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UNLEADED AVGAS Announcement

Utah-Jay

MEMBER
Heber City, UT
Should be huge news out of Oshkosh today that will be a big bonus and he says that there will not be a monopoly

 
Everyone understands that this is complete bull-hockey, right?

History...

73 octane, the fuel O-145s and A-40, 50, 65s were certified under contained 0.0 part per anything tetraethyl lead.

TEL was an additive to retard ignition-- creating so-called no-knock fuels.

80/87 had 0.10 parts per million TEL.

For reference 87 "UNLEADED" octane auto gas has 0.14 ppm, and 100LL aviation gas 1.4 ppm TEL.

Don't believe me? Check Wikipedia for starters-- there are better sources but this isn't an unknown.

So we bribe uncle to use fuel the plane was certified to use instead of an inappropriate one... Well, at least it's cheap, a dollar per horsepower.
 
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No matter what, the owner would need to purchase an STC for the engine and another STC for the engine, then get their IA to file 337s installing those STCs.

Like was stated above, we would have been better if back in the 70s they kept 80/87 and 100/130. The total lead used would have been less as the majority of ga airplanes could still use 80/87.

The fuel companies just didn’t want to stock two different fuels. If they didn’t want to carry multiple fuels then, I can’t see them offering multiple fuels now.


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Whatever the manner of achieving unleaded avgas, regulators will eventually demand it. Aviation is lumped in with 'nonroad engines', which also includes locomotives and marine engines. Fuel combustion includes fixed sources.

Nonroad engines are the largest remaining source of airborne lead.
 

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Thanks for the post. Here's an AOPA article for those of us that dislike watching talking heads:
https://www.aopa.org/news-and-media/all-news/2021/july/27/gami-receives-unleaded-avgas-stc
Such a deal! Now we will get the opportunity to buy some more STCs for the privilege of paying 60-85 cents more for a gallon of av-gas which is already expensive. :evil: I can see it now when pulling up to the gas pumps. "Do you want the no lead gas for $6 bucks a gallon or do you want the $5 fuel for your 15 gallon per hour airplane?" This will really promote general aviation.
 
Such a deal! Now we will get the opportunity to buy some more STCs for the privilege of paying 60-85 cents more for a gallon of av-gas which is already expensive. :evil: I can see it now when pulling up to the gas pumps. "Do you want the no lead gas for $6 bucks a gallon or do you want the $5 fuel for your 15 gallon per hour airplane?" This will really promote general aviation.

EXACTLY why I am a MoGas fan
 
Am I missing sumpthin' ? Gov't mandated but need an STC? How will that work at the pumps?
 
Braly said GAMI expects to begin selling STCs in the first half of 2022 but hasn’t set a price. The price of the fuel itself also hasn’t been determined.

So, pay a bunch for the STCs and pay a bunch for the fuel. And, it weighs more than avgas. Lovely.
 
All for a nonexistent public health issue. Lead poisoning from environmental lead has never made one person sick. Direct exposure, very rarely. Once the wheels of government begin to turn, they never stop.
 
The FAA bureaucrats kept throwing more hoops at GAMI so they went an easier route via STC. Sweden has had a substitute for many years.
 
Another benefit of Experimental IF the new fuel becomes mandated. Not that I know anything about this stuff, but not sure how the entire legacy engine fleet could be mandated to buy an STC.

It just seems to me that new aircraft engines should start joining the 21st century technology.

I am deep in the woods planning a build, sadly my engine of choice (Rotax 915) can not be used on the Bearhawk Companion for weight and balance reasons. The 915 is 113 pounds lighter than the -360 variants, produces more power at my elevation and DA’s and can use MoGas. I just find it amazing that we are stuck in the 1950’s in so many ways
 
I am deep in the woods planning a build, sadly my engine of choice (Rotax 915) can not be used on the Bearhawk Companion for weight and balance reasons. The 915 is 113 pounds lighter than the -360 variants, produces more power at my elevation and DA’s and can use MoGas.
SO? Do a weight and balance computation, build a longer engine mount and extend the cowl to match. What's the big deal?
 
SO? Do a weight and balance computation, build a longer engine mount and extend the cowl to match. What's the big deal?

That was my initial thought, but the designer said it was a no go on an engine that light. I think IF you did extend the engine mount it would be crazy long, FUGLY, and impossible to see forward at all
 
You would need to move the engine in the neighborhood of 30 inches ! and then we would need to think about how much lighter the prop is ??
 
It just seems to me that new aircraft engines should start joining the 21st century technology.

I am deep in the woods planning a build, sadly my engine of choice (Rotax 915) can not be used on the Bearhawk Companion for weight and balance reasons. The 915 is 113 pounds lighter than the -360 variants, produces more power at my elevation and DA’s and can use MoGas. I just find it amazing that we are stuck in the 1950’s in so many ways

I agree whole heartedly about the incomprehensible affinity for antique engines in aviation. Folks will buy a plastic airplane but only if it has an engine designed before WWII. I just don't understand.

That being said...

Use the Rotax and weld a counterweight on the engine mount. It will have the secondary benefit of somewhat damping engine vibration too. Win - win. That is IF weight isn't an issue. Just an idea.
 
Instead of building a long engine mount, you could always just way overbuild it at a more standard length, then use 16ga steel for your engine cowl... That oughta just about make it equal weight, lol.
 
Radiator, piping, water and all?

The Rotax engine weighs 187 from my understanding

Edited to add:
Mark Goldberg of AviPro who sells the BH kits said the 915 would not be possible on the BH Companion (2 seater side by side configuration) due to weight and balance (CG envelope) as it would be way too aft
 
The Rotax engine weighs 187 from my understanding

Edited to add:
Mark Goldberg of AviPro who sells the BH kits said the 915 would not be possible on the BH Companion (2 seater side by side configuration) due to weight and balance (CG envelope) as it would be way too aft
Don't forget the battery weight. Where is it now mounted? Place it next to the engine.
 
Radiator, piping, water and all?

Steve, most of what I’ve seen are wet installations of 200-210 pounds for the 915. It’s about 75-85 pounds lighter when installed vs the Titan O-340. 915 dyno’s at 145hp to 15,000ft. The Sling TSi made it to FL290 with it.
 
Rotax vs. Lycoming

Radiator, piping, water and all?

I think what isn't mentioned here is that the Rotax uses a much smaller prop which will result in much lower performance on a larger airplane. For example, a 220 Stearman hauls its heavy weight briskly into the air with a 108 inch McCauley steel prop. Put a shorter wood prop on it and it's a dog. Put a tiny prop on a Rotax powered Bearhawk, and I have serious doubts. Another example was the old OX-5 powered planes like the Waco 10 and, Lincoln Page and Brunner Winkle Bird. 90HP and carrying 3 people. They turned 1300 revs on a good day, according to my grandfather, but that long prop pulled them into the sky. I don't know of any Rotax powered planes that have big props. Great on a Rans, but it's a light machine, appropriate to the prop length and high revving engine.

As for the lead issue, .. please tell me where the Mayo Clinic report says anything at all about AvGas being a source of lead poisoning? Did they forget, or is it actually a non-issue. 100LL, yeah we all laughed when "high lead" LL100 came out. Only 4 times the lead of 80 octane. So full of lead they had to design new spark plugs for C-150's. Somebody had to come up with an answer to the California granola set, so good for GAMI. That said, you can bet they'll keep scratching and digging to shut us down. today I got a notice form SNG Barret, makers of parts for vintage Jaguars. The newly formed Alliance for Historic and Classic Vehicles is fighting against restrictions in Europe on operating and restoring old cars. That is coming our way as well, so we need to prepare. GAMI's work is a step in the right direction.

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The Norden is using an 80” 4 blade E-Props fixed pitch yielding 771 pounds of thrust with the 915 iS. Sure you won’t have the torque of the Titan but you’ll still win the power to weight ratio and performance above 5,000ft. 5DACAE12-75C0-48BE-B76B-23EE0E4BF8D8.jpeg
 

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...... I think IF you did extend the engine mount it would be crazy long, FUGLY, and impossible to see forward at all

Check out a Pilatus PC6 Porter sometime.
Long nose, & different looking, but what a performer.
AeroComp did something similar with their turboprop experimental design(s) years ago.
 
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