Don't know the answer to all your question, Bob.
But gasoline and ethanol weight about the same per gallon or around 6 lbs
(perhaps a bit more).
The combustible energy content of 1 lb of gasoline is around 20,000 BTU, the
energy of ethanol is around 12,800 BTU. So assuming the combust similarly
for the same fuel burn rate, you would get approx 12,800/20,000 = 64% of the
power compared to using gasoline. I'm not certain whether the amount of
oxygen required to combust 1 lb of ethanol is the same as gasoline, but I
would assume about the same.
So your power (and range) would be adversely affected - however, if 64% of
the power is sufficient to safely fly and you are not concerned about range
and if the ethanol is the right price - there might be a place for it.
I have no idea what unburnt ethanol being dumped into the oil sump would
have, but since they use nitromethane in racing, I would assume no drastic
effects.
There have been reports of adverse effects of auto gas with ethanol on
certain polymers used in aircraft seals and "O" rings, so I would use those
types that are approved for auto use.
Lynn can probably provide more insight to the use of such "alternative"
fuels.
Ed
Well, the power can be the same, but you need to inject about 30% more fuel to do it. This was the fuel of choice for Indy cars with 30 pounds of boost. There is great fuel cooling of the intake charge, so it gives higher octane rating and a colder charge. Then you can use smaller radiators which Indy car people like.
Also used in Saturday night dirt cars, for the cooling effect even with a clogged radiator. Ashland oil used to supply most of it.
The E85 or 85% alcohol motor fuel sucks. I tried a tank of that stuff on a trip to Texas and back, and the torque converter would not lock up. So the mileage under load is dreadful. The problems with interaction with fuels systems has been much reduced, but for older airplanes with tanks molded into the structure, and done with some epoxies, the ethanol may over time dissolve the epoxy . The tanks underground at the gas station are fiberglass reinforced vinyl esters.
The Dodge fuel system may not have been able to adjust to the poorer fuel, and a more modern system may have done better.
Ethanol or grain alcohol (the drinking stuff) is what is now in motor fuels. Methanol, or wood alcohol can be used as well but is harder to make, is poisonous and tastes awful. It is added to ethanol so people wont drink it. 5 billion gallons of fuel ethanol is made each year. About 2 gallons per bushel of corn.
Lynn E. Hanover
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