Abstract: Propellant charge, the combustion of which takes place according to at least two thrust modes, and which makes it possible to obtain at least one acceleration phase and one cruising phase of the self-propelled device equipped with this charge.The propellant charge is of the so-called "trumpet block" type with radial combustion from a central channel which has a star-shaped cross-section over a length equal to at least one third of the total length of this charge. In order to obtain at least one dual combustion mode using only a single charge of propellant, that part of the channel which is of star-shaped cross-section possesses at least one zone in which the star of the channel has at least four arms which determine at least two tooth-like sectors of propellant with a large sector angle (A) and at least two tooth-like sectors of propellant with a small sector angle (a), distributed symmetrically relative to the axis of the charge.

Abstract: Pyrotechnic charge, with a short combustion time, comprising inclined plates of propellant and deflectors, and a propulsion system using a charge of this type.The pyrotechnic charge is intended especially for use in a propulsion system for acceleration, and it comprises a set of plates of solid propellant, which plates are arranged approximately parallel to one another and provide at least one longitudinal channel for discharging the combustion gases in the direction of the nozzle of the propulsion system. In order to achieve a very high flow rate of gas without causing breakage of the plates of propellant, the plates of propellant (6) are inclined towards the longitudinal channel, and the charge comprises deflectors (5) which are arranged approximately parallel to the plates of propellant and which possess, in a longitudinal cross-section of the charge, a length which is equal to or greater than the length of the plates of propellant.