Apparatus for generating gas turbine engine thrust

A pulse detonation system (12) for a gas turbine engine (10) includes a core engine (30). The pulse detonation system is downstream from the core engine and is configured to create a temperature rise and a pressure rise within the gas turbine engine and to increase engine thrust. The pulse detonation system comprises a multi-staged pulse detonation augmentor (60) that comprises a predetonator (48) operable with at least a first operating stage wherein a less-than-stoichiometric fuel-air mixture is provided to the predetonator.