Gas generator and jet engine being equipped with the same for starting

The generator has an annular case (11) forming a chamber for a pyrotechnic load (12) and composed of unitary load segments (120). The segments have an external dimension lower than the chamber so that passages constituting circulation paths for gas products during combustion of the load are arranged between segments and the case. Vents or exhaust ports (111) are arranged on the case for ejecting the products during combustion. An independent claim is also included for a jet engine comprising a gas generator.