> Paul,
     >
     > It is not correct that range has to suffer by burning
    ethanol. In
     > fact range can increase if you fly above 10,000 ft density
    altitude.
     >
     > The reason is that ethanol has an oxygen content of about 25
     > percent. The effect is like supercharging, or nitrous oxide, or
     > dragsters that use nitromethane which has huge amounts of oxygen.
     > Gordon

    Sorry, this is not correct -- the oxygen in ethanol is
    representative of
    the fact that is has been partially oxidized, in other words,
    partially
    burned. So some of the energy content has been expended over being a
    hydrocarbon. Nitromethane is a different story. The oxygen can
    come free
    of the nitro-groups and combine with any available hydrocarbons.

    You carry less energy per pound with ethanol, how you use it
    determines
    your specific fuel consumption, milage, etc.

    The evaporative cooling effects and octane effects are real, but the
    oxygen content has already been used up ( i.e. not available).

    Bill Schertz


    Bill,

    Thanks for that insight.

    What exactly do you mean by, "partially oxidized?" The way I
    understand it pure ethanol has an oxygen content of 35 percent, so
    all of that oxygen should be available for oxidization, no? (AGE 85
    is only 85 percent ethanol -- the rest is pentane isomerate -- so
    its oxygen content is about 30 percent.)

    The oxygen is the reason the stoichiometric air-fuel ratio of
    ethanol is lower than gosoline -- because when you add the same
    volume of air, there is more total oxygen due to the oxygen embedded
    in the fuel, so you need more fuel to completely oxidize the extra
    oxygen. See the attached table, "Ethanol Gasoline Properties."

    The heat energy of ethanol per pound or per gallon is lower than
    gasoline, as you pointed out. However, the oxygen in the ethanol
    results in better thermodynamic efficiency, so power actually goes
    up. You can see in the attached chart that an O-470 engine running
    on AGE85 has 15 percent more peak power.

    The graphic on flight test data shows that at 10,000 feet a Mooney
    with an IO-360 running AGE85 has a fuel burn at lean mixture that is
    less than the same plane on avgas at 8,000 feet. One of the
    advantages of ethanol is that very lean mixtures can be safely run.



    Regards,

    Gordon.



    Gordon,
    What adverse effects are there on housings when you use Ethanol ? I had
    developed and manfactred seals which resist methanol and future long
    life oil detergints. These could be used on a rotary engines too,
    however I had the impletion that Ethanol, Methanol etc corrod the
    housing.

    regards
    Roderick


    Roderick,

    As far as I can find from the literature, AGE 85 is compatible with
    existing fuel system materials.

    Here are some snippets from I think Baylor University which has lots
    of info on AGE 85.


    Regards,

    Gordon.




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