wombat

No they cannot. Any more than some A&P wandering around the airport can just randomly 'ground' planes they see as they are walking down the line.

I think maybe it depends more on what instruments you'll have fail if a power generation/transmission system like vacuum or electrical fails. If my vacuum system fails in IMC it's not a big deal.... I'll lose my speed brakes. I don't have a second alternator, if my alternator fails I'm operating on battery (Ship battery plus G5 independent battery) only for avionics so I've got a very limited time to get to VMC. Would I rather have electric speed brakes and a second alternator? Yup! Anyone want to fund it for me?

Some engines you can look at the cams by pulling the valves. Or draining the oil and sticking a borescope up into the pan from the bottom maybe? While I am normally of the attitude of "If you are selling your plane it's almost not even yours already so as long as the potential buyer hires a licensed A&P to do the work, let them do whatever they want"... But pulling a cylinder.... Maybe have a $5k non-refundable portion of the deposit for that. It's a little risky, even for a good A&P. Not very, but a little....

I don't think this was for me, but I've got < 10 hours at or above FL210 as well. Probably more than 8, but for sure less than 15. Regardless, it's REALLY few hours up there. It's really only useful for me when flying East because the altitude benefit is canceled out by the winds aloft when going west.

It goes on the "When I feel like it" schedule. hahaha If I was generating ice shortly before landing I'd probably do it a bunch more, but in cruise it's just 'for fun' and to see how well it works. It's not like I really need great visibility in IMC or when I'm going in and out of IMC.

Non-FIKI TKS. In about 2 minutes of a 4 hour leg on a 9.9 hour day. The ice in my hand was from the fairing between the fuselage and right wing. https://www.youtube.com/watch?v=A1i5kdDrvD4 (Side) https://www.youtube.com/watch?v=axZ6b8wKa0g (Front)

@Andy95W Ahh, thanks. That phrase isn't specifying "any 100 octane or 130 octane" aviation gasoline, it's the name of a specific fuel. I didn't know that.

@George Braly I appreciate that you are taking people's concerns seriously and are trying to recreate the conditions where the paint was swelling/softening/stripping. Do you have any thoughts on what could be different in the tests you ran from the examples we've seen where people had paint issues? I expect you are a busy guy but this seems to be a big enough deal with enough visibility in the 100 avgas burning community that it might be worth investing in getting an expedited answer. I think I wrote down some ideas in this or another thread, but the ones I still think of as reasonable are: The fuel that they used differs from the fuel you are testing with. Not making any statements on if the fuel they are using conforms to your specifications or why the fuel they are using might differ from the fuel you are using. Although I will say at a minimum I have to assume that the fuel you are using conforms to the G100UL specification. The paint on their samples differs from the paint on your samples in a meaningful way. (Different composition or type?) The tests are meaningfully different in that yours has a larger base quantity of fuel so the concentration of the 'substance X' that damages paint didn't get as high as it did in the other cases. Of course there are many other reasons the results might differ such as deliberate misconduct by people reporting results or other unknown factors such as trace air quality factors having an outsize impact.

Regarding the type certificate..... Is G100UL a 100 octane aviation gasoline? If my type certificate says I can use 100 octane aviation gasoline.... Umm... Maybe I missed that someone already brought this up....but it sounds like using G100UL doesn't violate any operating limitations.

Probably not. On the other hand, I would have expected Big Oil to have done significantly more testing and be less open about what testing they did.

My take-away from all of this is: #1: Based on the independent testing shown in this video: https://youtu.be/sPeQ6T3vB2E the negative effects that the OP @gabez and @larryb are probably caused by the G100UL they used. No testing was done to determine if this fuel was contaminated or if it met the manufacturer's specifications. #2: There are a lot of people that have very strong opinions about how much testing should be done prior to both making a new product available for use and making a new product a defacto requirement (such as prohibiting other options). #3: There are a lot of people that have very strong opinions about how bad the TEL from avgas is for people in the quantities and concentrations created by piston GA use. Personally, I'm disappointed that @George Braly's product seems to have this side effect and would love to hear back from him about this. This makes me less excited about the fuel, but I would still be willing to use it. I'm much happier knowing about the negative aspects than being unaware of them. This not disappointment in George or in GAMI; I don't have any evidence to indicate anything other than someone trying their best to bring a product to market legally and safely.

I somewhat disagree with you on this. Just because a new product has some flaws that old products didn't or performs more poorly than an old product did in some aspect that doesn't mean the new product isn't better or isn't worth switching to. If sealants last 99.5% as long with G100UL as they did with 100LL, that's probably a worthwhile trade-off. (average of 58 days shorter life span of 30 years) If it's 10% as long as with 100UL, it's probably not worth it. Now I'd love new products that have no regressions whatsoever but that's rarely the case.

My wife flies on the airlines fairly often. She always grabs a couple of sic sacks and puts them in the Mooney. *sigh*. Unfortunately that's actually true so I usually have to clear out a dozen or so from my plane once or twice a year.

Not grass, but I fly my turbo Mooney out of a 2,700' runway at 1,600 MSL. It's totally acceptable although during the summer I will not plan any flights departing in the afternoon unless the plane is very light.

Thank you. We need more people like you who are not out to recover every loss. If the shop was to deliberately fail to do the work that would be one thing but a good faith effort is all we usually pay for and good faith efforts are not guarantees that nothing will go wrong. This is how I operate too.

I agree and commend you for being extremely professional about how you are dealing with this. In my opinion, I think that everybody on this thread and the other has been really grown-up about this.

I think we have data to conclude with some reasonable degree of certainty that the new fuel does not adversely affect sealants at the very least. While @George Braly certainly does have incentives to show his fuel in the best light, he has described and shown data from testing on several sealant samples. While there is always room for more testing I think what he's done provides a reasonable degree of certainty on the sealants. While it is possible that his results are not representative of the fleet through either his deliberate influence or chance, I have a really hard time thinking it would be deliberate. More likely in my opinion is that a number of fuel tanks are sealed with inappropriate materials installed by 'hangar gnomes' because that was cheap and quick and seemed to work. Although what materials G100UL could degrade in a week that 100UL wouldn't degrade after months or years would seem to me to be a very small list. It could be that similar testing has been done for paints and I'm just not aware of it. I'll also restate something I said in another thread: If we were switching the other way (From G100UL to 100LL) and even not counting the health effects of the TEL, the entire community would be against the switch. I don't believe that G100UL is a flawless product, but I do believe that it's better than the one we have now. And while pointing out any flaws that G100UL might have is potentially good because this might lead to a 'fix' for them, preventing adoption until all possible flaws are fixed is not good in my opinion.

Between @larryband the OP @gabez we have two people that claim that within a week of adding G100UL to their tank they've had paint peeling. A couple of ideas on what could be happening: Coincidence that these things just happened to occur shortly after a fuel switch but are unrelated. The fuel as designed has a problem. The fuel has been contaminated either inadvertently or intentionally. The reporters are not being truthful about the situation. (I'm not saying it's likely or intentional but the list is incomplete if we don't include it) The ones I think we can maybe test for are #2 and #3. Could we get @George Braly some samples of the fuel from both the aircraft tanks as well as the fuel station, some of the 'stripped' paint, and maybe some paint chips or chunks that have not yet been softened?

That's too bad. Additional hurdles to compliance will result in lower compliance. That will result in increased risk.

I have the aftermarket Monroy tanks and I did a pretty good calibration on my 231 earlier this year on one of the tanks. You can see the details I recorded here: https://docs.google.com/spreadsheets/d/1eCCiLBGDNsSlQaziJ_DnWsNmMHbi8wbwifmRALW9uVo/edit?usp=sharing The sight gauge is accurate for the first 20 gallons but then it starts showing low because of the fuel in the aux tanks. Their highest marked measurement is 30 gallons I think but the needle continues moving for quite a while further. I estimated a '37 gallons' position' because that's as far as it moves. The gauge stops moving above about 45 gallons and I can fit more than 52.5 gallons in. I suppose it would be possible to re-mark the sight gauges with the top measurement at 45 gallons but that's WAY too much work.

Project Farm did a comparison test of several ceramic coatings:

99% joking here, but 1% honest... as a business minded person you should not own a GA plane. The number of times when it makes financial sense are so small that you shouldn't even try. I recommend like the others have said that you buy the plane you want with the most equipment you want that you can afford already installed and even with a timed out engine. Then you just fly it until you find some reason why you have to overhaul it. The longer the plane is down in maintenance for the engine overhaul, the better a deal it is for you because you won't be flying it and throwing money away! hahaha

@StParkin I've been flying out of the Puget Sound area for about 15 years now. If you want to fly in the winter, TKS (Preferably FIKI) is probably the most important factor. The next is having a turbo. Having both is the bee's knees. But even if you don't have them you can still fly a lot in the winter through careful flight planning and some schedule flexibility. If you have a TKS but not a turbo you'll still have good enough performance in the winter due to cold temps and can make it over the mountains more easily. Then in the summer you can fly VFR and your lower performance will still get you where you want to go since you are not as limited on routes and altitudes. As far as the Rockies go, by the time you get to them you'll have had plenty of time to climb to altitude, even at an extremely low climb rate. You will be able to get to 15,000+ and while there are probably some mountains you won't want to go directly over you can pretty much pick any route you want.

Between the TKS and old airframe and paint, I don't think I can quite make that. I did it once, but I had tailwinds that were closer to 75KT. We could have our LOP discussion here, but so far I have not been able to make it run LOP without stumbling occasionally. Unfortunately I've been too focused on making the individual flights get from A to B to spend much time actually playing around with it.

@bloghill Welcome to the Rocket club!! I've had mine for about 1.5 years and 200 hours and love it. @201Steve I tend to get about 190KTAS on mine. I usually fly at the 72% 'Normal Cruise' power setting, I expect the seller was at the 65% 'Economy Cruise' power setting based on his fuel flow statement. While we can fly faster, the fuel consumption is a lot higher. Much of the time I am either going to Seattle and back, which is relatively short (< 1 hour) and is mostly in the climb or descent so a higher cruise power setting won't make much difference. Or I'm on a much longer XC (2S0 <-> KFFL) where I'm fuel limited and I usually then finesse the fuel flow and power settings to get the range & reserve I want.