During the period 1970-80, there were reported in USAF 89 incidents of smoke/fumes in the cockpit during flight. The origin of the fumes in most cases was organic petroleum derivatives, which caused a multitude of symptoms including CNS dysfunction and mucous membrane irritation. Flight surgeons should be well-read in aerospace toxicology because of the threat to flying safety posed by the many fluids and substances necessary for the operation of today's modern aircraft.