Abstract: An annular combustion chamber which has structural elements for delivery of primary air to sustain and stabilize burning and elements for admission of secondary air into the dilution zone. The primary air delivery elements intended for stabilization of burning are made so that at least two curved slotted passages are formed for tangential admission of the air into the combustion zone. The passage wall plates are concentric, being arranged so that the outer wall plate of each preceding passage is naturally the inner wall plate of the subsequent one displaced relative to the former in the downstream direction. The slotted passages have a substantially constant flow-passage along the entire annular combustion chamber periphery (length).