Any person subject to this Act, who while he is in an aircraft belonging to or in the service of the Coast Guard, disobeys any lawful command given by the captain of the aircraft whether such captain is subject to this Act or not, in relation to all matters relating to flying or handling of the aircraft or affecting the safety thereof, shall, on conviction by a Coast Guard Court, be liable to suffer imprisonment for a term which may extend to seven years or such less punishment as is in this Act mentioned.