In this chapter, “aircraft” includes balloon, airplane, hydroplane, and every other vehicle used for navigation through the air. A hydroplane, while at rest on water and while being operated on or immediately above water, shall be governed by the rules regarding water navigation; while being operated through the air otherwise than immediately above water, it shall be treated as an aircraft.

“Aeronaut” includes aviator, pilot, balloonist, and every other person having any part in the operation of aircraft while in flight.

“Commercial use” includes the carriage in air commerce of persons or property for compensation or hire, and the lease or rental of any aircraft.

“Passenger” includes any person riding in an aircraft but having no part in its operation.