1,075,958. Gas turbine engines; gas turbine combustion equipment. ROLLS ROYCE Ltd. April 29, 1966, No. 19051/66. Headings F1G and F1L. A gas turbine engine comprises an annular flow duct 11 within which are mounted in flow series a low pressure compressor, a high pressure compressor, combustion equipment, a high pressure turbine and a low pressure turbine, there being fuel injectors 27 for injecting fuel into the combustion equipment, also a plurality of angularly spaced apart, radially-extending hollow struts 31 which are disposed downstream of the high pressure compressor and upstream of the fuel injectors, the hollow struts extending into the annular flow duct 11 and having inner ends 33 which are disposed adjacent to the inner wall 12 of the annular flow duct so as to receive air under pressure flowing along the inner wall, there being conduit means for passing to a point externally of the engine air under pressure which flows radially outwardly through the hollow struts. In the embodiment shown, the annular flow duct 11 is defined between inner and outer walls 12, 13 and the combustion equipment comprises an annular flame tube 18 which is spaced from the walls 12., 13 so as to define air flow passages 25, 23. Fuel is supplied to the combustion equipment through a conduit 26 and fuel injectors 27. A series of hollow radial struts 31 extend radially across the flame tube 18 upstream of the fuel injectors 27, the struts extending to the engine outer casing 14 where they are supported on radial studs 32, the struts which are secured to the flame tube thus serving to locate the upstream end of the flame tube. The radially outer ends of the struts communicate with an annular manifold 34 so that air tapped from the inner annular passage 25 may flow radially outwardly through the struts 31 to the annular manifold 34, the air then passing through duct 35 to a point of use such as for use in aircraft cabin pressurization. Further air under pressure is tapped from the flow adjacent the inner wall 12 through openings 36 into the annular chamber 37, this air then flowing radially outwardly through the hollow compressor outlet guide vanes 17 to the manifold 34 and thence through duct 35.