100LL Debacle

Yes, it is; it's what's in dry gas.


Back in the 1980s the airport management asked us to pour our used oil on the [dirt] airport road to keep the dust down.

The airport I'm at today burns it to heat the maintenance hangar.



That's a state rule for mogas. The G100UL spec allows no ethanol at all.

I was sincerely hoping that would be the case but I never expect the gov't to make a whole lot of sense, particularly when it comes to environmental issues.
 
IBut, methanol attacks aluminum and other bright metals. That why it is no longer used in mogas after some spectacular failures in the early 80’s. We’ve got even more aluminum wetted by fuel in airplanes. Methanol would be a bad thing. Even for your car, it’s best to avoid dry gas products with methanol. Instead, look for those with isopropanol (isopropyl alcohol). That’s MUCH more benign to the metals in your fuel system.

And methanol is hydrophilic. That's why it works as dry gas.
 
Not a collaborative group!
If they were there would only be one standard. Have seen the inner workings of the RTCA but can only imagine how the ATSM or SAE are when jockeying for position on a global level.
 
Exxon, I think, Used to market an aviation synthetic blend.

ExxonMobil Elite was a semisynthetic multi weight oil with a corrosion inhibitor similar to CamGuard included in the blend. Regrettably, it was discontinued. It was not price competitive with Aeroshell or Phillips multiweight oil.
 
There was a Mobil AV1 full synthetic oil that was withdrawn for a number of issues. Gets confused with Exxon Elite since Exxon merged with Mobil.
 
[QUOTE="PaulMillner, post: 3304465, .....
a couple years of FAA rulemaking activity. Blanket STCs aren’t a thing today, and apparently not easy to accomplish legally for the FAA.

Paul[/QUOTE]
Thankyou Mr Millner. I've learned a lot from your post here and the article you've written.
 
This might interest a few of you…. Lycoming jumps in early on the oil change question
 

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I'm heavily biased to Shell Rotella T for the diesels <snip>

I have at least three gas burning engines that really like Shell Rotella T4 15W-40! Works very well in the older flat tappet engines ... :)
 
This might interest a few of you…. Lycoming jumps in early on the oil change question
April 2017? I guess that was in response to UL94?

Also, who is going to be changing the oil every other filter replacement?
 
So, an STC is required to legally use G100. Swift is also pursuing the STC route. Then there are the EAGLE participants, operating under some other licensing arrangement. Assuming there are eventually multiple approved fuels competing in the marketplace, sounds like chaos. Is there a plan?
 
So, an STC is required to legally use G100. Swift is also pursuing the STC route. Then there are the EAGLE participants, operating under some other licensing arrangement. Assuming there are eventually multiple approved fuels competing in the marketplace, sounds like chaos. Is there a plan?

A lot of times the first player in a market isn't the one that gains traction. VHS vs Betamax for example.

I'm not sure I'll jump the gun with a STC purchase until I see what my home airport decides to do. It's hard to imagine there being more than one fuel because it's my understanding that fuel suppliers want to be the exclusive fuel supplier at any given location. There's going to be some jockeying behind the scenes, positioning, deal making. Seems like the best thing to do is wait and see what develops.
 
I guess that was in response to UL94?
And UL91 in Europe. If using UL avgas, going 100 hrs on the oil per the bulletin is not really an issue. The oil doesn't wear out as much as it gets contaminated of which lead was a large percentage. Its a lot less problematic than the current supply driven issues to skip the filter changes and only change the oil. I think once UL becomes the predominant avgas out there you'll see further extensions on oil changes perhaps out to 150 or 200 hours except those engines/aircraft with ADs limiting the oil change to no more than 100 hrs.
 
Agreed! I suspect the savings from improved oil and spark plug and engine life will more than offset the extra cost of UL fuel, and the STC will pay for itself.

I think there will be significant demand for GAMI gas - from pilots, from communities, from airports, and from the EPA. Hopefully that demand will motivate companies to get the fuel into production and distribution more quickly than expected.
 
I think that would challenge the acid buffering of the oil...
If that is along the same lines as additive depletion and other degrade actions on the oil I seem to recall several discussion on way to mitigate those issues with conventional oil. Regardless if they can get a synthetic product to work in recips that could definitely take it to the next level.

On the small turbine side we had routinely extended OEM oil change intervals from 200 to 600 hrs by simply adding a secondary external oil filter. Granted there's a difference in engine operating parameters but the "newer" gen synthetic oils made it all possible. I would surmise the same would be true with recips with the right oil blend and filtration.
 
And methanol is hydrophilic. That's why it works as dry gas.
Hygroscopic is a more appropriate descriptor. Sorry for being pedantic. I used to burn methanol by the drum in my kart racing days and rigged a pressure system with Argon to ‘push’ it out of the drum and never expose the stored methanol to the atmosphere since I live in a very humid climate.
 
A lot of times the first player in a market isn't the one that gains traction. VHS vs Betamax for example.

I'm not sure I'll jump the gun with a STC purchase until I see what my home airport decides to do. It's hard to imagine there being more than one fuel because it's my understanding that fuel suppliers want to be the exclusive fuel supplier at any given location. There's going to be some jockeying behind the scenes, positioning, deal making. Seems like the best thing to do is wait and see what develops.

You will probably only see one fuel at a given field. But you may have different fuels at different fields, even in a given region. But definitely flying from region to region.

The good news is, the GAMI STC will be a by a website, so if you are at a field with GAMI and you only have a Swift STC, you can use your iPad to buy the STC. :D
 
I think that would challenge the acid buffering of the oil...

Reintroduction of aviation-tailored synthetic oil promises less engine wear and lower operating temperatures. I'll sign up for that!

Paul

But then again, in cars we went from 3,000 mile oil change intervals to 15,000 mile change intervals. :)

But less wear and lower temps are very good things.
 
Note the 100 hour oil changes still have the caveat of "or every 4 months, whichever is first". For flight schools, this is significant, for the average spam can owner, it isn't, because most hit 4 months before 100 hours. Of course, there are plenty who only change the oil every annual, whether it needs it or not... :eek:
 
You will probably only see one fuel at a given field. But you may have different fuels at different fields, even in a given region. But definitely flying from region to region.

That's my concern: that you will need more than one STC, plus whatever licensing arrangement may come out of EAGLE.
 
Of course, there are plenty who only change the oil every annual, :eek:

I'm still alive tho *shrugs*. At least you had the couth to not offer money to inscribe my gravestone mocking my death, like one classy mf'er over on the Piper board offered to do when I raised objections over the ERAU moral hazard AD. So thank you for staying classy. :D

I will say this much. Thanks to our failed national strategy policy, there's pRide iN owNersHip dodo birds right now incurring oil changes with the same oil filter. And they think I'm the pounds-foolish in the room? lol. I digress. TETO.
#stillalive
 
You gotta wonder why they're charging for the STC since they're getting a cut on every gallon sold. Seems a free STC would only increase fuel sales.
 
You gotta wonder why they're charging for the STC since they're getting a cut on every gallon sold. Seems a free STC would only increase fuel sales.


Why not? Maybe the STC will become free once there’s a competitor, but now?
 
You gotta wonder why they're charging for the STC since they're getting a cut on every gallon sold. Seems a free STC would only increase fuel sales.
I think once the UL guys get the bills paid and things stabilize the STCs in general will become public domain. I would really hate to see they're final R&D expenditure. However, I think the UL developers are on a finite schedule as I believe the industry standards will be updated which will null and void any STC or other approval requirement. They're also working the same route for SAF on the turbine/jet side.
 
...I believe the industry standards will be updated...


Sure, but that update will likely move at the speed of a bureaucratic snail chasing an FAA turtle across a field of red-tape peanut butter.

GAMI will have years of STC sales if they want them. Environmental concerns will shove the change to UL along much faster than the fuel standard can be revised, and fuel suppliers will have to sell GAMI gas or invent, test, and STC their own fuels.

Getting a license from GAMI will be the path of least resistance for fuel suppliers to sell UL juice.
 
but that update will likely move at the speed of a bureaucratic snail
I don't think it will it from what I've seen and read on the SAF side. The G100 approval was a benchmark in the process. Besides the standards updating is apart from the regulatory side per se and runs at its own speed, determine and influence. Given the current climate so to speak I think SAF and UL AVGAS will become a feature everywhere sooner than later. And years sooner than most think.
 
Because George wants to have some of this money while he's still on the planet. From a practical perspective, even if 25% of the GA fleet, about 50,000 planes, pay, on average $150 for the STC, That's only $7.5M, which isn't a lot for all the time and expense he has put into this effort. Heck, even if it is $20M, I'm not going to be the one to argue him and his team doesn't deserve it.
 
This could add a whole new chapter of flight planning for the AIM, “how to find approved fuel without running out”.
 
in cars we went from 3,000 mile oil change intervals to 15,000 mile change intervals.
Cars don't have the loose-tolerance air-cooled engines, with very large pistons, that we do... so the blowby, that creates the oil acidity problem, is an order of magnitude smaller... or maybe two orders?

Paul
 
Hygroscopic vs Hydrophilic
  • Hydrophilic − Refers to substances that absorb water. A hydrophilic substance will bond, on a molecular level with water.
  • Hydrophobic − Refers to materials that will repel water.
  • Oleophilic − Refers to a substance that absorb oils or nonpolar liquids.
  • Oleophobic − Refers to a substance that repels oils or nonpolar liquids.
  • Hygroscopic − Refers to the ability of a material to absorb humidity from the air. A hygroscopic substance will actively attract and absorb water, without bonding. (A hygroscope is an instrument that indicates changes in humidity.)
 
I really don’t know why you guys are fussing so much. The STC will cost less than the flight to KGMU for a POA social. Or, am i misjudging y’all?
I'm not fussing, just curious about the business plan. Flying an experimental, I don't need an STC to use any alternative fuel.
 
  • Hydrophilic − Refers to substances that absorb water. A hydrophilic substance will bond, on a molecular level with water.
  • Hydrophobic − Refers to materials that will repel water.
  • Oleophilic − Refers to a substance that absorb oils or nonpolar liquids.
  • Oleophobic − Refers to a substance that repels oils or nonpolar liquids.
  • Hygroscopic − Refers to the ability of a material to absorb humidity from the air. A hygroscopic substance will actively attract and absorb water, without bonding. (A hygroscope is an instrument that indicates changes in humidity.)
You forgot Deliquesant. :p
 
Cars don't have the loose-tolerance air-cooled engines, with very large pistons, that we do... so the blowby, that creates the oil acidity problem, is an order of magnitude smaller... or maybe two orders?

Paul
I suspect that the lack of PCV is a much bigger factor in the rate of crap buildup in the crankcase.
 
One of my concerns is that the sole remaining source of tetraethyl lead will be shut down prematurely
 
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