Abstract: A gas turbine engine fuel burner comprises the combination of an atomising fuel nozzle and a vaporizing duct in which the atomised fuel is arranged to impinge on the wall of the vaporizing duct and mix with a portion of the compressor delivery air from the engine compressor. The resultant fuel and air mixture flows into the combustion chamber through a plurality of equi-spaced elongated slots formed in the cylindrical wall of the vaporizing duct, each of the elongated slots having its major axis or longest side extending parallel to the longitudinal axis of the duct.