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G100 UL

togaflyer

Well Known Member
I did some reading on Gami G100UL fuel that is working its way as a replacement for the 100 LL. This company has spent years developing a potential direct replacement for 100LL fuel. Reading their testing, they utilized a number of engines including a Turbo Continental TIO 550 with 8.7 to 1 compression ratio. This got me thinking about our experimental engines. I run 9:1 and I know there are engine that run up to 10:1, so I sent a question to Gami regarding how their fuel would work in higher compression engines. I received a response the same day, which I did not expect. Here is the answer received from Gami…….

The "lean rating" octane performance of the G100UL exceeds that of 100LL, so any engines that can run on 100LL will run well on G100UL.
That being said, the "rich rating" octane performance is WELL above that of 100LL (160+ octane equivalent). I don’t know what the limit of detonation-free compression ratio would be when full rich. That limit might be hard to find using currently available engine parts.

Thanks,

John-Paul
 
I saw a letter today from George Braly basically saying that it appears GAMI's G100UL unleaded avgas will not be FAA approved any time soon for fleet wide use, so don't hold your breath.

The letter is probably too political and critical of the FAA to publish here so I didn't.

Sad news indeed.:(

Let's hope the letter creates some positive action somehow.
 
I saw a letter today from George Braly basically saying that it appears GAMI's G100UL unleaded avgas will not be FAA approved any time soon for fleet wide use, so don't hold your breath.

The letter is probably too political and critical of the FAA to publish here so I didn't.

Sad news indeed.:(

Let's hope the letter creates some positive action somehow.

Indeed there seems to be something strange happening - no idea why this is taking so long. I'm struggling to understand why the FAA would be blocking progress on this.
 
Indeed there seems to be something strange happening - no idea why this is taking so long. I'm struggling to understand why the FAA would be blocking progress on this.

There's so much future profit involved. Yes, it's comparatively a drop in the bucket for Big Oil but...

If a company can politically position itself to supply a closed market, they gain and everyone else suffers. No one really expected this market to be ceded to niche players, did they? This won't be over until the situation is ultimately forced. Any lack of competition is gonna hurt, bad.
 
There's so much future profit involved. Yes, it's comparatively a drop in the bucket for Big Oil but...

If a company can politically position itself to supply a closed market, they gain and everyone else suffers. No one really expected this market to be ceded to niche players, did they? This won't be over until the situation is ultimately forced. Any lack of competition is gonna hurt, bad.

Nothing would stop a competitor to GAMI from having certified, and manufacturing and distributing, another unleaded fuel, absent interference from a regulating agency.

Or are you implying that the entrenched manufacturers had some influence over this?
 
GAMI isn't the only potential vendor to complain about how PAFI has been run by the FAA.

No telling what influences are at work here from the outside. The only thing we do know is that this has taken a very long time so far with little result. With multiple STCs approved a while back from 2 manufacturers and GAMI seemingly just being around the corner from fleet wide approval, this has now been moved out further into the future again.
 
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Nothing would stop a competitor to GAMI from having certified, and manufacturing and distributing, another unleaded fuel, absent interference from a regulating agency.

Or are you implying that the entrenched manufacturers had some influence over this?

I not intentionally implying but we all know how the world works. You can maintain your market share by being better or cheaper. Think Snap-on versus Harbor Freight. Both have a place in that market There are above board ways to lobby in order to get policy in your favor. There are other ways. I've been around too long to trust any side of a position when money is involved.

All that said, this assumes all of the associated bombastic verbosity prior to SnF was accurate; "the best position paper ever witnessed from a government entity" or whatever the exact words were. Will be interesting to see any related release from the FAA.

Would like to keep my 9.6:1s in my virgin engine but who knows?
 
I not intentionally implying but we all know how the world works. You can maintain your market share by being better or cheaper. Think Snap-on versus Harbor Freight. Both have a place in that market There are above board ways to lobby in order to get policy in your favor. There are other ways. I've been around too long to trust any side of a position when money is involved.

All that said, this assumes all of the associated bombastic verbosity prior to SnF was accurate; "the best position paper ever witnessed from a government entity" or whatever the exact words were. Will be interesting to see any related release from the FAA.

Would like to keep my 9.6:1s in my virgin engine but who knows?

Regulatory capture is a thing always and everywhere. Regulation is never a panacea and carries risks and problems of its own.
 
Aw, Dang

Braly actually says his fuel has been tested and fully FAA approved twice for all certified piston aero engines in the United States. The feds are now reviewing their certification system and standards. Again. They’ve enacted the EAGLE program to bring the fuel into use and they estimate only 8 years are needed to do so, after only 20 years of testing so far. Mmm, and I was SO looking forward to running aero engines without cleaning lead deposits off of spark plugs, pistons, valves, all that, along with sharply reduced oil contamination. Oh well.
 
There's so much future profit involved. Yes, it's comparatively a drop in the bucket for Big Oil but...

If a company can politically position itself to supply a closed market, they gain and everyone else suffers. No one really expected this market to be ceded to niche players, did they? This won't be over until the situation is ultimately forced. Any lack of competition is gonna hurt, bad.

Nothing would stop a competitor to GAMI from having certified, and manufacturing and distributing, another unleaded fuel, absent interference from a regulating agency.

Or are you implying that the entrenched manufacturers had some influence over this?

I not intentionally implying but we all know how the world works. You can maintain your market share by being better or cheaper. Think Snap-on versus Harbor Freight. Both have a place in that market There are above board ways to lobby in order to get policy in your favor. There are other ways. I've been around too long to trust any side of a position when money is involved.

All that said, this assumes all of the associated bombastic verbosity prior to SnF was accurate; "the best position paper ever witnessed from a government entity" or whatever the exact words were. Will be interesting to see any related release from the FAA.

Would like to keep my 9.6:1s in my virgin engine but who knows?

GAMI isn't the only potential vendor to complain about how PAFI has been run by the FAA.

No telling what influences are at work here from the outside. The only thing we do know is that this has taken a very long time so far with little result. With multiple STCs approved a while back from 2 manufacturers and GAMI seemingly just being around the corner from fleet wide approval, this has now been moved out further into the future again.

Not an update, per se'. Go about 20-ish minutes into the podcast for verification of suspicion (of suspicions) and status quo.

https://www.aopa.org/news-and-media/podcasts/podcasts/hangar-talk?utm_source=ebrief&utm_medium=email
 
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G100UL
UL94

Let’s just get it done. I have no interest in lead messing with my valves and engine in general.

Tinfoil hat firmly on…. The existing 100LL producers have a vested interest in stopping/slowing this down. So not a surprise there have been roadblocks in the way.
 
I often find it interesting that some have such full trust in the big companies and near zero trust in Federal government.
Me thinking, the companies have lots to gain financially while they keep their data secret with almost no accountability (Tabaco or oil industry) whereas Federal government has no skin in the game financially and there are accountable to the people (congressional hearings, etc.)
 
I often find it interesting that some have such full trust in the big companies and near zero trust in Federal government.
Me thinking, the companies have lots to gain financially while they keep their data secret with almost no accountability (Tabaco or oil industry) whereas Federal government has no skin in the game financially and there are accountable to the people (congressional hearings, etc.)

Generally I think you are right (in theory), but that doesn't really explain why the feds are not certifying this fuel as a 100LL replacement. Seems to be a no-brainer based on the GAMI side of the story.

Braly seems to indicate that he knows why he's being blocked, but is not saying why publicly. It would be fun to have an adult beverage with him and get his unfiltered views on this whole thing.
 
Reid Hill Switch Over

Lets see how fast Reid-Hill and other CA airports can switch over.

What becomes of swift 94UL?
 
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