This Aerospace Information Report (AIR) outlines the conditions which diesel engines should meet when installed and used as prime movers for aircraft ground support equipment at commercial airports. All aircraft ground support equipment with a heavy duty diesel engine as defined on page 24293 of the November 15, 1972 Federal Register and used as a prime mover for the vehicle or equipment should meet all requirements as outlined herein. Typical equipment includes fuel trucks, commissary trucks, baggage tractors, ground power units, air start units, etc.