An airblast fuel injector for a fuel spray nozzle of a gas turbine engine, the injector having, in order from radially inner to outer, a coaxial arrangement of an inner air swirler passage, an annular fuel passage, an annular outer air swirler passage, and an annular shroud air swirler passage, fuel exiting the fuel passage being atomised into a spray by surrounding swirling air exiting the inner, outer and shroud air passages, wherein: the injector has an annular shroud having an inner surface profile which defines a radially outer side of the shroud air passage, relative to the overall axial direction of flow through the injector the shroud inner surface profile having a convergent section corresponding to a convergent portion of the shroud air passage, the convergent section of the shroud inner surface profile being followed by a divergent section of the shroud inner surface profile, the transition from the convergent section to the divergent section of the shroud inner surface profile forming a first inwardly directed annular nose; and the injector further has an annular wall having an outer surface profile which defines a radially inner side of the shroud air passage, and having an inner surface profile which defines a radially outer side of the outer passage, relative to the overall axial direction of flow through the injector the wall outer surface profile having a convergent section corresponding to the convergent portion of the shroud air passage, the convergent section of the wall outer surface profile being followed by an outwardly turning section which faces across the shroud air passage to the first nose, relative to the overall axial direction of flow through the injector the wall inner surface profile has a convergent section corresponding to a convergent portion of the outer passage, the convergent section of the wall inner surface profile being followed by a divergent section of the wall inner surface profile, the transition from the convergent section to the divergent section of the wall inner surface profile forming a second inwardly directed annular nose, wherein on longitudinal cross-sections through the injector the outwardly turning section maintains a constant width for the shroud air passage as it turns around the first nose, the divergent section of the wall inner surface profile and the divergent section of the shroud inner surface profile have the same conic angle (α). the injector has an annular shroud having an inner surface profile which defines a radially outer side of the shroud air passage, relative to the overall axial direction of flow through the injector the shroud inner surface profile having a convergent section corresponding to a convergent portion of the shroud air passage, the convergent section of the shroud inner surface profile being followed by a divergent section of the shroud inner surface profile, the transition from the convergent section to the divergent section of the shroud inner surface profile forming a first inwardly directed annular nose; and the injector further has an annular wall having an outer surface profile which defines a radially inner side of the shroud air passage, and having an inner surface profile which defines a radially outer side of the outer passage, relative to the overall axial direction of flow through the injector the wall outer surface profile having a convergent section corresponding to the convergent portion of the shroud air passage, the convergent section of the wall outer surface profile being followed by an outwardly turning section which faces across the shroud air passage to the first nose, relative to the overall axial direction of flow through the injector the wall inner surface profile has a convergent section corresponding to a convergent portion of the outer passage, the convergent section of the wall inner surface profile being followed by a divergent section of the wall inner surface profile, the transition from the convergent section to the divergent section of the wall inner surface profile forming a second inwardly directed annular nose, wherein on longitudinal cross-sections through the injector the outwardly turning section maintains a constant width for the shroud air passage as it turns around the first nose, the divergent section of the wall inner surface profile and the divergent section of the shroud inner surface profile have the same conic angle (α).