Abstract: A combustor for a gas turbine is provided, the combustor including a reverse flow type combustion chamber defined by an inner cylindrical wall and an outer wall concentric with the inner wall and connected at one end by an annular dome. The outer wall has three successive sections with the first section being cylindrical and of a predetermined diameter, the second outer wall section being of frusto-conical shape, and the third wall section being of cylindrical shape but of reduced diameter compared to the first section. Injectors are provided in the angled wall of the second outer wall section, and openings are provided annular with the injectors to allow compressor delivered air to enter directly into the combustion chamber surrounding the injector, the injector being directed towards the primary zone.