redbaron1982

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).

The engine was producing power, for sure. After landing you can see the RPMs at a steady 800. There is no way the prop would windmill at 800 RPMs while taxing at 30kt

This is a shit show... like everything around ____UL (as in anything unleaded fuel related)

Reading this, I understand that there is some agreement that switching to G100UL could generate issues like the ones reported here. This statement says, "Hey, the same happened when we switched to 100LL". Acknowledging that switching from 100LL to G100UL could make worse some already bad conditions of seals/paint, especially in wet-wing airplanes, would be a good starting point.

The main thing I dislike about GAMI/George is that they always talk from this perspective: "We know everything; everyone else that doesn't say the same thing we do is wrong." Not pursuing ASTM is one example of such an attitude; not investigating the issues starting to arise is another. They keep repeating the tests they did in the lab about paint and disregard what people are complaining about. I value all the effort, investment, and time they put into this. And I believe we will have many benefits from switching to UL, not only environmental but maintenance as well.

That makes sense. I'm going to take a look the next time I remove the cowling, I don't recall seeing one in my Mooney, but I haven't look for it either.

I always use the tube on the front wheel where the tow bar goes. I'm quite confident that it has continuity with the airframe. I do see how the exhaust could not be a good idea. It's bolted to the engine, but then the engine has the mounting bushings that are rubber... and the whole engine has no continuity with the airframe, no?

Agreed 100%. I'm not sure how many shot fields there are where you can (and/or would be smart to) shoot an ILS down to minimums.

Do you know who is my instructor? I can't think of another way you made that statement...

Not good

Do you guys use full flap when landing on IMC? My CFI used to suggest approaching with landing flaps instead of full.

The GAMI article is not clear, as it mentions staining, and it compares it with the blue stains you can get from 100LL. But it does look like GAMI knows more about what they are sharing, and the staining could be paint damage. 100LL seems to be 100% safe on paint. I have a very small leak on the LH sump for years, it is not dripping or anything, it is just staining. A couple of weeks ago I decided to see if I could clean it up, and all the staining was easily removed, leaving the paint in perfect conditions.

Is there any evidence of this or is it just suppositions?

I know many will have a lot to say, but it sounds fishy that after so many years of testing, one person has all this damage in just one week.

Is this the first time with a constant-speed prop airplane? If so, the manifold pressure in a NA (normally aspirated) engine can never be higher than the atmospheric pressure at the altitude the airplane is flying. So, on a standard day (ISA 15C 29.92inHG), if WOT (wide open throttle), you would get ~29.9 at sea level, and drop 1" every 1000ft of altitude. So, lets say you are flying at a density altitude of 11kft, then, WOT, you won't have more than ~30-11=19inHg.

Lycoming filler neck removal tool should be called! My experience is that if the dipstick is too tight, you will also unscrew the filler neck when removing it.