Specialized Aviation Service Operations (SASO) are defined by the Federal Aviation Administration as single-service providers or special fixed-base operators performing less than full services. These types of companies differ from a full-service FBO in that they typically offer only a specialized aeronautical service such as aircraft sales, flight training, aircraft maintenance, or avionics services for example.
Examples of SASOs are companies that provide aircraft technical services; avionics repair and installation; reciprocating engine repair and overhaul; turbine engine hot section and overhaul; aircraft component and accessory overhaul; standalone flight schools; specialized vendors of pilots supplies; aircraft detailing and cleaning services; and aircraft in-flight catering services. An ARGI survey completed in April 2009 put the number of U.S. businesses meeting the minimum criteria for a SASO at 667. Since no previous census of the number of SASOs has been conducted, 2009 represents the baseline for the annual ARGI SASO census.