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Posted
1 hour ago, Fly Boomer said:

Eventually, someone will run their gas, and then we shall see.

I still think it’s going to take significant time, and a fleet of aircraft in the great white north and the heat of Arizona etc., and all other conditions, high altitudes etc.

‘My concern is LL will be outlawed, then we will have no choice, without competition the possibility of price gouging exists, As I understand it George will have no control over pricing.

Sometimes it takes odd combinations of environmental conditions, operation techniques etc. for things to surface.

I wasn’t flying GA at the time, but the Mobil 1 oil I’m sure passed all FAA required tests and how many airplanes had to run it for how long before problems surfaced? Just to use it as an example.

  • Like 2
Posted
2 hours ago, Rick Junkin said:

This will likely prove to be a red herring but it’s out there. AOPA left their dual fuel Baron at OSH due to stains discovered under the wing with G100UL in it. Lots of interesting speculation but no reliable data yet. Read the comments.

https://www.avweb.com/aviation-news/stains-on-aopa-baron-wing-to-be-checked-by-mechanic/

At the event I attended at the Buckeye Air Fair, George essentialy said that G100UL is a stronger solvent than 100LL, to not let it get on your paint for very long, etc., etc.   I suspect that one of the (potentially many) reasons that the manufacturers (and others) are hesistant to take a position is that the long-term effect on sealants, seals, gaskets, and other materials is unknown.   It's been discussed here before that one of the things this affects is the distributor's ability to insure liability in the distribution and vending stream.   Our local fuel vendor brought this up at a meeting as one of the current barriers to adoption of G100UL.

So the tank leak might be a result of that.

  • Like 3
Posted

If it was a Baron, pretty sure it has bladders.

But many things will deteriorate fuel tank sealer, we used it inside the hopper of the Thrush as a sealant where the Stainless Steel braces etc were inside the fiberglass hopper. Something that crop dusters put inside the tank eats fuel tank sealant over time and it has to be re-sealed every couple of years. I don’t know what they put in the hopper that ate sealant, but something does, and most things crop duster carry is heavily water based.

Earlier in the thread I posted a pic from my IA renewal where one bladder manufacturer said the aeromatics significantly reduce the life span of bladders. 

Posted
10 hours ago, M20F said:

If you were an engine manufacturer why would you, what benefit is there?  What risks do you expose yourself to?

Long term business viability. If you have a captive customer base, not being customer friendly will work - but only for a while. Long term, the business will die. 

Posted
7 hours ago, hais said:

Long term business viability. If you have a captive customer base, not being customer friendly will work - but only for a while. Long term, the business will die. 

100LL is still readily available in most states. There is no benefit to be gained by the engine manufacturers to enter the fray.

As I understand it most aero engines were certified to run on fuels that meet a specific ASTM standard. In most cases, those standards specify TEL as an antiknock. 
 

this means the engines must either recertify to a new ASTM standard that does not contain TEL but meets minimum octane requirements (does not currently exist ) or the fuel must be approved through STC.

It’s not so simple as an engine manufacturer endorsing a fuel producer. 

  • Like 2
Posted
13 hours ago, A64Pilot said:

burning race gas detonation just wasn’t an issue like it is on normal fuel.

All E85 all day, vroom vroom.  

  • Like 2
Posted
3 hours ago, Shadrach said:

As I understand it most aero engines were certified to run on fuels that meet a specific ASTM standard. In most cases, those standards specify TEL as an antiknock. 
 

this means the engines must either recertify to a new ASTM standard that does not contain TEL but meets minimum octane requirements (does not currently exist ) or the fuel must be approved through STC.

It’s not so simple as an engine manufacturer endorsing a fuel producer. 

The standard is ASTM D910.   I have a copy of -11 which is from 2011, but they're up to -21 now.   It's unusual for a standard to specify how to do something, just what characteristics the item must have.    In this case the Octane numbers and anti-knock values are specified, and maximum levels of TEL (so that it doesn't exceed environmental and other requirements) are specified.   If a fuel can meet all of the other requirements with less or no lead (TEL), it isn't required.   The only TEL requirement is that it not exceed specified amounts.

Posted
On 8/1/2024 at 8:59 AM, GeeBee said:

As to his data, it was ran through two FAA offices independently. Wichita and Atlanta. Both witnessed, both signed off as complete and rigorous. It is tough to attack his methodology when the FAA admits his lab and methods are better than theirs. GAMI's lab is considered the finest in the world. I don't know what else has to be done but the data set looks to be stellar. 

Not trying to knock on GAMI, but I'm not sure how much trust is gained by having the FAA look at the data GAMI supplied. We've seen how well that works with Boeing.

The ignition timing issue can be resolved for most of the fleet with variable timing. Ignitions systems have come a LONG way.

  • Like 1
Posted

….
The ignition timing issue can be resolved for most of the fleet with variable timing. Ignitions systems have come a LONG way.

The only solution is a drop in fuel replacement.
There is no ignition timing issue in the eyes of the engine manufacturers nor most owners for that matter. Nobody wants to decrease their engine horsepower even if it was available.


Sent from my iPhone using Tapatalk
  • Like 4
Posted (edited)
4 hours ago, Shadrach said:

As I understand it most aero engines were certified to run on fuels that meet a specific ASTM standard. In most cases, those standards specify TEL as an antiknock. 

There are two standards one for low lead Avgas and the other for unleaded Avgas 

* ASTM D910: Standard Specification for Aviation Gasolines

* ASTM D7547: Standard Specification for Unleaded Aviation Gasoline 

G100UL would fall under D7547 which would require working with engine manufacturers and avgas producers, however, GAMI chose to go down STC route with FAA

UL91 from Total and 91/96UL from Hjelmeco are ASTM for unleaded fuel (I don't think it's sold in US), in Europe, they are certified for airframe if engine manufacturers have them on the list (blanket signoff), in US aircraft, I think they need STC like UL94? 

The UL91 and 91/96UL are not ASTM D7547, however, they fall under something similar DEF-STAN for unleaded Avgas 

Edited by Ibra
Posted
1 minute ago, Ibra said:

UL91 from Total ans 91/96UL from Hjelmeco are ASTM for unleaded fuel (I don't think it's sold in US), in Europe, they are certified for airframe if engine manufacturers have them on the list (blanket signoff), in US aircraft, I think they need STC like UL94? 

The UL91 and 91/96UL are not ASTM D7547 but they fall under something similar DEF-STAN for unleaded Avgas 

The TCDS for most of the earlier Mooneys says, "100LL or 100/130 octane minimum grade aviation gasoline".

For some of the later ones it says, "Fuel 100 LL or 100 min-grade aviation gasoline".

Anything that meets those won't need an STC and would be genuinely drop-in.    There's no definition or standard specified in the TCDS, so I've always figured whatever it says on the dispensing tank would be a reasonable field interpretation as far as "minumum grade" goes.

 

  • Like 1
Posted (edited)
32 minutes ago, EricJ said:

The TCDS for most of the earlier Mooneys says, "100LL or 100/130 octane minimum grade aviation gasoline".

The older TCDS referred to min octane grades "avgas" without talking about standards

It's later TCDS that explicitly refer to Lyco approved fuels (e.g. SI1070), these gave more control to engine manufacturers to stick ASTM or DEF-STAN label on Avgas 

https://www.lycoming.com/service-instruction-no-1070-AB

 

 

 

 

Edited by Ibra
  • Like 1
Posted
7 minutes ago, Ibra said:

The older TCDS referred to min octane grades "avgas" without talking about standards

It's later TCDS that explicitly refer to Lyco approved fuels (e.g. SI1070), these gave more control to engine manufacturers to stick ASTM or DEF-STAN label on Avgas 

https://www.lycoming.com/service-instruction-no-1070-AB

The latest rev for the Mooney TCDS 2A3 is 58, which is the one I was referencing.    The airframe TCDS supercedes the engine TCDS, so it drives in determining what can go in the tank, placards, etc.

And the Lycoming SI1070 is a very good reference as well.   There are definitely more than one standard when it comes to most things.

 

  • Like 1
Posted
4 hours ago, Paul Thomas said:

Not trying to knock on GAMI, but I'm not sure how much trust is gained by having the FAA look at the data GAMI supplied. We've seen how well that works with Boeing.

The ignition timing issue can be resolved for most of the fleet with variable timing. Ignitions systems have come a LONG way.

That was why it was ran through two separate FAA offices, Wichita and Atlanta. After Wichita signed off, the FAA said, "Let's have a second look to insure nothing was missed" and turned to the Atlanta office. They did so specifically saying they did not want a repeat of the 737 MAX debacle. So GAMI essentially went through two separate certifications when it was really only required to pass Wichita. GAMI could have went to court, but instead, had faith in their product and process to double down and prove their data and the viability of their product agin.

We complain about the price of things for aviation and yet we assail people when someone fulfills all the requirements. Other than opening up a vein and and handing over his first born child, I don't know what more is to done to achieve certification. If you nay sayers have thought please place it here, specially if not, general innuendo is just that, innuendo. 

  • Like 1
Posted
18 minutes ago, GeeBee said:

We complain about the price of things for aviation and yet we assail people when someone fulfills all the requirements. Other than opening up a vein and and handing over his first born child, I don't know what more is to done to achieve certification. If you nay sayers have thought please place it here, specially if not, general innuendo is just that, innuendo. 

Be careful there, your bias to accept a new product just because you like Braly is showing.  Not to mention confusing justified skepticism with innuendo in an attempt to silence dissenters.

I have a few factual reasons that I'm not ready to become a GAMI fan-boy:

1) GAMI would have a monopoly if 100LL was banned. We need at least one other approved alternate before this issue goes away.

2) NOT ASTM approved. Sorry, but I'm not as comfortable as fan-boys with simply ignoring Lycoming's warning that GAMI use may invalidate warranty.  Talk about innuendo: vilifying Lycoming for being financially prudent!

3) GAMI's data is one-sided and limited to ONLY what the FAA requires. No way there is no downside; engineering is the art and science of balancing trade-offs.  We just aren't privy to the downsides.  And, some of those may not become apparent until many years AFTER the fleet starts using the fuel.

4) It's going to be more expensive.  See item 1, which will at least limit the carnage!

OPINION wise, this entire ban 100LL 'project' is over blown.  However, I'm a realist and know it is inevitable. It's the idea that we will be forced to be 'beta testers'.  No amount of 'lab' testing, regardless if it's done in the "world's best test chamber" is going to replace real world testing. And, sorry but running ONE twin engine plane for several hundred hours isn't convincing data. Nor is two or three. TIME (calendar and hours) on the scale of years and 10,000s of hours is going to be needed.  To ban a known proven fuel, 100LL, and force us to purchase higher priced GAMI fuel before it's proven in the field is risky. Yeah, in MY opinion.

  • Like 2
Posted

I have been reading a lot of aviation history, particularly in the post-war era. Did you know the first 5 production 707s all crashed due to dutch roll problems? Heck, Braniff with a Boeing instructor pilot managed to tear off 3 out of 4 engines and crash the airplane. The L-188 Electra had 6 crashes in 31 months. The Boeing 377 StratoCruiser was crashing faster than Boeing could build them. By the time production ended, more crashed than had survived. I have not even covered the vertical stab problems on the B-52 or the fuel leaks on the B-36.  If we applied the current standard for design integrity as in the B737Max, the 707, the 727, the L-188, 377 StartoCruiser, the DC-6, DC-7 and the 049 Constellation all would have been on the scrap heap of history. In GA terms, the C-177, Rockwell 112, Bonanza et al would also be in the same boat, scrapped designs. But their problems in fleet operations were noted and worked out. 

While I am not happy about it, George Braley was correct by not going ASTM because it is a "consensus standard" and there are too many people with axes to grind to get a consensus. There will never be a "consensus standard" 100UL fuel until there is a a fuel out in the fleet being flown and that is what Braley is trying to get done. Yeah, we are all going to be test pilots, but I dare say there will be fewer accidents for G100UL than from other forms of fuel contamination like water and crud in the fuel. 

The bottom line is GAMI's plan is using the inevitable ban on 100LL to force their fuel into the fleet for fleet operations. Because of their patents and testing ability they are the last man standing. I would be very surprised if the current formulation continues on without tweaks but the bottom line is we will never know without widespread use, and we will never get an ASTM "consensus" until those with axes to grind are left without a grinding wheel. We are left with two choices, having airplanes without a suitable fuel by those who wish us ill or we get on with fleet wide operations of the best options available and accept a small level of risk. I consider the risk eminently manageable. We may have a few material incompatibilities here and there, we may see some engines, not all but some have valve problems. I don't see anybody falling out of the air in any airplane given proper maintenance scrutiny operating with this fuel.  I say, let's get on with it and solve the problem, sooner rather than later.

  • Like 3
Posted
12 hours ago, Shadrach said:

100LL is still readily available in most states. There is no benefit to be gained by the engine manufacturers to enter the fray.

As I understand it most aero engines were certified to run on fuels that meet a specific ASTM standard. In most cases, those standards specify TEL as an antiknock. 
 

this means the engines must either recertify to a new ASTM standard that does not contain TEL but meets minimum octane requirements (does not currently exist ) or the fuel must be approved through STC.

It’s not so simple as an engine manufacturer endorsing a fuel producer. 

I'm not sure what "endorsing" entails, but, there's an STC, someone has done lots of testing. If there's a will to read the market, and the bulk of the work was already done, why wouldn't you? Understandable if one is exiting the market. I suspect they will make an interesting case study in business schools sometimes in the future. 

Posted
22 hours ago, M20F said:

All E85 all day, vroom vroom.  

Ethanol can cause some interesting problems itself.

I used to race Spec Racer Ford, Gen II car.  Early 80s Ford Escort GT engine.  Ran well for many years running pump regular fuel (87 AKI).   Then, all of a sudden the class was braking pistons.  The part between the top ring and the piston head would break off.

So we switched to pump premium (93 AKI).  No change, still had issues.  Switched to ethanol free, race 93 AKI fuel and no more problems.   

Posted
15 hours ago, MikeOH said:

Be careful there, your bias to accept a new product just because you like Braly is showing.  Not to mention confusing justified skepticism with innuendo in an attempt to silence dissenters.

I have a few factual reasons that I'm not ready to become a GAMI fan-boy:

1) GAMI would have a monopoly if 100LL was banned. We need at least one other approved alternate before this issue goes away.

2) NOT ASTM approved. Sorry, but I'm not as comfortable as fan-boys with simply ignoring Lycoming's warning that GAMI use may invalidate warranty.  Talk about innuendo: vilifying Lycoming for being financially prudent!

3) GAMI's data is one-sided and limited to ONLY what the FAA requires. No way there is no downside; engineering is the art and science of balancing trade-offs.  We just aren't privy to the downsides.  And, some of those may not become apparent until many years AFTER the fleet starts using the fuel.

4) It's going to be more expensive.  See item 1, which will at least limit the carnage!

OPINION wise, this entire ban 100LL 'project' is over blown.  However, I'm a realist and know it is inevitable. It's the idea that we will be forced to be 'beta testers'.  No amount of 'lab' testing, regardless if it's done in the "world's best test chamber" is going to replace real world testing. And, sorry but running ONE twin engine plane for several hundred hours isn't convincing data. Nor is two or three. TIME (calendar and hours) on the scale of years and 10,000s of hours is going to be needed.  To ban a known proven fuel, 100LL, and force us to purchase higher priced GAMI fuel before it's proven in the field is risky. Yeah, in MY opinion.

1)  GAMI does NOT make fuel.  They license a formula to ANYONE who want to make it.  Right now, there are 4 US refineries making 100LL.  With G100UL, anyone can buy the ingredients and blend it.

2)  ASTM does NOT approve anything.  ASTM publishes a standard that you can follow to say your product meets ASTM Standard XYZ.  It doesn't mean ANYTHING else..  There could be an ASTM standard for Irish Coffee.  And all that would mean is that if you make it in accordance to the standard, you could advertise your Irish Coffee is made to the ASTM standard.  That doesn't mean it will taste good.

3)  Read the history, GAMI has gone above and beyond the level of testing when 100LL was developed.  

4)  Maybe.  The profit per gallon of AVGAS is higher than for MOGAS.  Since you don't need special equipment and handling to deal with potential lead contamination, anyone can blend it.  So more people making is is more competition, which can lead to lower prices.  Also, one large component of the cost of AVGAS is transportation costs.  Right now, my home field has to get 100LL from over 250 miles away.  I think I heard that the rate is around $4 per mile.  And the tanker has to go back.  So $2000 added to the cost of the fuel.  If a closer refinery is blending G100UL, it would be in the tank at the FBO for not much more than 100LL being trucked that far.

5)  GAMI has been FLYING G100UL for many years in many different airplanes.  The Baron you are talking about is being done by AOPA, NOT GAMI.  And it not a "test" of the fuel, it is a public demo of a fuel that has been well tested.

  • Like 3
Posted
1 hour ago, Pinecone said:

Ethanol can cause some interesting problems itself.

I used to race Spec Racer Ford, Gen II car.  Early 80s Ford Escort GT engine.  Ran well for many years running pump regular fuel (87 AKI).   Then, all of a sudden the class was braking pistons.  The part between the top ring and the piston head would break off.

So we switched to pump premium (93 AKI).  No change, still had issues.  Switched to ethanol free, race 93 AKI fuel and no more problems.   

Yeah you ought to see what ethanol fuel does in marine applications. In particular boats with fiberglass tanks. They became tanks of goo and did you know ethanol fuel starts "phase separation" after about 30 days? Go to any marine store and you will see several brands of "ethanol fuel stabilizers". I am fortunate in that all the marinas and some gas stations in my area sell non-ethanol 90 octane. I wince when I see a boat on a trailer filling up at Costco. He will be in the maintenance shop in short order. Same problems with outdoor power equipment which is why they sell "True Fuel" at Home Depot.

Posted
On 8/4/2024 at 4:30 PM, MikeOH said:

Be careful there, your bias to accept a new product just because you like Braly is showing.  Not to mention confusing justified skepticism with innuendo in an attempt to silence dissenters.

I have a few factual reasons that I'm not ready to become a GAMI fan-boy:

1) GAMI would have a monopoly if 100LL was banned. We need at least one other approved alternate before this issue goes away.

2) NOT ASTM approved. Sorry, but I'm not as comfortable as fan-boys with simply ignoring Lycoming's warning that GAMI use may invalidate warranty.  Talk about innuendo: vilifying Lycoming for being financially prudent!

3) GAMI's data is one-sided and limited to ONLY what the FAA requires. No way there is no downside; engineering is the art and science of balancing trade-offs.  We just aren't privy to the downsides.  And, some of those may not become apparent until many years AFTER the fleet starts using the fuel.

4) It's going to be more expensive.  See item 1, which will at least limit the carnage!

OPINION wise, this entire ban 100LL 'project' is over blown.  However, I'm a realist and know it is inevitable. It's the idea that we will be forced to be 'beta testers'.  No amount of 'lab' testing, regardless if it's done in the "world's best test chamber" is going to replace real world testing. And, sorry but running ONE twin engine plane for several hundred hours isn't convincing data. Nor is two or three. TIME (calendar and hours) on the scale of years and 10,000s of hours is going to be needed.  To ban a known proven fuel, 100LL, and force us to purchase higher priced GAMI fuel before it's proven in the field is risky. Yeah, in MY opinion.

BDS is real…

I don’t think 100LL is a significant environmental issue. However, the writing is on the wall… 100LL’s days/years are numbered, especially since those who seek to ban it will be minimally affected by its absence (e.g. non flying public and politicians who prefer to burn tax payer purchased jet-A).

It’s not GAMI’s fault that they have what appears to be the only currently viable “drop in” thus far. I am sure George had his reasons for going the STC route. I don’t know what they were, but my guess is it had to do with politics and process. Why else would he bother to go through the STC certification process twice rather than work within the PAFI framework. Good for him for going his own way. He still has a tough row to hoe. I won’t be buying an STC unless/until G100UL is readily available in my geographic area.

Do remember that any company that crossed the finish line 1st would be in GAMI’s situation. It’s not like some dark, insidious force is pushing for their monopoly. It’s simply a function of a small, agile, firm grabbing the ring first.  I’m all for competition. Unfortunately, UL94 clearly has issues…unless you think George Braly and his evil minions sabotaged the UND trial. Given that 94 UL has failed to meet expectations. I’m pretty dubious that they’re going to get to 100 in the near future.

Being that you’re in “Kalifornia”, as you’re fond of saying, I hope you have alternative plans for your airplane because there’s more pressure in your area than anywhere else in the country to prevent you from purchasing 100LL.

It’s odd that you have no gratitude for the fact that someone has actually taken the risk, effort, investment and time required to develop an unleaded Aviation fuel that is likely turnkey in your current aircraft and also feel compelled to call those that do have gratitude, “fanboys”…

  • Like 4
Posted
4 hours ago, Pinecone said:

Ethanol can cause some interesting problems itself.

I used to race Spec Racer Ford, Gen II car.  Early 80s Ford Escort GT engine.  Ran well for many years running pump regular fuel (87 AKI).   Then, all of a sudden the class was braking pistons.  The part between the top ring and the piston head would break off.

So we switched to pump premium (93 AKI).  No change, still had issues.  Switched to ethanol free, race 93 AKI fuel and no more problems.   

E85 is 100-105 octane.  It is moonshine gas, not an ethanol additive to mogas.   If you are racing these days it is the way to go, crank that advance.

 

Posted
4 hours ago, Pinecone said:

The Baron you are talking about is being done by AOPA, NOT GAMI.  And it not a "test" of the fuel, it is a public demo of a fuel that has been well tested.

I'm assuming most people by now have seen the AVweb article on AOPA's Baron leaking bladder.  And how the bladder was supposed to be replaced before the G100UL test came around, but they couldn't get one.

https://www.avweb.com/aviation-news/aopa-baron-wing-stain-traced-to-leaking-bladder-patch/?MailingID=FLY240805003&utm_campaign=avwebflash&utm_medium=newsletter&oly_enc_id=6466I3042634F3A

Posted
1 hour ago, M20F said:

E85 is 100-105 octane.  It is moonshine gas, not an ethanol additive to mogas.   If you are racing these days it is the way to go, crank that advance.

 

How is E85 relevant to aviation? At 73% of the energy density of avgas by volume it does not seem like a viable option for low compression (relatively speaking), naturally aspirated engines, even with variable ignition timing.

100LL = 120,200 BTU per gallon

E85 = 88,358 BTU per gallon.

 

 

Posted
18 minutes ago, Shadrach said:

Hi is E85 relevant to aviation? 

No it was in response to auto racing (follow the thread), don’t be obtuse.  That being said till I am guessing about 10K you could get away with E85 in an airplane.
 
I could probably get another 20-30HP in the MG shifting to E85 but I am lazy.   

  • Like 1

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