I wish for a time of reason and a sense of proportion.
Unfortunately the powers that be are promoting irrational emergencies.
It may be best for these people to get together and NOT “do something”.
Fully understood. But nobody is suggesting that Avgas goes away when Mogas is added to the fuel options. Yes it will require an additional fuel system, but U-Fuel offers small turnkey, above-ground, self-service units for a modest sum.
To expand upon Yars reply - most of the GA fleet (about 70%) can burn mogas.
But those low-compression engines account for less than a third of fuel sales. Most avgas (also about 70%) is consumed by high-compression engines used in business/commercial operations. They consume more fuel per hour and fly many, many more hours. The aren’t flying patterns on the weekend when it “looks busy”. They’re somewhat invisible, flying hither and yon cross-country during the week when most of us ‘weekend warriors’ are at our day jobs. These planes can only run 100 octane fuel.
Mogas outsells avgas by roughly 1,000 to 1. With that kind of volume it’s easy to economically have multiple grades of gasoline. With mogas, most stations have only two flavors - high and low octane. All of the intermediate grades are just a mix of the two. About half or more also sell diesel fuel, primarily nearer interstate highways and other concentrations of diesel-power vehicles.
Avgas sales are so much lower, and their inspection requirements higher, that it’s usually not economical to split the pie into two smaller pieces. Doing so would double an airport’s storage and delivery costs, but would not double fuel sales.
Adding a mogas option would increase an airport’s costs, but wouldn’t increase fuel sales. It would just siphon off the 30% of low-compression fuel sales from the avgas pump.
Some pilots I know have tried running E0 mogas in their O-360 powered experimental aircraft and on hot days, the results have not been good. As in engine failure (fortunately over an airport) and not being able to start. As a result of these experiments, they have 100 LL in one tank and E0 in the other tank “just in case”.
This and other antidotes tells me one has to be very careful using E0 mogas in aircraft. Hopefully the GAMI and SWIFT fuels are better and not going to be priced over $10 / gallon.
Are GAMI and SWIFT fuels based on petroleum products in anyway? If any of the fuel components are derived from fossil fuels, the stated policy from the current government administration is to eliminate fossil fuels which means GAMI and SWIFT fuels would be a non starter. Perhaps the FAA is grappling this this issue.
What concerns me is when people with no idea what they are doing, as in legislators, get involved in trying to solve large, complex and complicated systems problems. The results are not good. Anyone try and order any parts lately?
Lots of issues with Mogas, mainly it is not stable and secondly how do you keep ethanol out of it. They can make 94 UL which is the avgas they make now without the lead. Not sure why that cannot happen. As others have said the major users of avfuel are the high compression engines that need the 100 and that is the problem that needs to be resolved.
Please define “engine failure”.
Was it:
- Failed to produce needed or expected power
Or - Blew up/Reduced to scrap metal.
There’s a difference.
My understanding is that G100UL is based on the same 94UL that 100LL is based on, but with different additives instead of TEL. I don’t know much about Swift, but I thought it was based on bio-renewables.
In any case, don’t confuse the growing movement of trying to eliminate ICE-powered consumer vehicles with eliminating fossil fuels altogether. That’s a significantly bigger and complicated issue, and I don’t see it likely affecting aviation for quite some time. Certainly well beyond 2030.
As for the “lead lubricates valve seats” theory - that was never true. Aluminum-cylinder heads have always used hardened valve seats. Not just in the past 30 years, but pretty much since the beginning. Aluminum is too soft for direct-machining valves seats like cast-iron heads.
Even so, lead never lubricated anything. The spate of valve-seat recession that occurred when unleaded fuel was introduced to cars in the 1970s was primarily because of lower octane. When lead was used to boost octane it was common to add a bit more just to make sure it met the posted octane amount. So what most people bought was usually a bit higher in octane.
But with unleaded fuel it was more difficult to meet the posted octane. As a result the gas dispensed was exactly the posted number, not a couple of points higher. As a result people were driving around on effectively lower octane than they were used to, resulting in more pinging, detonation… and valve recession.
Actually, G100UL is a different mix of existing chemicals. Instead of trying to find a new additive to replace lead like previous failed attempts, they found a new blend of hydrocarbons that has an inherently higher octane than the blend of chemicals in gasoline. This is why G100UL weighs more than 100LL (6.3lbs/gal versus 6.01 lbs/gal). But it also has slightly more energy per gallon (about 1-2%) so you can theoretically go a bit farther per gallon than 100LL.
While simultaneously reducing the overall range of your aircraft. 5% heaver, but 1.5% more energy dense is a net loser for range. It’s not a lot, but it’s there.
Hear hear!
The problem is finding non-alcohol contaminated mo-gas regardless of any available STCs. I had a low compression 0470 that would have been happy with mo-gas but it was simply not available or transport onto the airport was strictly prohibited
I wish for a time of reason and a sense of porportion.
This ain’t it.
The studies proved there was no problem of lead contamination around airport populations and showed the lead levels were the same throughout the state regardless of nearness to an airport. Simply ignorant, pandering political grandstanding.
And add it to the mogas pump. Net fuel sales will be the same or even increase as it is a pain to transfer fuel by car or truck to the airport.
They are already losing a significant portion of those sales completely. I run through about 1500 gallons of mogas a year, nearly all not bought at the FBO because they do not carry it and leaded fuel is a maintenance nightmare.
Most airports I visited with my low compression O-470-R had 80 and 100LL and a quite a few even had 100 Green when I first got my airplane in the mid 20th century.
When 80 disappeared, I switched to 100LL on a steady diet and ended up with a bottom spark plug fouling requiring cleaning every 10 hours no matter how lean I ran the airplane. I got the mogas STC, got a transfer tank and switched to lead free alcohol free fuel, ran nearly 1000 hours past TBO.
Airport FBOs had the facilities to carry at least three fuels (JetA, 80 and 100LL) for years. So what if it siphoned off 100LL fuel? They make the same or better markup per gallon on the fuel. The corner gas station sells 87, 91, 93, E15, E85 and alcohol free mogas as well as diesel. I’m pretty sure they make more money on the E0 as they charge a dollar or more a gallon more for it.
I ran into this problem at one airport which attempted to prohibit non-fbo fuel being brought onto the airport. This was contested and the airport lost. Please see FAA AC 150/5190-6 Exclusive Rights at Federally Obligated Airports Paragraph 4:" It is FAA policy that the sponsor of a federally obligated airport will not grant an exclusive right for the use of the airport to any person providing, or intending to provide, aeronautical services or commodities to the public and will not, either directly or indirectly, grant or permit any person, firm, or corporation, the exclusive right at the airport to conduct aeronautical activities. The exclusive rights prohibition applies to both commercial entities engaging in providing aeronautical services and individual aeronautical users of the airport. The intent of the prohibition on exclusive rights is to promote fair competition at federally obligated, public use airports for the benefit of aeronautical users. The exclusive rights prohibition remains in effect as long as the airport is operated as an airport, even if the original period for which an airport sponsor was obligated has expired."
Hot day? CHTs? Cowling/cooling air flow? Fuel lines plumbing/routing? Fuel system design? Similar failures with 100LL?
There have been many like tens of thousands of event free hours flown on mogas using both EAA and Petersen STCs. Anecdotes do not an exception make and correlation does not imply causation. A pilot I know had an E0 fueled loss of power too, but I doubt it caused the intake balance tube to crack venting the intake to the atmosphere at 60 hours past overhaul.
That hearing was orchestrated by our Congressman (Khanna) and Zoe Lofgren (not a member of the Subcommittee) to help add passion to their project to close Reid Hillview Airport… It was not to address potential lead issues at other airports… It wasn’t even to address more significant sources of lead in Santa Clara County, like paint and plumbing in older homes, pesticide residues and legacy lead from autogas. That is why FAA and EPA didn’t bother attending. And Cindy failed to mention that by banning sales of 100LL, 90% of Flight Operations at RHV today are flying with unleaded UL94 (by actual count of tail numbers from Tower logs…). That means that whatever lead there was is 90% gone, and so with it is any reason to close the airport. Thus the shift to racial and economic injustice as new theory… And please remember that Mogas in California does not come ethanol free… All gas for autos in the state must contain ethanol, so that is not an option…