An annular array of turning vanes 200 is provided in a duct 100 of a gas turbine engine 10. The annular array of turning vanes 200 comprises aerodynamic vanes 220 and strut-vanes 240. The strut-vanes 240 have greater chord length and extend further axially downstream than the aerodynamic vanes 220. The leading edge of the strut-vanes 240 is upstream of the trailing edge of the aerodynamic vanes 220. The strut-vanes provide flow turning. The space to chord ratio of the aerodynamic vanes that are closest to the suction surface of a strut-vane is higher than the space to chord ratio of aerodynamic vanes that are closest to a pressure surface of the strut-vane. The arrangement allows the duct 100 to be axially short.