in-flight security officer
as defined in Regulation (EC) No 300/2008 of the European Parliament and of the Council of…, Article 3, point (31) (Definitions)
31.
‘in-flight security officer’ means a person who is employed by a state to travel on an aircraft of an air carrier licensed by it with the purpose of protecting that aircraft and its occupants against acts of unlawful interference that jeopardise the security of the flight.