April 2014- In 1990 amendments to the Clean Air Act were enacted. In 1995 the industry and the FAA started seriously searching for an unleaded 100 octane avgas. In the intervening time 245 fuels were tested by the FAA at its William J. Hughes Technical Center; the testing was overseen by the Coordinating Research Council (CRC). That testing yielded 45 blends that held promise.