The purpose of this SAE Aerospace Recommended Practice is to standardize locations of aircraft ground service connections to accommodate the trend toward fixed systems, which use the passenger boarding bridge and/or underground "pop-up" or pit systems as a source of utilities. It must be recognized that, in standardizing the locations of the aircraft service connections, they must continue to be served efficiently in those instances where mobile ground support equipment is used. There is an ever increasing number of fixed installations for aircraft servicing. The objectives to be met by standardizing the locations of the aircraft service connections are the following: Reduce ramp congestion and equipment interference around the aircraft, and minimize the chance of aircraft damage from ground support equipment. Allow for optimization of ground services, both fixed and mobile, specifically 400 Hz electric power, preconditioned air for cabin conditioning, pneumatic power for jet engine start, potable water, lavatory service (draining, flushing), aircraft refueling, and interphone (headset) connections. Standardize the locations of the service points around the aircraft to allow airport planners and facility engineers to design their fixed servicing systems to serve all aircraft easily and efficiently, as well as to provide additional standards and parameters for mobile equipment that connects to the aircraft.