An airborne vehicle having a wing-body which defines a wing-body axis and appears substantially annular when viewed along the wing-body axis, the interior of the annulus defining a duct which is open at both ends. A propulsion system is provided comprising one or more pairs of propulsion devices, each pair comprising a first propulsion device mounted to the wing-body and positioned on a first side of a plane including the wing-body axis, and a second propulsion device mounted to the wing-body and positioned on a second side of the plane including the wing-body axis. A direction of thrust of the first propulsion device can be adjusted independently of the direction of thrust of the second propulsion device and/or a magnitude of thrust of the first propulsion device can be adjusted independently of the magnitude of thrust of the second propulsion device. In certain embodiments the wing-body appears swept forward when viewed from a first viewing angle, and swept backward when viewed from a second viewing position at right angles to the first viewing angle.