Abstract: Disclosed is a tail-sitter aircraft. The aircraft comprises a fuselage for carrying a payload, a first lift body and a second lift body offset from the first lift body normal to a plane of the first lift body, and one or more first rotors and one or more second rotors. The first rotor(s) are mounted to the first lift body and the second rotor(s) are mounted to the second lift body. The aircraft also includes a controller that, in some cases, is configured to change a speed of one or more of said propulsion units relative to a speed of one or more other ones of said propulsion units, to adjust an orientation of the aircraft around one or more primary axes. The primary axes are the pitch, roll and yaw axes. In some cases, a position of the payload relative to the lift bodies is adjustable.