An unmanned aircraft including at least two supporting legs, the unmanned aircraft comprising: at least two generators that generate forces to fly the unmanned aircraft, the at least two generators each including a rotor blade that generates an airflow; a sensor that detects a tilt of the unmanned aircraft; and a processor that controls the at least two generators to control flight of the unmanned aircraft, characterized in that the processor: obtains, in a state in which the unmanned aircraft is placed on a ground that is horizontal, an output force adjustment trigger for the at least two generators; upon obtaining the output force adjustment trigger, causes each of the at least two generators to individually operate in a state in which at least one of the at least two supporting legs is in contact with the ground and at least until the tilt of the unmanned aircraft detected by the sensor satisfies a predetermined condition; determines a reference value related to an output force of each of the at least two generators from (i) a value related to the output force of each of the at least two generators at a timing at which the tilt of the unmanned aircraft satisfies the predetermined condition and (ii) a positional relationship between the at least two generators; and controls the flight of the unmanned aircraft, using the reference values determined. at least two generators that generate forces to fly the unmanned aircraft, the at least two generators each including a rotor blade that generates an airflow; a sensor that detects a tilt of the unmanned aircraft; and a processor that controls the at least two generators to control flight of the unmanned aircraft, characterized in that the processor: obtains, in a state in which the unmanned aircraft is placed on a ground that is horizontal, an output force adjustment trigger for the at least two generators; upon obtaining the output force adjustment trigger, causes each of the at least two generators to individually operate in a state in which at least one of the at least two supporting legs is in contact with the ground and at least until the tilt of the unmanned aircraft detected by the sensor satisfies a predetermined condition; determines a reference value related to an output force of each of the at least two generators from (i) a value related to the output force of each of the at least two generators at a timing at which the tilt of the unmanned aircraft satisfies the predetermined condition and (ii) a positional relationship between the at least two generators; and controls the flight of the unmanned aircraft, using the reference values determined. obtains, in a state in which the unmanned aircraft is placed on a ground that is horizontal, an output force adjustment trigger for the at least two generators; upon obtaining the output force adjustment trigger, causes each of the at least two generators to individually operate in a state in which at least one of the at least two supporting legs is in contact with the ground and at least until the tilt of the unmanned aircraft detected by the sensor satisfies a predetermined condition; determines a reference value related to an output force of each of the at least two generators from (i) a value related to the output force of each of the at least two generators at a timing at which the tilt of the unmanned aircraft satisfies the predetermined condition and (ii) a positional relationship between the at least two generators; and controls the flight of the unmanned aircraft, using the reference values determined.