Abstract: Methods, apparatus, and systems for trapped rotatable weights to improve rotor balance are disclosed. An example apparatus includes a lock nut; a rotor assembly; a channel defined by the lock nut and the rotor assembly, the channel wrapped circumferentially around a geometric center of the rotor assembly; and a weight trapped within the channel.

Abstract: Methods, apparatus, and systems for trapped rotatable weights to improve rotor balance are disclosed. An example apparatus includes a lock nut; a rotor assembly; a channel defined by the lock nut and the rotor assembly, the channel wrapped circumferentially around a geometric center of the rotor assembly; and a weight trapped within the channel.

Abstract: A method for redistributing an area of residual stress around a machined central aperture in an engine component. The method includes changing tensile stress to compressive stress at an area circumscribing the machined aperture. The method can be applied to, for example, a forged engine component such as a rotating disk or an impeller part for a gas turbine engine.

Abstract: A rotary position sensing system and method are disclosed, including a shaft comprising an offset mounting hole, and a magnet having a magnetic field that is magnetized across an axis of the magnet, wherein the magnet is mounted to the shaft at the offset mounting hole and oriented to the offset mounting hole. One or more Hall-effect sensing elements can also be located a fixed distance from the magnet to provide a linear output signal proportional to the magnetic field of the magnet and the angular position of the shaft, thereby providing an angular position measurement of a device mated to the shaft.