A gas turbine engine defining axial, radial and circumferential directions and comprising: a duct defined by an axially extending radially inner wall and an axially extending radially outer wall, wherein: an annular array of turning vanes is provided in the duct, the array comprising a set of cambered aerodynamic vanes and a set of cambered strut-vanes, each having leading edges (225, 245) and trailing edges (226, 246); a plurality of the aerodynamic vanes are provided in a gap defined by a suction surface of one of the strut-vanes and a pressure surface of another of the strut-vanes; the leading edges of the strut-vanes are axially upstream of the trailing edges of the aerodynamic vanes; the trailing edges of the strut-vanes extend further axially downstream than the trailing edges of the aerodynamic vanes; and the pitch to chord ratio of the aerodynamic vanes in the gap that are closest to the suction surface of the strut-vane is higher than the pitch to chord ratio of aerodynamic vanes in the gap that are closest to the pressure surface of the strut-vane, characterised in that the pitch (p) between the two aerodynamic vanes (2201, 2202) that are closest to the suction surface of the strut-vane that defines the gap is greater than the pitch between the two aerodynamic vanes (2204, 2205) that are closest to the pressure surface of the strut-vane that defines the gap. a duct defined by an axially extending radially inner wall and an axially extending radially outer wall, wherein: an annular array of turning vanes is provided in the duct, the array comprising a set of cambered aerodynamic vanes and a set of cambered strut-vanes, each having leading edges (225, 245) and trailing edges (226, 246); a plurality of the aerodynamic vanes are provided in a gap defined by a suction surface of one of the strut-vanes and a pressure surface of another of the strut-vanes; the leading edges of the strut-vanes are axially upstream of the trailing edges of the aerodynamic vanes; the trailing edges of the strut-vanes extend further axially downstream than the trailing edges of the aerodynamic vanes; and the pitch to chord ratio of the aerodynamic vanes in the gap that are closest to the suction surface of the strut-vane is higher than the pitch to chord ratio of aerodynamic vanes in the gap that are closest to the pressure surface of the strut-vane, an annular array of turning vanes is provided in the duct, the array comprising a set of cambered aerodynamic vanes and a set of cambered strut-vanes, each having leading edges (225, 245) and trailing edges (226, 246); a plurality of the aerodynamic vanes are provided in a gap defined by a suction surface of one of the strut-vanes and a pressure surface of another of the strut-vanes; the leading edges of the strut-vanes are axially upstream of the trailing edges of the aerodynamic vanes; the trailing edges of the strut-vanes extend further axially downstream than the trailing edges of the aerodynamic vanes; and the pitch to chord ratio of the aerodynamic vanes in the gap that are closest to the suction surface of the strut-vane is higher than the pitch to chord ratio of aerodynamic vanes in the gap that are closest to the pressure surface of the strut-vane, characterised in that the pitch (p) between the two aerodynamic vanes (2201, 2202) that are closest to the suction surface of the strut-vane that defines the gap is greater than the pitch between the two aerodynamic vanes (2204, 2205) that are closest to the pressure surface of the strut-vane that defines the gap.