For the purposes of this part, surplus airport property is any surplus real property including improvements and personal property included as a part of the operating unit that the Administrator of FAA deems is -
(a) Essential, suitable, or desirable for the development, improvement, operation, or maintenance of a public airport, as defined in the Federal Airport Act, as amended (49 U.S.C. 1101); or
(b) Reasonably necessary to fulfill the immediate and foreseeable future requirements of the grantee for the development, improvement, operation, or maintenance of a public airport, including property needed to develop sources of revenue from non-aviation businesses at a public airport. Approval for non-aviation revenue-producing areas may only be given for such areas as are anticipated to generate net proceeds that do not exceed expected deficits for operation of the aviation area applied for at the airport.