Based on the G100UL fuel leak thread what's your position?

[A64Pilot]

The reason given to me why Georgia pumped so much money into Rural airports was in the hope to bring in Business.

‘There was some formula, I think if there wasn’t a runway within 50 miles of your little airport and your runway wasn’t at least 5,000 ft, the Government through a grant would pay for your runway to be extended, they also built hangars and new FBO buildings. The theory was that your little town was more likely to get Companies to build there if there was a Biz Jet runway in the town.

In my part of the world hunting, particularly Quail hunting is big business, in Camilla for instance when the new T hangars were built the tied down aircraft were given use of the old shade hangars for free, it wasn’t just being nice, it was to have the ramp space for the Biz Jets bringing in hunters, and these wealthy hunters spend big on their hunting trips enriching the local economy.

Attached pic is Camilla Ga with the morning deliveries of hunters in their Jets

When I was a kid in the 60’s these hunts went for $1,000 a day per hunter. I assume they are likely five times that at least today? If so and there are an average of 20 hunters, then $100K a day for a little rural town is good money for the local area.

Edited Tuesday at 01:23 PM by A64Pilot

[GeeBee]

12 hours ago, ragedracer1977 said:

What’s this property tax thing you speak of? 

It is the money that keeps the airport in the green and out of the hands of developers.

[Marc_B]

EAA weighs in and cautions use of G100UL in experimentals. Says STC doesn’t apply to experimental aircraft so may not have even tested/considered the methods and products in use for experimental builds. 

[redbaron1982]

Is there any news re FAA investigation into this? Is G100UL still available at the two Kali airports? Are there any new aircraft having issues?

[PT20J]

Here's a solution for all you folks that live in California but seem displeased with the state:

https://www.nbcnews.com/news/world/denmark-should-buy-california-petition-trump-greenland-rcna191806

[mluvara]

2 hours ago, redbaron1982 said:

Is there any news re FAA investigation into this? Is G100UL still available at the two Kali airports? Are there any new aircraft having issues?

Let’s just say that I looked at another Cessna 421 this weekend that’s worse than the first one.

Edited Wednesday at 06:07 PM by mluvara

[ragedracer1977]

On 2/12/2025 at 7:34 AM, Marc_B said:

EAA weighs in and cautions use of G100UL in experimentals. Says STC doesn’t apply to experimental aircraft so may not have even tested/considered the methods and products in use for experimental builds. 

Does this mean, like I suggested way way back, that an experimental aircraft can buy G100UL without buying the STC?

[redbaron1982]

8 minutes ago, ragedracer1977 said:

Does this mean, like I suggested way way back, that an experimental aircraft can buy G100UL without buying the STC?

That's my understanding... AFAIK an experimental aircraft does not have a type certificate... so how would get a supplement to something you don't have in the first place.

[Marc_B]

It just means that as with most changes to an initial design and implementation, the owner/builder/maintainer assumes responsibility and liability.

if GAMI didn’t test your aircraft for use…what testing did you do to insure an STC for another aircraft is safe or applicable?

If something happens, do you have the STC testing information from GAMI/FAA to back your use and adoption? 

[mluvara]

1 hour ago, ragedracer1977 said:

Does this mean, like I suggested way way back, that an experimental aircraft can buy G100UL without buying the STC?

A good reference direct from the EAA is here : https://www2.eaa.org/eaa/news-and-publications/eaa-news-and-aviation-news/2025-02-06-field reports highlight need to assess e-ab aircraft prior to using g100ul

"As the builders and owners of E-AB aircraft, we are in the unique position of making our own determination with regard to the use of any new fuel. These industry reports highlight the need for each owner to assess the potential impact of using G100UL or any other new fuel on their aircraft before they introduce it to their tanks. This should include a review of the materials used throughout their fuel systems, including fuel tank sealants, gaskets, O-rings and hoses, as well as any other materials which could come into contact with the fuel either through normal operation or in the event of a spill or leakage. "

Nov 2024 Sport aviation also has an article on it (pg 98) 

https://sportaviation.mydigitalpublication.com/november-2024/page-98

 

Also this: https://www2.eaa.org/eaa/news-and-publications/eaa-news-and-aviation-news/2025-01-24-eaa-response-to-aopa-on-avgas

 

Edited 23 hours ago by mluvara

[ragedracer1977]

20 minutes ago, mluvara said:

A good reference direct from the EAA is here : https://www2.eaa.org/eaa/news-and-publications/eaa-news-and-aviation-news/2025-02-06-field reports highlight need to assess e-ab aircraft prior to using g100ul

"As the builders and owners of E-AB aircraft, we are in the unique position of making our own determination with regard to the use of any new fuel. These industry reports highlight the need for each owner to assess the potential impact of using G100UL or any other new fuel on their aircraft before they introduce it to their tanks. This should include a review of the materials used throughout their fuel systems, including fuel tank sealants, gaskets, O-rings and hoses, as well as any other materials which could come into contact with the fuel either through normal operation or in the event of a spill or leakage. "

Nov 2024 Sport aviation also has an article on it (pg 98) 

https://sportaviation.mydigitalpublication.com/november-2024/page-98

 

Also this: https://www2.eaa.org/eaa/news-and-publications/eaa-news-and-aviation-news/2025-01-24-eaa-response-to-aopa-on-avgas

 

The reason I bring it up is because GAMI has said in the past that it would not be legal to purchase the fuel unless you had the STC.

[Marc_B]

22 minutes ago, ragedracer1977 said:

not be legal to purchase the fuel unless you had the STC.

GAMI requires an STC for purchase and use of their fuel.  Mr. Braly has said that he'd help with paperwork to update the FAA for use of G100UL in experimental aircraft.  But we're talking about different things here.

1) to legally purchase G100UL, GAMI requires STC.

2) to legally use G100UL in a certified aircraft, FAA and GAMI require STC.

3) to legally use G100UL in an experimental aircraft, I believe an owner/builder needs to fill out paperwork with the FAA with design modifications, and would still need to purchase the STC from GAMI to legally purchase fuel.

Can you pump fuel without holding an STC?? I'm sure you probably can depending on the FBO.  But in these early stages of alternative fuels, why wouldn't you want as much liability backing and be "above board" to have others with you with any issues?

[ragedracer1977]

9 minutes ago, Marc_B said:

GAMI requires an STC for purchase and use of their fuel.  Mr. Braly has said that he'd help with paperwork to update the FAA for use of G100UL in experimental aircraft.  But we're talking about different things here.

1) to legally purchase G100UL, GAMI requires STC.

2) to legally use G100UL in a certified aircraft, FAA and GAMI require STC.

3) to legally use G100UL in an experimental aircraft, I believe an owner/builder needs to fill out paperwork with the FAA with design modifications, and would still need to purchase the STC from GAMI to legally purchase fuel.

Can you pump fuel without holding an STC?? I'm sure you probably can depending on the FBO.  But in these early stages of alternative fuels, why wouldn't you want as much liability backing and be "above board" to have others with you with any issues?

How do you require an STC to purchase something that doesn't require one and theoretically can not legally be applied to an non-certificated airplane?  I'm under the impression that an STC controls the legal USE of the product in a certified airplane.  I know Garmin et.al. want you to buy the STC for certified airplane, but they will sell you the product without for experimentals.

I guess what am asking is - If a Vans RV pulled up to the self serve and pumped G100UL without an STC purchased from GAMI, what is being violated - in a legal sense.

Edited 22 hours ago by ragedracer1977

[redbaron1982]

8 minutes ago, Marc_B said:

...

1) to legally purchase G100UL, GAMI requires STC.

...

Is this even legal?

[varlajo]

11 minutes ago, ragedracer1977 said:

If a Vans RV pulled up to the self serve and pumped G100UL without an STC purchased from GAMI, what is being violated - in a legal sense.

Great question. In this scenario, no business transaction occurs and no relationship is established between GAMI and RV owner. 

[mluvara]

The topic of E-AB is a muddy one that is not clearly defined (as far as I can tell) on GAMI's website or otherwise. 

One can walk up to the pump at Watsonville (WVI) and purchase G100UL. When you select G100UL in the kiosk, it simply says something like 'May require STC'. Numerous experimental aircraft at Watsonville have likely done this.

Reid Hillview (RHV) only sells from the truck and requires paperwork to be filled out prior to one filling up.

There is this video where George described experimental usage.

I believe further official guidance on this is required.

Michael

 

 

 

[Marc_B]

I read this differently.  E-AB aircraft sometimes use different techniques, construction, and materials than certified aircraft.  Given that GAMI went through the STC process and isn't openly sharing what materials were tested and how, this makes the use of an alternative fuel from this pathway more difficult for an E-AB owner/operator to determine if it is safe for their aircraft, especially for early adoption where there's limited field testing.

If you decided to forgo the STC and just "fuel up"...what liability coverage do you have from Vitol, GAMI, or your FBO?  Even if you obtain the STC, what testing did you do to ensure that G100UL is safe in your airframe if you can't reliably refer to similar product testing that GAMI may or may not have performed?

Regarding whether it's legal or not to purchase fuel without purchasing an STC is a distant concern compared to the above in my mind.

[Paul Thomas]

Experimental do not require an STC to use alternative fuels, just like they don't need an STC to put an alternative engines. It's all up to the owner/builder.

[GeeBee]

https://www.avweb.com/aviation-news/eaa-cautions-e-ab-builders-operators-on-g100ul-usage/

[A64Pilot]

11 hours ago, Paul Thomas said:

Experimental do not require an STC to use alternative fuels, just like they don't need an STC to put an alternative engines. It's all up to the owner/builder.

I do several yearly Condition inspections for neighbors for Experimentals and LSA’s

Fuel is among the least of their concerns for many, for example it’s extremely common even for factory built LSA’s to have plastic as in what I swear is ice maker waterline brake lines, one Pitts even has clear vinyl fuel lines inside of the cockpit, I guess the builder thought seeing the fuel has value.

Having said that some of the highest quality, best built aircraft I have seen are Experimental, it’s all up to the builder.

 

[Justin Schmidt]

1 hour ago, A64Pilot said:

I do several yearly Condition inspections for neighbors for Experimentals and LSA’s

Fuel is among the least of their concerns for many, for example it’s extremely common even for factory built LSA’s to have plastic as in what I swear is ice maker waterline brake lines, one Pitts even has clear vinyl fuel lines inside of the cockpit, I guess the builder thought seeing the fuel has value.

Having said that some of the highest quality, best built aircraft I have seen are Experimental, it’s all up to the builder.

 

They may see more fuel than they bargained for, and at the worst time 

[mluvara]

15 hours ago, Marc_B said:

If you decided to forgo the STC and just "fuel up"...what liability coverage do you have from Vitol, GAMI, or your FBO?  Even if you obtain the STC, what testing did you do to ensure that G100UL is safe in your airframe if you can't reliably refer to similar product testing that GAMI may or may not have performed?

Regarding whether it's legal or not to purchase fuel without purchasing an STC is a distant concern compared to the above in my mind.

There's two issues here and sorry if I conflated them

1. Ability/legality of purchasing fuel (with or without STC)
2. Approval acceptable to FAA to utilize fuel in an aircraft (STC, fleet wide, field approval, etc)

Is there something documented that says non-certificated aircraft have to purchase an STC?  I was surprised that one could walk up to the pump at Watsonville (WVI) and self-serve G100UL. I see no provisions on the G100UL STC site for airplanes not on the AML to purchase an STC. As stated, one cannot apply an STC to an aircraft without a type certificate I would use the term 'aircraft' if anything other than airplanes were approved. However, it may be that a company chooses to sell a 'data package' as part of some STC like process for a user to determine compatibility with non part 23 / CAR 3 aircraft.

The following statement  has been made by GAMI on several occasions.

"The reality is that every single [certified] spark ignition piston powered airplane is approved to use G100UL Avgas.  Without exception.  That approval covers about 98+% of all of the piston powered aircraft found in the FAA type certificate data base. “

There is confusion by many regarding the term 'drop-in' and 'fleet wide FAA Approval' which has likely led some to believe they can just fuel up their E-AB without verifying compatibility (either logbook entry stating it was determined to be compatible or re-enter phase 1 testing).  The reality is that not all aircraft are permitted to use G100UL without additional steps (some likely are lengthy). Here's my understanding of it:

• Part 23 and CAR 3 airplanes <- On the AML, good to go with STC purchase and 337 form
• Rotorcraft <- not net approved via STC (been in the works)
• S-LSA <- needs to be approved by manufacturer (e.g. RV-12)
• Experimental aircraft (E-AB, Warbirds),etc <- builder/owner has to determine compatibility prior to use (really need data/testing to do so)
• Special, Limited, Restricted Category, etc (e.g many warbirds,etc) <- not on AML, requires a field approval (via data)

It's clear that currently not ALL aircraft are blanket approved and many may require special approval.

Good description by the FAA here about pathways and approvals for special aircraft.

 

Edited 4 hours ago by mluvara

[MikeOH]

My $0.02 as an armchair (recliner couch, actually) lawyer regarding the legality of BUYING G100UL:

ANYONE can buy the fuel from a vendor without a GAMI STC and there is nothing GAMI can do to the buyer about it.  Your contract is with the fuel vendor, NOT GAMI. No way for GAMI to sue you, the buyer.

If GAMI wants to stop the practice they will need to sue the fuel distributor/vendor and make THEM police the purchase of G100UL.  Seems like a pretty poor marketing strategy to me.

The whole STC thing is a red-herring with regard to the PURCHASE of the fuel itself.  The STC is required by the FAA, NOT GAMI.  GAMI holds the rights to the STC and can, therefore, charge for the STC.

The STC is required by the FAA for CERTIFICATED aircraft, but NOT EAB. Therefore, fueling a CERTIFICATED aircraft WITHOUT the STC is going to invoke the wrath of the FAA, not GAMI.  Unapproved modification. Period.

EAB is on their own although if 'bad things happen' the FAA will go after them for failing to adequately test the fuel.

All IMHO

[varlajo]

26 minutes ago, MikeOH said:

Your contract is with the fuel vendor, NOT GAMI.

Exactly. When you buy a Glock, you do not establish a relationship with Glock, but rather with the gun store and with your state's bureaucracy. Your sheriff might have something to say about it, but not the Austrians..