18 U.S.C. § 31
Section 31 · Definitions
Current version, with additions and removals from the July 5, 1994 version.
When used in this chapter the term—
“Aircraft engine”, “air navigation facility”, “appliance”, “civil aircraft”, “foreign air commerce”, “interstate air commerce”, “landing area”, “overseas air commerce”, “propeller”, “spare part” and “special aircraft jurisdiction of the United States” shall have the meaning ascribed to those terms in sections 40102(a) and 46501 of title 49.
“Motor vehicle” means every description of carriage or other contrivance propelled or drawn by mechanical power and used for commercial purposes on the highways in the transportation of passengers, passengers and property, or property or cargo;
(a) Definitions.—In this chapter, the following definitions apply:
(1) Aircraft.—The term “aircraft” means a civil, military, or public contrivance invented, used, or designed to navigate, fly, or travel in the air.
(2) Aviation quality.—The term “aviation quality”, with respect to a part of an aircraft or space vehicle, means the quality of having been manufactured, constructed, produced, maintained, repaired, overhauled, rebuilt, reconditioned, or restored in conformity with applicable standards specified by law (including applicable regulations).
“Used for commercial purposes” means the carriage of persons or property for any fare, fee, rate, charge or other consideration, or directly or indirectly in connection with any business, or other undertaking intended for profit;
(4) In flight.—The term “in flight” means—
(B) in the case of a forced landing, until competent authorities take over the responsibility for the aircraft and the persons and property on board.
(5) In service.—The term “in service” means—
(B) in any event includes the entire period during which the aircraft is in flight.
(6) Motor vehicle.—The term “motor vehicle” means every description of carriage or other contrivance propelled or drawn by mechanical power and used for commercial purposes on the highways in the transportation of passengers, passengers and property, or property or cargo.
(7) Part.—The term “part” means a frame, assembly, component, appliance, engine, propeller, material, part, spare part, piece, section, or related integral or auxiliary equipment.
(8) Space vehicle.—The term “space vehicle” means a man-made device, either manned or unmanned, designed for operation beyond the Earth's atmosphere.
(9) State.—The term “State” means a State of the United States, the District of Columbia, and any commonwealth, territory, or possession of the United States.
(10) Used for commercial purposes.—The term “used for commercial purposes” means the carriage of persons or property for any fare, fee, rate, charge or other consideration, or directly or indirectly in connection with any business, or other undertaking intended for profit.
(b) Terms Defined in Other Law.—In this chapter, the terms “aircraft engine”, “air navigation facility”, “appliance”, “civil aircraft”, “foreign air commerce”, “interstate air commerce”, “landing area”, “overseas air commerce”, “propeller”, “spare part”, and “special aircraft jurisdiction of the United States” have the meanings given those terms in sections 40102(a) and 46501 of title 49.