GAMI Unleaded gets approval

[Pinecone]

14 hours ago, RobertGary1 said:

This is all I see in the type certificate for the M20F...

"Fuel 100LL or 100/130 octane min. grade aviation gasoline"

Gami fuel certainly meets the 100 octane requirement. So the question is simply what defines "aviation gasoline". I don't see the need for an STC since the existing type certificate doesn't seem to disallow Gami.

Except that from what I have read, G100UL is 98 octane or grade.  Or something like 98/140 with lean/rich rating.

In that case, your TDCS prohibits the use of it without the STC.

 

[Jerry 5TJ]

11 hours ago, T. Peterson said:

But if the consensus of all these smart guys on this forum is true and I am stuck with one high priced fuel option….

You have been stuck with one high priced option for decades.  

[Jerry 5TJ]

11 hours ago, ilovecornfields said:

I’ll bet you the JetProp can get an STC as well. No need to get jealous of us piston guys.

PT6A is already approved to burn gasoline, albeit with a greatly reduced TBO.  A few gallons of gasoline mixed into the JetA tanks isn’t even noticeable.

 Don’t try that mix in your IO-550.  

[GeeBee]

4 minutes ago, Jerry 5TJ said:

PT6A is already approved to burn gasoline, albeit with a greatly reduced TBO.  A few gallons of gasoline mixed into the JetA tanks isn’t even noticeable.

 Don’t try that mix in your IO-550.  

It can also keep the fuel bugs down!

[ilovecornfields]

1 hour ago, Jerry 5TJ said:

PT6A is already approved to burn gasoline, albeit with a greatly reduced TBO.  A few gallons of gasoline mixed into the JetA tanks isn’t even noticeable.

 Don’t try that mix in your IO-550.  

But is it approved for 100 LL or 100 octane or 98 octane 100 UL? You should probably buy the STC just to be safe in case you get ramp checked and the FAA starts draining your fuel tanks and tasting your fuel. 

[A64Pilot]

2 hours ago, Pinecone said:

Leaded fuel for road use was not banned until 1996, not 1976.

76 or the government is wrong

https://www.eia.gov/energyexplained/gasoline/gasoline-and-the-environment-leaded-gasoline.php

By 1975, unleaded gasoline was universally available. Effective January 1, 1996, leaded gasoline was banned by the Clean Air Act for use in new vehicles other than aircraft, racing cars, farm equipment, and marine engines.

In 96 it was totally banned but in my neck of the woods it had disappeared by 76 or maybe 77.

I thought it was banned in 76, but apparently not, just unavailable

Just like ULSD when it came out non ULSD was still legal for off road, but none existed in my part of the world.

‘But that does bring up another question, when we went to unleaded fuel in cars, valve recession and burning valves became a problem. The manufacturers fixed that with Stellite valve seats and I believe sodium filled valves, Lycomings have sodium filled valves, Conti’s don’t but I don’t know what the seats are.

[Shadrach]

1 hour ago, Pinecone said:

Except that from what I have read, G100UL is 98 octane or grade.  Or something like 98/140 with lean/rich rating.

In that case, your TDCS prohibits the use of it without the STC.

 

Can you link where you read that? According to GAMI’s website and this Avweb interview with George and Tim, G100UL was more resistant to detonation than ASTM D90 100LL. 

 

 

[GeeBee]

The PT6A is approved for any octane avgas conforming  to Mil-G-5572 up to 150 hours by TCDS .

Note the word “conforming”

[Shadrach]

1 hour ago, A64Pilot said:

76 or the government is wrong

https://www.eia.gov/energyexplained/gasoline/gasoline-and-the-environment-leaded-gasoline.php

By 1975, unleaded gasoline was universally available. Effective January 1, 1996, leaded gasoline was banned by the Clean Air Act for use in new vehicles other than aircraft, racing cars, farm equipment, and marine engines.

I can remember leaded road gas in the 80s but it was not recommended for use in vehicles with catalytic converters. Leaded road gas was killed as much by a lack of demand as government ban. Of course the lack of demand was fostered by the widespread installation of Catalytic Convertors which prohibited its use.

[MikeOH]

2 hours ago, Jerry 5TJ said:

You have been stuck with one high priced option for decades.  

Ah, so now we’ll be stuck with an even HIGHER priced fuel. How, exactly, is that better?

[A64Pilot]

Ref the Octane of the Gami fuel

Octane is sort of irrelevant, only thing that matters is detonation resistance.

See Octane is almost a term like pretty, depending on what method is used to measure it, the same fuel can have different octane ratings, but what’s more important is that chemically different fuels with identical octane ratings may be more or less likely to detonate, so why we think of Octane is the end all for detonation resistence but maybe it’s not, when you change the chemistry maybe Octane testing isn’t as accurate.

We as consumers like to have numbers so we can compare the superiority of one product to another, like Stereos of years past when people cared about stereo quality, we would buy one amp that claimed .001% Total Harmonic Distortion over one that advertised .01, but that was totally irrelevant, the difference was negligible.

Only point is that Octane is only a small part, more important is when you take that motor with 500F heads, max oil temp and high intake temps and crank up the MP.

Which brings up why hasn’t Lycoming tested this stuff, don’t tell me they can’t don’t have the equipment etc., because they certainly do.

[A64Pilot]

34 minutes ago, GeeBee said:

The PT6A is approved for any octane avgas conforming  to Mil-G-5572 up to 150 hours by TCDS .

Note the word “conforming”

Without trying to be an Ass, I don’t think most understand what your trying to point out.

I do I think and it makes me wonder things about engine warranties etc. cause we won’t be

burning a “conforming” fuel. Most don’t realize how powerful that word is in aviation, it’s the holy grail, does the aircraft and or component parts, petroleum, fuel and lubricants conform to TCDS or accepted standards?

See I went down the road a few years ago trying to Certify our aircraft to burn Bio-Diesel, it was already Certified to burn Diesel.

We never got there and the biggest reason was there is no accepted ASTM or other standard of what Bio-Diesel is, there is for petroleum Diesel, so we could Certify to that, but not Bio, not without a Standard, because without a standard you had no idea what temp it would turn to jello or all kinds of other possible problems.

‘Maybe even though we were the Type Certificate holder we should have gone the STC route ?

[aviatoreb]

1 hour ago, ilovecornfields said:

But is it approved for 100 LL or 100 octane or 98 octane 100 UL? You should probably buy the STC just to be safe in case you get ramp checked and the FAA starts draining your fuel tanks and tasting your fuel. 

Yes...

Well the time when most infractions are found are when there is an incident or a crash of some kind.  Just don't go crashing with the wrong fuel without the STC.  

[ilovecornfields]

30 minutes ago, aviatoreb said:

Yes...

Well the time when most infractions are found are when there is an incident or a crash of some kind.  Just don't go crashing with the wrong fuel without the STC.  

I try not to crash even with the right fuel!

Just seems like a lot of people getting really worked up over nothing. Must be nice to not have anything else to worry about these days than the price of a fuel you can’t even buy yet. 

If I crash my plane, whether or not I’ve met a paperwork requirement really doesn’t matter to me. 

[Hank]

23 minutes ago, ilovecornfields said:

If I crash my plane, whether or not I’ve met a paperwork requirement really doesn’t matter to me. 

But everyone in Washington knows that incorrect or missing paperwork is at least a contributing factor to airplane accidents, if it's not the cause! Our planes won't fly if the paperwork isn't there . . . . .

[Shadrach]

1 hour ago, A64Pilot said:

Ref the Octane of the Gami fuel

Octane is sort of irrelevant, only thing that matters is detonation resistance.

See Octane is almost a term like pretty, depending on what method is used to measure it, the same fuel can have different octane ratings, but what’s more important is that chemically different fuels with identical octane ratings may be more or less likely to detonate, so why we think of Octane is the end all for detonation resistence but maybe it’s not, when you change the chemistry maybe Octane testing isn’t as accurate.

We as consumers like to have numbers so we can compare the superiority of one product to another, like Stereos of years past when people cared about stereo quality, we would buy one amp that claimed .001% Total Harmonic Distortion over one that advertised .01, but that was totally irrelevant, the difference was negligible.

Only point is that Octane is only a small part, more important is when you take that motor with 500F heads, max oil temp and high intake temps and crank up the MP.

Which brings up why hasn’t Lycoming tested this stuff, don’t tell me they can’t don’t have the equipment etc., because they certainly do.

1) what's in it for Lycoming? If FAA and GAMI are taking on the responsibility of Certification why would an engine manufacture enter the fray? By not approving nor prohibiting the fuel they stay out of the liability chain and have the option to blame any engine issues on the new fuel. 

2)I have no doubt that Lycoming has a test stand.  I have serious doubts that it is as sophisticated as GAMI's test cell.

[T. Peterson]

4 hours ago, Jerry 5TJ said:

You have been stuck with one high priced option for decades.  

Maybe not decades as I have only owned an airplane for 6 months. But that not withstanding, I didn’t have to buy my airplane and then buy a license (STC) to put gas in it!!

My understanding is that if I CHOOSE to make a modification to my airplane because I like whatever gizmo so and so has developed, I must have an STC because I am MODIFYING my SPECIFIC airplane and must demonstrate the safety of said gizmo in my application.

In this instance I am modifying absolutely nothing, but being forced to provide an STC for something that the government has already declared safe for airplane engines! In my opinion that is utterly incoherent. As far as that somehow cheats the developer is ludicrous as I am buying his product.....actually forced to buy his product unlike any other actual modification I may choose to put on my airplane.

Someone once said that logical hell is where reason no longer matters. I think I have arrived.

[EricJ]

6 hours ago, GeeBee said:

AC 20-24D is guidance for the TCDS applicant, not the end user. What it is telling you is how to construct the certification of an engine  and how to word the TCDS with respect to fuel and oil. It is telling the TCDS applicant that when they say "Grade 100 Aviation fuel" the FAA takes that to mean ASTM specification.

Where does it say that?   It doesn't even say that in the places that you quote and underline.

[A64Pilot]

It’s an STC because that was the only way to get there by a small company. There is no collusion to squeeze bucks from anyone I’m sure, but I would feel a whole lot better if this stuff had gone through the same approval that 100LL did when it replaced the high content lead fuels.

Why would Lycoming test, what’s in it for them? It going into their engines that’s what.

If Lycoming had tested the Mobil 1 oil, could we have prevented that fiasco? 

I know what happens to an old auto engines valve trains when you run UL in it, that can be mitigated by removing the heads and replacing the valves and seats, there are I believe no modern auto engines with flat tappet cams too because the additives required to not make them wear were removed from modern oil to protect catalytic convertors. But cars come and go, new designs replace old ones, they evolve.

But I’ve always said with aircraft we fly behind our Grandfathers engines, nothing of any real significance has changed in decades. We may have Stellite valve seats already, I don’t know.

Will we suffer from valve recession? No idea but I am certain no short term duration test can tell us anything, you’ll know hundreds of hours into it, just like the oil thing.

[A64Pilot]

5 hours ago, GeeBee said:

That is why there is an airframe AML in addition to an engine AML.

But you know not every airframe or components have actually been tested. I’m sure some O-rings and pieces of fuel cells have been put in a bucket for a period of time and we think we know the properties of these chemicals as I’m sure they are all existing aromatics I suspect that are in auto gas now, but I’m certain there has been no real long term testing.

Why am I certain? because if there had we would have heard about it.

We have two groups, one thinks the world of the Gami folks, while others are a little more conservative, I’m more conservative, no one want this stuff to work as has been promised than I do, but I’ve seen miracle additives come and go.

Fingers crossed, because I want it to work, and hope it’s priced to not cost much more. 

I’m holding my breath there too, but we will see

[GeeBee]

15 minutes ago, EricJ said:

Where does it say that?   It doesn't even say that in the places that you quote and underline.

1. Purpose. This advisory circular (AC) change updates the references provided in the original document. This advisory circular (AC) provides guidance applicable to adding fuels and oils as engine, aircraft, or auxiliary power unit (APU) operating limitations. It also provides guidance on fuel and lubricating oil specifications and standards, and on propulsion fuel and/or lubricating oil certification plans.

Who sets the operating limitations? You or the TCDS or STC applicant?

[EricJ]

8 minutes ago, mike261 said:

WHY DO I NEED AN STC TO USE THE FUEL?

The FAA requires a supplemental type certificate (STC) to be issued when an aircraft owner has “received FAA approval to modify an aeronautical product from its original design.” This far-reaching definition of modification includes the approval to use a fuel not specified for the original design or in the original flight manual or pilot operating handbook (POH).

 

this From AOPA. 

The fuels specified by the TCDS and POH are in terms of minimum "octane" or "grade".   If a fuel meets those, then it meets the TCDS and POH fuel placard and an STC isn't necessary.    Those terms are not well-defined, though, so it remains to be seen how this plays out.   Obviously there's much room for confusion, and none of the candidate fuels are yet available for sale, so how it ends up is still TBD.

 

 

[jaylw314]

17 minutes ago, T. Peterson said:

Maybe not decades as I have only owned an airplane for 6 months. But that not withstanding, I didn’t have to buy my airplane and then buy a license (STC) to put gas in it!!

My understanding is that if I CHOOSE to make a modification to my airplane because I like whatever gizmo so and so has developed, I must have an STC because I am MODIFYING my SPECIFIC airplane and must demonstrate the safety of said gizmo in my application.

In this instance I am modifying absolutely nothing, but being forced to provide an STC for something that the government has already declared safe for airplane engines! In my opinion that is utterly incoherent. As far as that somehow cheats the developer is ludicrous as I am buying his product.....actually forced to buy his product unlike any other actual modification I may choose to put on my airplane.

Someone once said that logical hell is where reason no longer matters. I think I have arrived.

That may be, but AFAIK STC is not just used to prove a modification is safe.  There is some degree of "ownership" of information used to approve it that is implied by the process.   

Heck, you're forced to buy the OS license to use the computer you own.  Some might even argue you have a "choice" to use a free OS like Linux, but realistically you can't because the world uses Microsoft or Apple.  That's free market for you.

[GeeBee]

51 minutes ago, T. Peterson said:

Maybe not decades as I have only owned an airplane for 6 months. But that not withstanding, I didn’t have to buy my airplane and then buy a license (STC) to put gas in it!!

My understanding is that if I CHOOSE to make a modification to my airplane because I like whatever gizmo so and so has developed, I must have an STC because I am MODIFYING my SPECIFIC airplane and must demonstrate the safety of said gizmo in my application.

In this instance I am modifying absolutely nothing, but being forced to provide an STC for something that the government has already declared safe for airplane engines! In my opinion that is utterly incoherent. As far as that somehow cheats the developer is ludicrous as I am buying his product.....actually forced to buy his product unlike any other actual modification I may choose to put on my airplane.

Someone once said that logical hell is where reason no longer matters. I think I have arrived.

How is it different than for instance a very expensive AD like the Lycoming 540 where they said, "buy a new crankshaft". Welcome to aviation, we are all one AD from parking our airplanes. Be glad this is a cheap deal.

[EricJ]

3 minutes ago, GeeBee said:

1. Purpose. This advisory circular (AC) change updates the references provided in the original document. This advisory circular (AC) provides guidance applicable to adding fuels and oils as engine, aircraft, or auxiliary power unit (APU) operating limitations. It also provides guidance on fuel and lubricating oil specifications and standards, and on propulsion fuel and/or lubricating oil certification plans.

Who sets the operating limitations? You or the TCDS or STC applicant?

You didn't answer the question.    Where does it say:

"It is telling the TCDS applicant that when they say "Grade 100 Aviation fuel" the FAA takes that to mean ASTM specification."

It actually says that it isn't required.