Abstract: A bladed disc system for a turbine engine having a disk portion and a plurality of blade portions which are associated with a stator section and an intercavity sealing portion, disc portion shaped such that blade portions are able to fit within firtree slot in disc portion, blade portion having aerofoil section and root section, aerofoil section having portion shaped such that they extend proximate to intercavity sealing portion, disc portion extending from portion that connects with drum to outer edge at which blade portions are connected with disc portion having width transition region in which thickness of disc increases from point at which disc connects to drum to outer edge at which it holds blade portions, and wherein width transition region has curved width transition region with radius r, and an overhanging portion which extends into the intercavity spacing between the width transition region and the intercavity sealing portion.

Abstract: A bladed disc system for a turbine engine, the bladed disk portion comprising a disk portion and a plurality of blade portions, the disc portion being shaped such that the blade portions are able to fit within fir tree slot in the disc portion, the blade portion comprising an aerofoil section and a root section, with the root section comprising a fir tree profile and a skirt portion and wherein the skirt portions of adjacent blades form an opening that has a maximum separation of between 1-50% of the maximum skirt opening width.

Abstract: A bladed disc system for a turbine engine having a disk portion and a plurality of blade portions which are associated with a stator section and an intercavity sealing portion, disc portion shaped such that blade portions are able to fit within firtree slot in disc portion, blade portion having aerofoil section and root section, aerofoil section having portion shaped such that they extend proximate to intercavity sealing portion, disc portion extending from portion that connects with drum to outer edge at which blade portions are connected with disc portion having width transition region in which thickness of disc increases from point at which disc connects to drum to outer edge at which it holds blade portions, and wherein width transition region has curved width transition region with radius r, and an overhanging portion which extends into the intercavity spacing between the width transition region and the intercavity sealing portion.

Abstract: A labyrinth seal having a land that comprises an array of polygonal cells, wherein at least 50% of the cells include a planar wall that subdivides the cell. The seal reduces seal leakage and can reduce specific fuel consumption of gas turbine engines that include such seals.