Abstract: The present invention relates to a device for imparting a movement of rotation to a craft with nozzle propulsion system during launching thereof by means of a launching member, said device comprising: a wheel with vanes or fins formed by a section of tube located in the rear extension of the nozzle, the tube section having an outer surface at least partly in permanent contact with the launching member during its path inside said latter, and bearing, on the inside, vanes or fins constituting surfaces deflecting the jet produced by the nozzle, the wheel being divided into distinct annular sectors juxtaposed to form said tube section, each sector extending over an angle at the most equal to 180.degree.

Abstract: Tail unit for a missile comprising at least one system of two pairs of curved blades, whereof one of the longitudinal edges is fixed to the periphery of a cylindrical body, whereby the blades of the same pair are symmetrical relative to the axis of said body are fixed to the latter in two diametrically opposite zones and have their concavity turned in the same direction about the axis of said body, wherein the orientation of the concavity of the blades of the same pair of blades around the axis of the cylindrical body is opposite to that of the blades of the other pair.The said tail unit makes it possible to improve the stability of the trajectory of the missile on which it is mounted, when a rotary movement is given to the missile.