Abstract: A gas turbine fan engine with improved maintainability features is disclosed. Forward and rearward sections of the core of the engine are joined one to the other, and each are independently separable from the pylon on which the engine is mounted without the necessity of removing the other from the airplane.

Abstract: An oil lubricating and cooling system is positioned in the engine cowl and includes a heat exchanger, a compressor for delivering air from air inlets in the surface of the cowl through the heat exchanger and hence to air outlets also in the cowl surface and oil pumps also located within the cowl for circulating oil from the sump in the cowl to the heat exchanger to the reduction gear within the cowl that serve to drive the fan also supported within the cowl and having the blades extending outwardly therefrom. The reduction gear, compressor and pumps are all driven from the engine shaft, the end of which is located in the cowl.

Abstract: A non-rotating actuating system for pitch control of a fan in a bypass turbine engine in which the actuating sleeve, that rotates with a fan and is moved axially to change to the pitch ofthe fan blade, is supported by a part of the fixed structure thereby to minimize loading of the disc supporting structure.

Abstract: A composite support disc for a row of fan blades in a bypass turbine engine in which the ring is made up of plies of high strength fibers so oriented as to carry the loading developed on the ring by the fan and with the fan blades mounted to minimize the loading on the composite disc. The orientation of the fibers are different in selected areas of the disc to provide a high strength disc with a minimum weight.

Abstract: In a gas turbine engine with a bypass duct, a rotating stage of airfoils in the bypass duct is supported through and driven by torque transmitting members extending across the core stream flow path, but which are sufficiently flexible in the radial direction to avoid passing centrifugal loads from the rotating stage across the core stream flow path. The rotating bypass stream stage is also supported through a bearing secured directly to the engine main support structure radially outwardly of the core stream flow path. The majority of aircraft maneuver loads are reacted at this bearing, and a minor portion of the maneuver loads pass across the core stream to a bearing located radially inwardly thereof. The airfoils may be either variable pitch airfols or fixed airfoils. If variable pitch, they may be used to reverse the flow in the bypass duct for thrust reversing.

Abstract: A turbine intermediate case in which the outer case element carries a series of inwardly extending struts that position the bearing support centrally within the outer case element and these struts support the inner case element within and in spaced relation to the outer case element. The inner case element carries seals at opposite ends, a diaphragm and a support ring for the row of turbine vanes downstream of the case. The struts provide a vent for the air cavity formed by the diaphragm and carry a baffle to control heat transfer between strut and vent air.

Abstract: A turbine intermediate case in which a turbine bearing support and an inner case are supported centrally within an outer case by radially inward extending hollow struts. An inner case carrying a diaphragm and seals which defines a vent cavity surrounding a bearing compartment. Air leaking past seals is collected in this vent cavity and flows through the hollow struts to be utilized for impingement cooling of the outer surface of the outer case.

Abstract: A mounting structure for the bearing in a hot part of a gas turbine engine that will permit thermal expansion of the bearing and its supporting ring with relation to the surrounding stationary and supporting part of the engine case without overstressing the several parts and still maintain concentricity of the bearing within this stationary support structure. This is accomplished by radially extending bosses on one part engaging slideably in radial recesses in the cooperating part.