Ethanol Blended Fuels

I was talking with an old timer the other day about aircraft engines and we started into the topic of fuel availability. With the many automotive based engines being installed in aircraft he felt that there was a risk in having ethanol blended into the gasoline.
Now, I know that this is a problem with the current aircraft engines in that the water will plug the filter screen in the fuel pump but is it a problem when we are using automotive based technology? Aren't these engines and their fuel systems designed to handle blended fuel?

Dave Hertner

Dave Hertner said:

I was talking with an old timer the other day about aircraft engines and we started into the topic of fuel availability. With the many automotive based engines being installed in aircraft he felt that there was a risk in having ethanol blended into the gasoline.
Now, I know that this is a problem with the current aircraft engines in that the water will plug the filter screen in the fuel pump but is it a problem when we are using automotive based technology? Aren't these engines and their fuel systems designed to handle blended fuel?

Dave Hertner

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Dave, While many of the automotive setups will tolerate, emphasis on tolerate, alcohol, most owners manuals will tell you to avoid blended alcohol fuels specifically. There was a discussion of tolerance of composites and sealants of NEW aircraft to alcohol mixes on another forum. Many types of composite and several sealants are badly effected by alcohol in a mix exactly the ratio in Gasahol, around 10%. The problem with many materials is that they absorb alcohol and that enables the other solvents to break down the matrix. That is if the alcohol doesn't do it itself!
Simply said, AVOID ALCOHOL OXYGENATED FUELS LIKE THE PLAGUE.
Bill Jepson
rotary10-RV