To continuously increase capacity of a conventional rocket drive using a shell flow drive for bringing auxiliary propellant in the area of a drive jacket, and provide a device for executing the method for the same.

The auxiliary propellant is supplied to the area of the drive unit jacket through an element for cooling the drive unit, and fuel and Oxydator are also fed at that time. Furthermore, the auxiliary propellant is simultaneously used as a cooling medium for cooling a delay air. In this device comprising a rocket having the shell flow drive and equipped with the element for injecting the auxiliary propellant to the area of the drive unit jacket and a cooling system, the cooling system is formed as an open system having at least one cooling passage (8, 12) and having an exit opening for the propellant within the area of the drive jacket.