Abstract: The invention is related to a fastener assembly of the kind used to secure a gas turbine engine rotor disc assembly on a shaft in a situation which otherwise would required the use of a trapped nut. It thereby removes a design constraint limiting bore diameter of the disc assembly to permit access to a securing nut on the shaft, and avoids the use of a trapped nut. One of the rotors hubs is adapted to be mounted on the shaft and the securing nut is engaged with a thread on the shaft to trap the hub. In the improvement of the invention the hub is provided with an axial keyway through which the securing nut is passed into the limited access space. Once the shaft is engaged with the hub the nut is then engaged with the thread on the shaft and tightened using a special tool extending through the centre of the shaft. The tool is withdrawn after use. The nut may be undone and retrieved in an opposite operation.

Abstract: The invention is related to a fastener assembly of the kind used to secure a gas turbine engine rotor disc assembly on a shaft in a situation which otherwise would required the use of a trapped nut. It thereby removes a design constraint limiting bore diameter of the disc assembly to permit access to a securing. nut on the shaft, and avoids the use of a trapped nut. One of the rotors hubs is adapted to be mounted on the shaft and the securing nut is engaged with a thread on the shaft to trap the hub. In the improvement of the invention the hub is provided with an axial keyway through which the securing nut is passed into the limited access space. Once the shaft is engaged with the hub the nut is then engaged with the thread on the shaft and tightened using a special tool extending through the centre of the shaft. The tool is withdrawn after use. The nut may be undone and retrieved in an opposite operation.