redbaron1982

Are these the stains you cannot remove with polishing?

I'm not sure how the supply chain works with GA avgas, but I'm quite sure that most, as in 99.9% of airports, don't have the infrastructure to dispense two different fuel types. So the key would be to have multiple formulations that can be mixed together so airports can switch from one to the other without major issues. I don´t know how this works with 100LL, is there a free (as in beer) spec that any fuel manufacturer can follow? Or each fuel manufacturer have their own proprietary formulation that meets certain specs?

Yeah, right, I also read that GAMI recommends G100UL right before a paint job, as it is going to give you a head start on stripping the paint. I can´t find now the link to that...

Can you provide the link to such information?

It looks like GAMI is acknowledging now that nitrile o-ring may swell if soaked in G100UL. https://www.avweb.com/aviation-news/gami-says-all-high-aromatic-gasolines-are-hard-on-paint/

How do you know they haven´t changed o-rings?

And I want to reiterate: there is no chance, not in a million years, that GAMI was not aware of this. They have been experimenting with this stuff for more than 10 years, I'm sure they have all the information, but they decide which to share and which to keep for themselves.

enough for G100UL not to be a drop-in replacement. If (that's a big if) the FAA is responsible enough, they should amend the STC to indicate that it requires replacing all nitrile o-rings before using G100UL and generate an AD for all aircraft that already have the STC.

https://www.avweb.com/aviation-news/california-mechanics-tests-show-g100ul-paint-nitrile-o-ring-damage-under-some-circumstances/ What a hot mess! I'm sure George will come up with some justification for this, such as unusually high solar activity or improper fuel dispensing techniques that resulted in an abnormally high concentration of some paint stripper.

Yeah, amazing right? I am sure it's all part of the same conspiracy that sells paint stripper in plastic containers.

There is absolutely no chance that GAMI was not aware of this. They have been working with this nasty stuff for more than a decade. It makes sense now why they insisted so much with "fueling hygiene". Maybe they were dreaming about everyone following their procedures without error and that all airplanes would have perfectly sealed tanks and no one would notice this.

I'm from Argentina too (I assume you're!), that's a fantastic trip! Looking forward to a PIREP! A friend recently flew from Houston to Sanfer in a Cessna 210T, but he went down through the Pacific coast, which is not a good option for us with NA engines.

well, yeah, I was thinking of 100LL staining that can be easily removed, and worst case some polishing would fix it.

More over, I would differentiate staining from stripping. Paint staining is not that "bad", and most likely can be corrected with some polishing. The pictures that @gabez looked more stripped paint.

I have a dual mag that was IRAN around 70 hours ago by Kelly, I have had no problem so far, but my understanding is that Kelly is one of the shops to avoid. I had some ignition issues around 20 hours ago and Savvy recommended sending the mags over to http://aeroacc-vny.com/ and they were amazing, they test bench the mags, and everything checked out so they returned them without charging anything but the shipping. Just for the service and transparency, I will send them over to Aero Accessories at Van Nuys if I ever have to do any work on the mags.

I'm not questioning if the STC route is correct or not, I have no idea which other routes exists either. What I'm saying is that only a small percentage of piston engines airplanes can legally use G100UL. If a state or the federal government bans 100LL with the current state of things they would be forcing the whole fleet to pay Mr George for the STC and then on top of that grant monopoly over the fuel supply. It's hard for me to see how that could be ok. I think the STC shouldn't be required or it should be free, and also wait for at least two alternatives (G100UL and Swift?) before baning 100LL.

Most of legal and regulatory stuff are distinctions without differences...

I'm quite sure that these statements are false. The correct statement would be "100% of all airplanes that use spark ignition piston engines can be modified through an STC to use G100UL". Technically only a small amount of airplanes are approved to use G100UL, only those with the STC.

As long as we are not forced to use paint stripper as fuel ...

All this sounds like a communist country (or at least state). Forcing a market to switch to a monopoly is the perfect recipe for corruption, abuse, and kill competition. Lucky for us, it looks like Swift 100R might be relatively close (2025?) to be an alternative, with ASTM cert. Maybe G100UL is just a bleep in the transition to unleaded fuel.

As long as your fuel tanks were recently sealed and the paint is brand new, it seems. G100UL doesn't seem to behave well with old seals and paint, which otherwise are fine with 100LL.

By the way, Swift was already aware of the issues that G100UL generates with paints and coatings: Does Swift Fuels allow G100UL to be mixed with Swift Fuels UL94 or 100R in an approved piston aircraft? No. G100UL must not be used at this time in aircraft approved for a Swift Fuels STC, and furthermore G100UL must not be intermixed with any Swift Fuels’ avgas product in any aircraft. This is because G100UL contains an aromatic amine “meta-toluidine” – an aggressive solvent that smells like turpentine – that testing shows is particularly prone to damaging paint/coatings, sealants, bladders, diaphragms, and various elastomeric parts in aircraft fuels systems.

That's assuming that the government does not ban the competition (in this case, 100LL), which in commie Kalifornia is already happening. There is no free market if the government intervenes to limit competition or favor one alternative.

I feel sorry for the pilot, you can hear him saying "it was my mistake" or something like that right after crashing. This would have been sooo preventable, just extending downwind a little bit or, in short final, just going around and landing 2 minutes later. I'm sure the guy got scared, thought he had an emergency and had to land as soon as possible.

And we are back online! It looks like George is not so friendly with Mooney's design over on AvWeb. Anyway, my take is this: who is the new kid on the block? Is it the Mooney wet-wing design or is it G100UL? If Mooney wings start leaking more fuel than before, it's not its design, but due to the new G100UL. Doesn't mean that G100UL is useless or should be banned... it is just different than 100LL and it's better in some ways (more oil life) and worse in others (tanks leaking more than they used to).