64. Any person subject to this Act who, whatever his rank, commits any of the following offences, that is to say:-(a) while he is in an aircraft disobeys any lawful command given by the captain of the aircraft, whether such captain is subject to this Act or not as respects all matters relating to the flying or handling of the aircraft, or affecting the safety thereof; or(b) being the captain of a glider aircraft towed by another aircraft disobeys any lawful command given by the captain of the towing aircraft, whether the latter is subject to this Act or not, as respect all matters aforesaid;shall, on conviction by court-martial, be liable to suffer long imprisonment.