[Problem] To provide a highly safe drone. [Solution] A steering device 401 and a drone 100 that are connected to each other via a network and operate in a coordinated manner. The drone comprises: a flight control unit 23; a flight start command reception unit 51 that receives flight start commands from a user 402; a drone determination unit 53 that determines the configuration of the drone; and an external environment determination unit 54 that determines the external environment of the drone. This drone system has a plurality of mutually different states including at least a takeoff diagnosis state (S5) and moves to a different state when a condition is satisfied. The takeoff diagnosis state includes at least either: a drone determination state (S51) in which the drone determination unit determines the configuration of the drone; and an external environment determination state (S53) in which the external environment determination unit determines the external environment. If a flight start command has been received, the drone system transitions to the takeoff diagnosis state and then causes the drone to take off.