You don't say what kind of aircraft or more importantly what kind of engine. Assuming that the aircraft engine will run, or has been modified to run on ethanol, the biggest problem you face is in flight planning. Ethanol has a lower specific energy (Joules / Kg) than petroleum fuels. This means fuel consumption will be higher. You will need to carry more and carry more again to carry the extra weight. Maximum range will be about half to three quarters the equivalent petroleum fueled aircraft. Other problems are that ethanol is more corrosive to aircraft systems than petroleum, freezes at a higher temperature and can cause vapour lock at lower temperatures. Increased volatile organic compounds help destroy the ozone layer and avoid inhaling the exhaust at idle power, higher organic acids and aldehydes.