Abstract: A nacelle and mounting arrangement for a high bypass ratio ducted fan aircraft engine mounted external to the aircraft main structure is disclosed. The nacelle and mounting arrangement isolate the engine from the adverse effects of certain aerodynamic forces acting on the nacelle by transferring substantially all of those forces directly from the nacelle to the aircraft and transferring substantially none of those forces to the engine. Various arrangements of the nacelle components which facilitate engine removal while avoiding the placement of nacelle component interfaces in highly stressed regions of the nacelle are also disclosed.

Abstract: A method for periodically restoring the blade tip to annular seal clearance in a gas turbine engine (10) includes incrementing (42a, 42b) the flow of external cooling air responsive only to an accumulated engine use parameter (58).

Abstract: A gas turbine engine cooling system has cooling air cooling in order, the first stage disk (50) and blades (22), the second stage vanes (24), and the second stage air seal (82). Air passes to the second stage vane from the rotor through a reaction nozzle (62) effecting a reaction stage adding energy to the rotor and cooling the air.

Abstract: A cooling system 46 for a turbofan gas turbine 10 is disclosed. Various construction details which increase the effectiveness of a heat exchanger 48 located in the secondary flow path 24 are developed. In one embodiment, the cooled air is used for protecting a bearing compartment.

Abstract: A cooling system 46 for a turbofan gas turbine engine 10 is disclosed. Various construction details which increase the effectiveness of a heat exchanger 70, 76, 112 are disclosed. In one embodiment, a rotor shaft 98 is used to pressurize buffer air for a bearing compartment 40.

Abstract: A cooling system 46 for a turbofan gas turbine engine 10 is disclosed. Various construction details which increase the effectiveness of a heat exchanger 70, 76, 112 are disclosed. In one embodiment, a rotor shaft 98 is used to pressurize buffer air for a bearing compartment 40.

Abstract: A cooling system 46 for a turbofan gas turbine 10 is disclosed. Various construction details which increase the effectiveness of a heat exchanger 48 located in the secondary flow path 24 are developed. In one embodiment, the cooled air is used for protecting a bearing compartment.

Abstract: A multistage turbine construction in which the cooling flow to the turbine rotor is controlled by cooperating sealing elements carried respectively by the row of vanes and by the rotor with the sealing surface carried by the vanes, the stationary surface being an outwardly sealing surface and the fins cooperating therewith carried by the rotor extending radially inward such that as the turbine rotor cools down during reduced power operation the sealing effect will be increased to reduce the flow of cooling fluid over the rotor surface.

Abstract: A coolable rotor stage assembly 14 of the turbine 10 of an axial flow gas turbine engine is disclosed. A cavity 18 for purge air is adjacent the rotor disk 22. A nozzle 34 for metering the flow of cooling air through the rotor blade, for forming a jet of high velocity air and for directing the cooling air from the root of the rotor blade inhibits recirculation, retards formation of the radial pumping boundary layer, decreases the thickness t of the radial pumping boundary layer and does work on the rotor blade.