AvGas

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Interesting article in Air & Space Magazine this month on the plight of general aviation as it relates to the EPA's determination to outlaw the last leaded fuel supplies. The planet will be saved, of course, and the bureaucrats jobs secure.
 
GA is dying...no one wants to learn to fly...it's expensive...so we're caught in a downward spiral of airports closing, more expensive insurance, more expensive fuel, more expensive airplanes...creating more barriers to flying, which raises the cost for those who do fly...
 
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Originally Posted By: satinsilver
LAME!
You want to elaborate on that or is that the extent of you vocabulary for the week?
 
Lead gas burn mams better at aktitude. Thats what two oilots i know have said.both of them i yrust and fly eith. Spent two hrs in the centobra and three in the bonanza two weeks ago. Not a bad two days on a ppo holiday.wayne is a 35 plus year ga veteran. Plus 30 years heavy transport and tanker pilot for national guard.

Kc
 
Originally Posted By: expat
We have gone Lead Free in automotive gas for decades now, why do we need it in AvGas?


Lead is absolutely the BEST anti knock compound available for piston engines at high altitudes. There are other compounds that work, but not as well and not in turbocharged aircraft engines.

For years more compounds have been in development, and show much promise. There are numerous non turbocharged pistons that will run on automotive fuels at high altitude, and those fuels are improving rapidly for that use, as is engine technology.
 
Originally Posted By: JR
Lead gas burn mams better at aktitude. Thats what two oilots i know have said.both of them i yrust and fly eith. Spent two hrs in the centobra and three in the bonanza two weeks ago. Not a bad two days on a ppo holiday.wayne is a 35 plus year ga veteran. Plus 30 years heavy transport and tanker pilot for national guard.

Kc


How drunk are you bro?
 
Originally Posted By: abycat
Originally Posted By: JR
Lead gas burn mams better at aktitude. Thats what two oilots i know have said.both of them i yrust and fly eith. Spent two hrs in the centobra and three in the bonanza two weeks ago. Not a bad two days on a ppo holiday.wayne is a 35 plus year ga veteran. Plus 30 years heavy transport and tanker pilot for national guard.

Kc


How drunk are you bro?


It's the lead!
 
In those air cooled engines, valves get hot... and the lead helps protect valve seats in addition to the anti-knock (again, air-cooled, so prone to detonation).
 
Originally Posted By: expat
We have gone Lead Free in automotive gas for decades now, why do we need it in AvGas?
Try reading.... the Air & Space article.
 
One of the fuels which MAY be able to take the place of the leaded stuff is a SYNTHETIC fuel. Of course for private pilots the cost will be, well, "up there".
 
Originally Posted By: HerrStig
Originally Posted By: satinsilver
LAME!
You want to elaborate on that or is that the extent of you vocabulary for the week?


Sure, I think it's "LAME" that leaded av fuel is soon going to dissappear.
 
Originally Posted By: HerrStig
Originally Posted By: expat
We have gone Lead Free in automotive gas for decades now, why do we need it in AvGas?
Try reading.... the Air & Space article.


I don't happen to have a copy handy at the moment
33.gif
 
Originally Posted By: Astro14
GA is dying...no one wants to learn to fly...it's expensive...so we're caught in a downward spiral of airports closing, more expensive insurance, more expensive fuel, more expensive airplanes...creating more barriers to flying, which raises the cost for those who do fly...


A lady at work and her husband own a Arrow...old one.

At the time that they bought it, it wasvabout the price of a 5 series BMW...maintenance is huge cost for a family (better than falling out of the sky)
 
Originally Posted By: expat
We have gone Lead Free in automotive gas for decades now, why do we need it in AvGas?


Note: My Cessna Cardinal 177RG has a 200HP angle valve, high compression (ha ha) Lycoming engine. And, I can get it to detonate on 100LL Avgas. Fortunately, I have good instruments and when CHT climbs quickly, I know I have detonation. I've been able to hear it too on occasion, but most of the time, it's just too noisy to discern the "pinging". Full-Rich solves the problem.

100 Octane "non oxygenated" unleaded is a difficult task. And, 100 Octane unleaded that meets 100% or the requirements of aviation has proven to be nearly impossible. (cold start, high altitude start, detonation margin lean vs. rich etc)

Swift fuels has developed a 102 Octane unleaded that meets most of the requirements. It's a binary fuel composed of (I believe) Trimethylbenzene and Isopentane. I've never used it, but I do think it has promise. Interestingly, it's more dense (weighs more) and has higher energy content per gallon than 100LL. That does translate into more MPG in properly tuned and leaned engines. (not more HP though)

I have to wonder about the cold start characteristics of Swift's creation. Not that it matters much to me here in South Florida. I've tried for a few years to procure some for testing in our high compression stunt plane (experimental) without luck.

Swift Fuels Unleaded Aviation gasoline

fuel_bottles-190x108.jpg
 
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By the way, I truly believe the perfect storm has hit General Aviation. Making it a rich man's hobby and otherwise impractical for average individuals.

I love my airplane, but $7.35 Avgas is stupid expensive at my home base (F45, Jupiter, Florida)

Government is working on a solution by fiddling with certification regulations, hogwash! I have a suggestion. Cut fuel prices by 2/3. Or enjoy the nearly complete loss of General Aviation in the next 20 years.
 
One VERY misleading thing in that article...

They say 70% of the GA fleet can use lower octane. (true)
They say 30% of the GA fleet needs 100 octane. (also true)

What they don't clearly state is that those 70% do very little flying (piper cubs and such) and burn very little fuel by percentage. Notice that the aircraft capable of using low octane fuels are not practical aircraft. They are slow, low flying toys.

Another inaccuracy: They state 100LL has 2grams TEL per gallon. (not true) , 100LL can contain UP TO 2g/gal TEL. But today's fuel generally contains 0.5g/gal TEL.

The major consumer of Avgas, by number of gallons used AND by number of miles traveled, ARE the aircraft that need high octane.


Let's also review how Lycoming, Continental and other clones get aircraft engines to reliably operate on lower octane fuels. They reduce compression ratio significantly, they remove turbochargers and they increase displacement in an attempt at keeping HP acceptable. All while adding weight (larger engine) and increasing fuel consumption (less efficient engine) which translates directly in to a slight reduction in payload and range.
 
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It would be a shame if you had to park your fully restored Cardinal due to fuel prices.

I remember you posting pictures of the restoration and rebuild.
 
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