G100UL - fuel leak

[ragedracer1977]

2 hours ago, Pinecone said:

The difference is that many engines CANNOT run MOGAS with or without an STC.

G100UL can be used in ALL piston aircraft with an STC.

Except helicopters.  They’re all grounded.

why couldn’t I run mogas in an IO-520?

Oh.. wait. You can. With an STC. 

 Why can’t they use the inpulse as an example to ban 100LL?

The “with an STC” is the sticky wicket, IMO.  To be truly commercially available it needs to be drop in.  If I flew into CA - after they ban 100LL - without the STC, my plane is grounded until I buy the STC, wait for the placards to be delivered, and find an IA to sign a 337.  That could be weeks.  Thats not commercially available.

[MikeOH]

2 minutes ago, GeeBee said:

How much of the piston fleet is actually involved in air carrier operations. Very little. We are an ant on the butt of an elephant. 
 

My point about the airlines is even if you fast tracked TEL production getting a plant up and running with all the labor, material and manufacturing shortages it is unlikely anything would happen fast. Look up when the last new refinery was built. A friend of mine cannot find titanium right now at any pricr. All prodois committed. Airlined rigjt now have brand new airplanes sitting around for lack of spares and are pulling old airplanes out of the desert

Not sure why you're hung up on airlines???  GA piston aircraft serve far more than merely what the airlines use them for.  Many parts of our economy depend on GA piston aircraft. Not sure what 'fast' is, but if the GA piston fleet was going to grounded (the TEL plant goes offline tomorrow) I suspect there'd be another source of TEL before we ran out of whatever stockpiles of avgas exist.

[Ibra]

1 hour ago, PT20J said:

I read somewhere that the one in the UK was the only supplier for avgas. Maybe that was wrong, or maybe on one wants to deal with the other two.

Yes it's only factory that produce TEL and handle transport licences when it's used as fuel additive (my understanding anyone can produce it as the process is "simple" but not many outfits have paperwork to export and transport. Apparently, the TEL factory in India can't export for say 100LL in America or Europe)

https://innospec.com/

In Europe, Shell Netherlands is the main 100LL producer: they managed to secure an extension of approval to handle TEL in refineries until 2032 (Warter are expecting approval this month)

https://echa.europa.eu/en/applications-for-authorisation-previous-consultations?diss=false&search_criteria_ecnumber=201-075-4&search_criteria_casnumber=78-00-2&search_criteria_name=Tetraethyllead

 

 

 

 

Edited yesterday at 01:03 AM by Ibra

[GeeBee]

7 minutes ago, MikeOH said:

Not sure why you're hung up on airlines???  GA piston aircraft serve far more than merely what the airlines use them for.  Many parts of our economy depend on GA piston aircraft. Not sure what 'fast' is, but if the GA piston fleet was going to grounded (the TEL plant goes offline tomorrow) I suspect there'd be another source of TEL before we ran out of whatever stockpiles of avgas exist.

Only because airlines the first to show supplychain issues with high level manufacturing which is what is required tobuild a TEL plant

[MikeOH]

1 minute ago, GeeBee said:

Only because airlines the first to show supplychain issues with high level manufacturing which is what is required tobuild a TEL plant

I don't think either one of us really knows how 'difficult' it is to actually 'build' a TEL plant.  I didn't think the volume of product was all that high; i.e. not on the scale of an oil refinery.

But it's kind of moot because it's starting to appear that there are OTHER plants making TEL...so, we would really just be dealing with a permit/transport authorization issue.  Those bureaucratic hurdles would melt away before the US would let 100LL disappear.

[George Braly]

On 12/20/2024 at 9:02 AM, redbaron1982 said:

By the way, Swift was already aware of the issues that G100UL generates with paints and coatings:

Does Swift Fuels allow G100UL to be mixed with Swift Fuels UL94 or 100R in an approved piston aircraft?

No. G100UL must not be used at this time in aircraft approved for a Swift Fuels STC, and furthermore G100UL must not be intermixed with any Swift Fuels’ avgas product in any aircraft. This is because G100UL contains an aromatic amine “meta-toluidine” – an aggressive solvent that smells like turpentine – that testing shows is particularly prone to damaging paint/coatings, sealants, bladders, diaphragms, and various elastomeric parts in aircraft fuels systems. 

Ah...   G100UL is fully approved (by the FAA) to be mixed in any combination with ASTM UL94 (the fuel made by Swift) - - so long as the mixture of the two fuels is used in an engine and airplane already approved for use of UL94.   Swift can state whatever they want - - but that statement remains true. 

Observation:  It is likely true that if the fuel used at UND had as little as 20% G100UL avgas  (or 100LL) mixed in with the UL94 they were using - - then they would NOT have had the excessive valve seat erosion / wear that they documented.  That observation is based on the hard engine test stand data we presented at the G100UL forum last Oshkosh.  

[George Braly]

On 12/20/2024 at 4:23 PM, ragedracer1977 said:

 After reading the consent decree, I don’t believe G100UL is ‘commercially available’ per the wording the CEH themselves crafted.

See this snippet about mogas and explain how G100UL is different.

“The Parties acknowledge that certain aircraft that have obtained Supplemental Type Certificates from the FAA are permitted by law to use high octane automotive gasoline that does not contain lead ("Mogas"). Although some aircraft are capable of using Mogas, some are not. As a result, FBOs cannot offer Mogas in lieu of Avgas but only in addition to Avgas.”

 Since 90+% of the fleet is not currently capable of using G100UL, and 100% of piston helicopters would be grounded - how is different from mogas or UL94 in terms of the decree?

i tried to have this question answered on BT, but it was deflected and or I was just being a troll.

 

100% of all spark ignition piston engines are approved to use G100UL Avgas.

100% of all airplanes that use spark ignition piston engines are approved to use G100UL Avgas.

~ 98.5% of all AIRCRAFT are approved to use G100UL Avgas.  

The operative language is in the congressional reauthorization bill.  It states if the FAA has approved the fuel for use in "nearly all aircraft..."   Normally, Congressional language interpretation of that phrase means " more than 90%." 

The rotorcraft approval is pending.  It should have already been done, but there was an unexpected delay triggered by some unexpected "FAA" activity. 

[Marc_B]

On 12/19/2024 at 4:27 PM, Fly Boomer said:

I thought George was suggesting that UL might not be as hard on paint as LL based on the toluene percentage?

That's what was implied, but toluene isn't the only aromatic in aviation fuel.  "Low boiling aromatics, which are common constituents of aviation gasolines, are known to affect elastomers to a greater extent than other components in aviation gasoline."

In place of lead, G100UL uses increased amounts of aromatics (predominantly xylene, but also uses toluene and others) for octane.  Unfortunately, for proprietary reasons, the composition of this fuel isn't shared openly or with it's users.  Production Detail Hydrocarbon Analysis results are just listed as "Satisfactory" if it conforms to GAMI's standard and it doesn't appear these are shared with distributors, FBOs or end users. 

Mr. Braly's comment was also made with an example of 29% toluene from 2010, but my question is does this reflect current 100LL available at the pump?

If overall aromatic concentration in G100UL is higher than 100LL, how does this affect seals/sealant/paint in the short term and over the life of an airframe?  I think Mr. Braly is asking us to make a comparison that I don't feel we've been given enough detail to actually understand.

On 12/19/2024 at 4:37 PM, Pinecone said:

And it is not a beta, test, that level has been done. 

GAMI performed limited testing in development.  But there has not been extensive airframe testing across the fleet in vivo that covers the wide range of airframes and equipment, in the complete range of standard engine use in practice, and with older equipment with a variety of construction and maintenance over the years.  We’ve also not seen any longitudinal tests over engine TBO or life. Perhaps for clarity instead of saying "Beta" testing, the more specific term is "end-user testing."