AOPA President Flies On New Unleaded Fuel

FPK1

FPK1

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FPK1
Gami and AOPA to the rescue! Actually, I have a lot of respect for Gami and what they have accomplished with G100UL.

But here is another reason why I have lost respect for AOPA. Didn't Gami test for 10 years? Not sure this AOPA test is anything more than a waste of our dues:

generalaviationnews.com

AOPA president flies on new unleaded fuel — General Aviation News

AOPA President Mark Baker flew the Baron for one hour with G100UL feeding the left engine and 100LL in the right. He said the performance of the two engines was nearly identical and "the Baron flew beautifully."
generalaviationnews.com generalaviationnews.com
 
If someone needed AOPA's demo to be convinced...

SMH
 
Sounds more like a confirmation that this stuff (100UL) will be fine.

While the fuel has been the big worry, the old engines without hardened valve seats have been the biggest question. Can the valve seats and valves themselves survive on unleaded?

Remember when leaded automotive fuel went away? Same worry.
 
Zeldman said:
While the fuel has been the big worry, the old engines without hardened valve seats have been the biggest question. Can the valve seats and valves themselves survive on unleaded?

Remember when leaded automotive fuel went away? Same worry.
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One would think that OEMs would have been proactive on this and would have updated their engines to use materials that are suitable for unleaded fuels decades ago, particularly since the handwriting has been on the wall for a long time now that unleaded fuels were inevitable. Lycoming even went as far as approving most of their engines for various unleaded fuels about a decade ago.

Alas, it appears that the OEMs haven’t learned anything, assuming that the UND unleaded experiment is valid. But even if the OEMs do have engines that will withstand unleaded fuel use the PMA parts suppliers may be producing cylinders and other engine components that may not withstand it. I expect that we will have a rough road ahead when unleaded fuel is forced on us. Some problems will be real and manufacturers will hopefully respond accordingly.
 
As in the automotive world, retooling for hardened valve/valve seats in airplane engines all boils down to $$$ and the reluctance to spend.
 
AOPA president gets paid $1.5M per year to come up with creative ways to have fun, while writing it off as a business expense and calling it a service to its members. Unbelievable that the members just keep supporting this. I wish we had actual representation and would happily pay even more in dues. They waste $50M per year. So frustrating.
 
Zeldman said:
As in the automotive world, retooling for hardened valve/valve seats in airplane engines all boils down to $$$ and the reluctance to spend.
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Take a look at BMW’s early 80s experience in this regard. Their first try on motorcycle engines was a complete technical failure, with new hardened valve seats the problem was much worse than for previous engines. The hardened seat material conducted heat away from the valves worse, so the hotter valves recessed like crazy. They got it right the second time, circa 1984. Apparently not so simple, although by now there’s a lot more industry experience.
 
Zeldman said:
While the fuel has been the big worry, the old engines without hardened valve seats have been the biggest question. Can the valve seats and valves themselves survive on unleaded?
Click to expand...

I'd like to hear @Martin Pauly weigh in on this. I'd be pretty surprised if George hasn't considered and addressed this concern.
 
Half Fast said:
I'd like to hear @Martin Pauly weigh in on this. I'd be pretty surprised if George hasn't considered and addressed this concern.
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I haven't heard George talk to the issue which UND raised after their UL94 trial, specifically what may have caused the valve recession. Was it the lack of lead? Was it the lower octane rating? Was it something entirely different?

What I do know is GAMI has been running their turbo-normalized SR-22 with G100UL for many years, apparently to their full satisfaction. There were other longevity tests run on different engines as part of the fuel certification test program. Very few certification programs have had as much FAA oversight as G100UL (maybe short of the Boeing 737MAX), so I am willing to bet that this has been looked at. George does speak at aviation events every now and then - this would be a good question to ask him directly.

I do remember George and the other APS guys answer a question about lead during the APS seminar, maybe ten years ago. Research on unleaded fuel was already underway, and the question from a seminar participant was whether the lead in 100LL provided lubrication. The answer was an emphatic 'no', along with a chemical rationale for their position which was over my head.

By the way, there is a thread over on BeechTalk about the same topic where George might address this question.

- Martin
 
Valve seat recession could be an issue with some engines, nobody seems to know for sure exactly which ones. For many years Petersen has had STCs to run unleaded gas in many of the popular lower performance engines like the O-320 and O-360. Some of those STCs (for example with high wing gravity fed fuel systems) are paperwork only, no modifications needed. This suggests that valve recession shouldn't be a problem with these engines.
 
MRC01 said:
Valve seat recession could be an issue with some engines, nobody seems to know for sure exactly which ones. For many years Petersen has had STCs to run unleaded gas in many of the popular lower performance engines like the O-320 and O-360. Some of those STCs (for example with high wing gravity fed fuel systems) are paperwork only, no modifications needed. This suggests that valve recession shouldn't be a problem with these engines.
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Last I checked, both of the common autofuel STCs recommend engine/cylinder break in on leaded fuel. There is a reason for this; many engines that were initially run on leaded fuel will have no trouble running unleaded after the initial run in but if the initial run in was done on unleaded the recession may be excessive. In other words, I don't think the folks running autofuel are a great test to prove that the transition to unleaded fuels will have no long term effects.
 
MountainDude said:
AOPA president gets paid $1.5M per year to come up with creative ways to have fun, while writing it off as a business expense and calling it a service to its members. Unbelievable that the members just keep supporting this. I wish we had actual representation and would happily pay even more in dues. They waste $50M per year. So frustrating.
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Can't really argue too much here. Not to mention the money they have in the bank to help with medical reform and other more important issues that lay idol.
 
What was the last thing he did for fun?

I left just before the wine club hullaballoo. Haven't missed the mag. They never gave me the promised hat last time I upped.
 
Our O200 seems to run best on %25 100LL and %75 unleaded Mogas.

I haven't run the numbers to see if that's close to the old 80/87.
 
schmookeeg said:
What was the last thing he did for fun?

I left just before the wine club hullaballoo. Haven't missed the mag. They never gave me the promised hat last time I upped.
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Was it when he took the grand champion award himself for his seaplane at last year's OSH?
 
RyanB said:
Hang on, let me debunk that - the students couldn’t have cared less what fuel the airplanes ran on.
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Students like lower costs and that is what UND was attempting.

“Fueling UND aircraft with UL94 will help UND Aerospace avoid maintenance issues that occur when using leaded avgas, which fouls aircraft engines with lead deposits. The new fuel will extend the interval between oil changes and reduce the frequency of spark plug replacements and other mechanical issues and delays that interrupt a flight schedule.

Kasowski said switching to the new unleaded avgas will allow UND to increase the required maintenance inspection interval for its aircraft by 25%. In 2022, UND Aerospace Aircraft Technicians performed 1,432 mandated aircraft inspections. The new fuel could potentially reduce the number of those inspections by about 270 per year.

“Fewer aircraft inspections per year will mean less aircraft down time, resulting in improved aircraft availability for flight training, and reduced maintenance costs,” Kasowski said. “We also anticipate reduced costs for spark plugs, oil, filters and internal engine parts.””

Just because the UND flight school experienced increased valve issues when they switched fuel doesn’t mean the fuel was the cause. Young CFIs are rather stupid when it comes to proper leaning procedures.
 
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Clip4 said:
Students like lower costs and that is what UND was attempting.

“Fueling UND aircraft with UL94 will help UND Aerospace avoid maintenance issues that occur when using leaded avgas, which fouls aircraft engines with lead deposits. The new fuel will extend the interval between oil changes and reduce the frequency of spark plug replacements and other mechanical issues and delays that interrupt a flight schedule.

Kasowski said switching to the new unleaded avgas will allow UND to increase the required maintenance inspection interval for its aircraft by 25%. In 2022, UND Aerospace Aircraft Technicians performed 1,432 mandated aircraft inspections. The new fuel could potentially reduce the number of those inspections by about 270 per year.

“Fewer aircraft inspections per year will mean less aircraft down time, resulting in improved aircraft availability for flight training, and reduced maintenance costs,” Kasowski said. “We also anticipate reduced costs for spark plugs, oil, filters and internal engine parts.””

Just because the UND flight school experienced increased valve issues when they switched fuel doesn’t mean the fuel was the cause. Young CFIs are rather stupid when it comes to proper leaning procedures.
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And I doubt they were planning on 125 hours between 100-hour inspections, so most likely students and young CFIs were mismanaging the engines to the point of increased maintenance to start with.
 
MauleSkinner said:
And I doubt they were planning on 125 hours between 100-hour inspections, so most likely students and young CFIs were mismanaging the engines to the point of increased maintenance to start with.
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You only need one idiot CFI doing dumb stuff in an fuel injected Archer to damage a bunch of valves in a week or 2.
 
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