As used in this chapter, the following terms mean:
(1) "Aircraft", any contrivance now known, or hereafter invented, used or designed for navigation of, or flight in, the air;
(2) "Airline company", any person, firm, partnership, corporation, trustee, receiver or assignee, and all other persons, whether or not in a representative capacity, undertaking to engage in the carriage of persons or cargo for hire by commercial aircraft pursuant to certificates of convenience and necessity issued by the federal Civil Aeronautics Board, or successor thereof, or any noncertificated air carrier authorized to engage in irregular and infrequent air transportation by the federal Civil Aeronautics Board, or successor thereof;
(3) "Aviation fuel", any fuel specifically compounded for use in reciprocating aircraft engines;
(4) "Commercial aircraft", aircraft fully equipped for flight and of more than three thousand pounds maximum certified gross take-off weight.