donkaye

George, What polish did you use?

KRHV has a form that needs to be filled out before they will fill with G100UL. Either have the sticker on the wing or show your copy of the STC. I have it on my iPad, but haven't needed it because of the wing sticker.

I'm a proponent of G100UL. I'm on the side of the "Glass half full" rather than "Half empty" philosophy. I don't have the patience or the inclination to become an expert on fuels, as some on this forum. So, I'm with George on this. I believe in his research. Ironically, my Dad was a PHD chemist who specialized in rocket fuel research. However, just as your tongue is constantly attracted to a problem with a tooth, so am I every time I do a preflight and see the light staining on both side of my fuel tanks. It's annoying, so on Monday I'm going to call a top notch paint shop in Salinas and set up an appointment to see if they can buff it out, and if not, I think I'll have my wing repainted.

About 50%.

For numerous reasons I don't run my engine LOP. I tried for awhile many years ago, but after expensive exhaust repairs, the inability to get the TIT to behave in a reasonable manner, the lack of smoothness of the engine, and the fact that I didn't buy the airplane to go slow, I chose not to run it LOP. I've attached a LOP chart for the Bravo, however. LOPFFvsHP Bravo.xls

I've been using G100UL intermittently, since I'm not based at KRHV. I've experienced no operational change different from using 100LL other than the light staining I described earlier. I intend to closely watch fueling in the future and not allow any matt to be placed on the wing. As my plane has been hangared all its life, my paint is the original paint from Mooney. I had my tanks resealed by Weep no More in November of 2016. Since the plane is a 1991 model, that means 25 years to reseal.

I wasn't going to post to this thread anymore because of its negativity, but I've decided to post one more time. George, I wouldn't respond anymore to those who are sure you're in it only for the money and are out to try to cause G100UL to fail whether deliberately or other reasons. Having the determination to get FAA approval over a period of 12 years show an interest that's not only financial, but for the general betterment of General Aviation in my opinion. Without trying to be arrogant, i've seen this mentality before when I was an Electrical Engineer. I got interested in Real Estate and buying homes in particular. After a few years and seeing the benefits of buying rental homes, I suggested to others in my engineering circle that they should consider doing the same. The pushback was immense and I just stopped talking about it. Fast forward 50 years and everything I tried to relate to my cohorts have come true for me. I have no idea how my other engineering friends are handling their later years, but for me, I have been able to devote my time in service to others by flight instructing full time, and I have't had to work for anyone since 1974. While a real estate program from technical standpoint is not on the same level as bringing an aviation fuel to market, it does prove that it's not always wise to listen to the naysayers. Outside of the staining issue there may be other issues that develop over time. I'll deal with them as they may develop. Meanwhile, I won't shy away from using G100UL.

As I mentioned before, I fly airplanes, am not a mechanic, and for better or worse trust the people who designed them. I have no idea about the materials used in the fuel system. There are risks in life, and my love of flying means choosing an airplane I think minimizes that risk by a design that has stood the test of time. Mooney is that airplane.

The FAA provides approval of STCs. They provide approval for the certification of our airplanes. They took over 12 years to approve this STC. They are strict in their approval process. Every time I get in my airplane I am depending on the Avionics, the design details of which I am not familiar; the engine, the design details of which I am not familiar; the manufacturer of all the components, the designs of which I am not familiar; the fuel, the design of which I am not competent to render a judgement on. I am a pilot and I know how to fly an airplane. How an airplane is made and it components, while interesting, I leave to the experts. Based on past history, I am willing to trust the experts. Do I like that G100UL stains paint? No, but mitigation was described in the paperwork that came with the STC. I think the fuelers need better instructions including use of their wing "protector", that I think caused my issue. Do the people who have commented on these threads commit the time to investigate every component on their airplane? I think not. As an example, we trust our Avionics without question, don't ask to look into the software to see if we can find a problem. We blindly read the manuals and assume it will work as published. We use the avionics and from time to time find flaws in it. I have found and communicated flaws in the Aera 796 and 760, and even the G500TXi, for example. Garmin for the most part has fixed them. Avionics issues could harm us quicker (and has with failed vacuum pumps in the past) than this fuel issue being discussed ad nauseam. Much of what is being said, and my not being an A&P, is incomprehensible to me. Bottom line to me is if you want the benefits of unleaded fuel with some caveats use it, and if, not, don't. That being said, Happy New Year.

@redbaron1982 have you met and spoken with George Braly? Have you taken the Advanced Pilot Training Course? If not, then my recommendation is to cut down on the disparaging rhetoric. Talk like you have been rendering has lost this forum many valuable contributors. I would like to see things remain civil and continue to have experts like George remain here.

Based on the area disturbed, that probably wouldn't work for me.

In another post I mentioned the % G100UL to 100LL and the % was less than 50% on each case, so at this time there probably wouldn't be any significant change. I was looking forward to the real benefits of G100UL when it became so readily available that I would always have the choice to use it. With 100LL being used mostly in my plane borescoping it wouldn't be very valuable at this time. Knock on wood, there hasn't been so much as a hiccup in the engine and it runs smooth as silk for a Lycoming.

I usually use self serve and there is no protective matt for 100LL. I never noticed any staining before on the wing. 100LL stains blue and I have never had any issue removing it, but only occasionally does it overflow. I immediately wipe the wing when that happens. This color is the color of G100UL. As I mentioned in an earlier post, I still intend to use G100UL, but will use extreme care with it.

Yes. It wasn't possible with all the rubbing compounds I tried. I used 4 different plastic cleaners that I usually use to clean the lenses on the lights and one heavier Turtle Wax rubbing compound. I spent over an hour with the various products with very little improvement. I didn't want to go further for fear of making things worse.

I will not allow the fuelers to use the "protect matt" in the future. I think there was fuel underlying it. I will watch as they "carefully" insert the hose. For the record:

I bought G100UL 3 times since November 2, 2024 when I got the STC signed, balanced on both sides. That day I got 25 gallons free. I estimate I had 40 gallons prefueling. The 2nd time was November 8th and I bought 38.9 gallons. I topped it off so 50 gallons prefueling. Finally, I bought 21 gallons on December 19th and topped it off again in preparation for a long trip on the 23rd. So 68 gallons prefueling. So, approximate % G100UL total fuel after each refueling; Fuel 1: 25/65 = 38% ; Fuel 2: 38.9/89 = 44% ; Fuel: 3 21/89 = 24% The above is approximate for 2 and 3, since I don't know how much G100UL remained in the tank before refueling 2 and 3.

I've got over 20 hours on the mixture of 100LL and G100UL. There does appear to be some minor staining at the fuel openings as indicated previously. As to operations, it performs well. I will continue to use it, monitoring carefully fueling and inspect drains and vents more carefully. I choose to put more weight on the positives as opposed to the potential negatives at this time, but each to his own.

I can't emphasize enough about the care that's necessary to prevent staining. Although I've watched each filling and the men were very careful, I think there must have been some fuel on the bottom of the protector that they put over the gas entry point because I can't get some staining removed even after using every fine abrasive that I can find and spending several hours trying to remove it. I think I'll take my chances about being charged for dumping the fuel sample rather than trying to make sure every last drop is returned to the tank. For me the only negative about using this fuel so far. If the wing weren't white it probably wouldn't show.

It cannot be corrected with polishing.

I think the leaks and stain should be separate questions.

I love having the vernier throttle. Having had it for the 32 years I've owned my airplane and teaching over the past 30 years with so many airplanes that have it, I don't give it a second thought except to appreciate having it. I never have to worry about throttle movement if I take my hand off of it to fly a precise soft field takeoff. All the arguments above don't hold a bit of water for me. If you're not flying aerobics, there is no reason to have to "smash" the throttle full forward. The throttle can be "smoothly" increased with the palm of your hand on the "button" and your forefinger used on the throttle end to control the rate of throttle addition. On landing the proficient pilot never "cuts" the throttle. That will immediately unstabilize the approach. On a stabilized approach the throttle is rolled off at the same rate as the airplane is flared. Power is much more precisely adjusted with it than with the push/pull throttle. For formation flying my mechanic designed a cover for the throttle end that keeps the button "in" and allows push/pull operations.

The road and traffic going by KRHV is terrible now as the result of a new construction project bring apparently overhead rail to the South Bay. The project is massive and looks to continue for several years.

For an airport that is supposedly going away in a few years, a whole lot of money was just spent upgrading the runways.

I like the potential benefits of G100UL. I'll follow the fueling guidelines. I've read all the documentation that came with the STC and have listened to George Braly's comments both in person and online and find them compelling. My tanks were resealed by Paul at Weep no More in Willmar 8 years ago. I was impressed by their process. Notwithstanding some of the comments in this thread, I'll continue to use G100UL.

I checked back on my upgrade from the G500 to the G500TXi. I was charged 11 hours labor. There was also the charge for the new panel and power coating and painting it. Garmin gave an exchange discount of several thousand dollars if you sent your old G500 back to them. The Hardware net cost was $11,450. 11 hours at $80/hour (6 years ago when labor was cheaper) =$880. Since you don't have to have a new panel made, you don't have those costs.