PURPOSE: To eliminate external wirings in a rocket, by connecting an electric igniter of an igniter at the tail side to a power source throug wires penetrating a propellant.

CONSTITUTION: A liner 5 is pasted to the inside of a motor case 1, to which front end a front end plate 2 is engaged and to which rear end a tail end plate 4 with nozzles such as four nozzles respectively, and a propellant 6 is filled in the inside, but wires 8, 8' are buried into the propellant 6 in parallel with the motor case 1, and the end portions 8A, 8A', 8B, 8B' are projected from the propellant 6. The one ends of the lead wires 10, 10' of an electric igniter of an igniter 9 are connected to said end portions 8B, 8B' through lead wires 11, 11', and the end portions 8A, 8A' are coupled with a connector 13 through lead wires 12, 12' and 14, 14' and connected to a power source on a machine not shown in the figure through a lead wire 15, 16 is a bulking agent.