentages. George felt like this was unfair. In his mind, he assumes he gets 100% of fuel sales, therefore there's no reason to assume there will be other products to mix with, except for 100LL.

A Texas airport started selling G100UL, and got defensive when people said it's not safe. They said they have over a dozen planes using it with no issues, but couldn't answer how many hours those planes had flown on G100UL and how many of them were using a mix of G100UL and 100LL

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Lowflynjack said:
Every time I saw George Braly make a speech, he came across as an angry man whining. He wanted to rush into production and a lot of people defended him and said he was being treated unfairly.

None of the four potential suppliers wanted to work together. FAA said they don't just have to test their own product, but a mix of their product, 100LL, and any other fuel that is approved in different percentages. George felt like this was unfair. In his mind, he assumes he gets 100% of fuel sales, therefore there's no reason to assume there will be other products to mix with, except for 100LL.

A Texas airport started selling G100UL, and got defensive when people said it's not safe. They said they have over a dozen planes using it with no issues, but couldn't answer how many hours those planes had flown on G100UL and how many of them were using a mix of G100UL and 100LL

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That last comment looks like it was written by ai. Or by someone who knows absolutely nothing about aviation. Actually, all of the comments by Refugio read that way.
 
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I've been skeptical that 100LL is going away from the start and I still am, but...

It would seem like the hose and o-ring issue is not that hard to solve- unless I'm misunderstanding we do have compatible materials. So, unless I'm mistaken isn't that something that can be fixed with off the shelf generic replacement parts and a day or two of shop labor or less depending on the aircraft type? Then we'd just need to figure out a compatible material for fuel bladders/sealant for wet wings right?

Another annoyance/expense for aircraft owners but one that doesn't seem to me like that far out of bounds beyond what we normally deal with anyway. The FAA can just issue an AD and we can take care of that stuff I would think.

I'm more concerned about the reports of valve recession, if that turns out to be legit and it's not something that can easily be avoided by changing engine management techniques I think that's what would sink G100UL.
 
cowman said:
I've been skeptical that 100LL is going away from the start and I still am, but...

It would seem like the hose and o-ring issue is not that hard to solve- unless I'm misunderstanding we do have compatible materials. So, unless I'm mistaken isn't that something that can be fixed with off the shelf generic replacement parts and a day or two of shop labor or less depending on the aircraft type? Then we'd just need to figure out a compatible material for fuel bladders/sealant for wet wings right?

Another annoyance/expense for aircraft owners but one that doesn't seem to me like that far out of bounds beyond what we normally deal with anyway. The FAA can just issue an AD and we can take care of that stuff I would think.

I'm more concerned about the reports of valve recession, if that turns out to be legit and it's not something that can easily be avoided by changing engine management techniques I think that's what would sink G100UL.
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I mean, I get what you're saying about upgrading hoses and seals. But a fuel leak that strips the paint is pretty damning.

I haven't seen anything about valve recession for g100ul. Id be surprised if anyone had the number of hours with the fuel to cause that. We have seen it with swifts 94UL, which may actually not be 94 octane
 
Llewtrah381 said:
This also feels a bit like a self-licking ice cream cone. So long as aircraft manufacturers are still producing aircraft that need 100LL, there will always be a driver for 100LL production. And so long as 100LL is in production there’s little incentive to really push for modern engine technology in piston aircraft.
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If it was up to the FAA, oil companies, and pilots, 100LL would be available forever.

But you have the Karens riled up and worried about their kids.

And add in that there is ONE company making TEL.

100LL could go away in a couple of years. And then where would we be??
 
Racerx said:
I mean, I get what you're saying about upgrading hoses and seals. But a fuel leak that strips the paint is pretty damning.

I haven't seen anything about valve recession for g100ul. Id be surprised if anyone had the number of hours with the fuel to cause that. We have seen it with swifts 94UL, which may actually not be 94 octane
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I might be wrong on the valve recession, could have sworn I heard something about it but maybe it was just speculation based on the 94UL issues.

As for the paint issue- is it possible simply using a different paint would fix it? If nothing else just adjusting our fueling procedures and being more sensitive to seeps/leaks might make things viable. I'm not enthusiastic about any of this and I'm content to keep using 100LL but should that turn out to not be possible, it's not a bad idea to have a plan B.
 
Pinecone said:
…
And add in that there is ONE company making TEL.

100LL could go away in a couple of years. And then where would we be??
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We’re one industrial accident or business decision on Innospec’s part from TEL not being available any longer.

Failing to acknowledge that prevents there from being a problem to begin with, and I fear most don’t acknowledge that fundamental truth.
 
Lowflynjack said:
Every time I saw George Braly make a speech, he came across as an angry man whining. He wanted to rush into production and a lot of people defended him and said he was being treated unfairly.

None of the four potential suppliers wanted to work together. FAA said they don't just have to test their own product, but a mix of their product, 100LL, and any other fuel that is approved in different percentages. George felt like this was unfair. In his mind, he assumes he gets 100% of fuel sales, therefore there's no reason to assume there will be other products to mix with, except for 100LL.

A Texas airport started selling G100UL, and got defensive when people said it's not safe. They said they have over a dozen planes using it with no issues, but couldn't answer how many hours those planes had flown on G100UL and how many of them were using a mix of G100UL and 100LL

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They’ve been trying to push it here, and even had a whole fly in for it, with fuel discounts up to the cost of the STC. Hardly anyone showed up and next to nobody buys it. Not worth the risk.

IMG_2220.jpeg
 
TCABM said:
We’re one industrial accident or business decision on Innospec’s part from TEL not being available any longer.

Failing to acknowledge that prevents there from being a problem to begin with, and I fear most don’t acknowledge that fundamental truth.
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I think we all know this. The issue seems to be that the GAMI solution isn't a solution - well unless you're looking for a way to eat through bladders and paint. But the pro GAMI/Anti-100LL people seem to be saying "you don't need paint or fuel bladders and o rings! Just strip all the paint from your plane, and install some magical steel bladder and o rings in every airplane."

What I want presented as a legit solution:
About the same price as 100LL currently is/would be.​
Can be used from -60C to +50C and from -2000MSL to FL300​
Is a legit drop in for 100LL in ALL engines/aircraft.​
(I don't care that you fly a Cub and can burn 87 E15 from the Marathon at the corner.)​
Doesn't eat paint and dissolve bladders.​
Isn't reliant upon one single source to bring the non-kerosene sector to a halt if there's an issue.​
​

​
 
I would absolutely love to see lead gone. It’s a pain - it fouls plugs, causes short oil change intervals and keeps us from using 100% synthetic, and messes up our planes’ bellies. But for now, it seems to be the only practical way to raise octane. Infinitely more important than reducing lead usage is not causing airframe and fuel system damage.
 
EdFred said:
I think we all know this. The issue seems to be that the GAMI solution isn't a solution - well unless you're looking for a way to eat through bladders and paint. But the pro GAMI/Anti-100LL people seem to be saying "you don't need paint or fuel bladders and o rings! Just strip all the paint from your plane, and install some magical steel bladder and o rings in every airplane."

What I want presented as a legit solution:
About the same price as 100LL currently is/would be.​
Can be used from -60C to +50C and from -2000MSL to FL300​
Is a legit drop in for 100LL in ALL engines/aircraft.​
(I don't care that you fly a Cub and can burn 87 E15 from the Marathon at the corner.)​
Doesn't eat paint and dissolve bladders.​
Isn't reliant upon one single source to bring the non-kerosene sector to a halt if there's an issue.​
​
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That list has been the target for fifty plus years. And you can see how much progress has been made.
The reality is something will have to give. From the outside viewpoint, George had one epiphany about replacing 100LL that FAA seems to have adopted in the switch from PAFI to EAGLE. No longer is it about matching the 100LL DTSM specification, but instead matching the performance criteria in the engines without requiring replacement of the engines.

The racing fuel company, I cannot spell the name correctly, has pretty much warned there will be material compatibility issues. I believe Swift has also.

Tim
 
Have there any reports of valve issues with aircraft engines run on Mogas? If no, then lead's main benefit in avgas is the anti-knock and octane boost properties?
 
tspear said:
The racing fuel company, I cannot spell the name correctly, has pretty much warned there will be material compatibility issues. I believe Swift has also.

Tim
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seems like that is unavoidable at this point. Hard to believe someone is going to find a magic lead replacement where the rest of the 100LL soup can remain the same.
 
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