Gasoline sold for use in aircraft will be exempt from an ethanol blending requirement under a new initiative signed by Gov. Charlie Crist on June 25. Under H.B.7135, auto gasoline must be blended with 10 percent ethanol by 2010. The measure does allow exceptions for fuel sold for use in aircraft but does not guarantee the availability of unblended fuel. While blended fuel is harmless to cars, it can cause problems with aircraft fuel bladders, seals, and engines.