Abstract: To eliminate stress peaking at the bearing surface interface of the blade and disk slot dovetails in a gas turbine engine, the slot dovetail in undercut to remove disk material from contact with the blade dovetail radially inner edges where surface stress peaking would otherwise occur. The undercut contour radially inward of the blade dovetail is determined by analysis based on each engine design such as to achieve a substantially uniform distribution of surfaces stress along the dovetail slot fillet radius.

Abstract: A coolant pressure regulating appartus having a predetermined number of coolant pressure regulating valves which rotate against a spring bias to divert coolant flow and excess pressure from the coolant air fan duct into the engine core exhaust flow. The pressure regulator valve regulates the pressure within a closed cavity suppressor to the pressure level within the core without any affect upon the upstream fan duct pressure.

Abstract: A segmented damper is provided with a lower dovetail portion which is insertable into a dovetail slot for radial retention and which is engageable on its face by a blade retainer for axial retention, such that the damper is pivotable in an axial plane. The damper upper portion has on its one side a flange for engaging the blade shank rail and on its other side a flange for shifting the damper center of gravity axially outward from the lower pivot point. Centrifugal force, occasioned by rotation of the disk and damper, then causes the damper to pivot and impart an axial force against the blade to thereby dampen vibrations.

Abstract: A bore vane assembly is adapted to be received within the annular passage formed between two axially displaced turbine disc halves so as to provide axial columnar support therebetween during high centrifugal loading. The bore vane assembly includes a plurality of axially extending vanes which provide the required support and which also serve to pump cooling fluid from a plenum into the turbine disc.