Abstract: A method for synchronizing multiple generators includes positioning a pilot feature of a shaft of a first generator positioned at a first angular position that is substantially aligned with a first predetermined reference point located at a predetermined angular position relative to an axis, locking the shaft of the first generator at the first angular position, aligning a pilot feature of a first shaft of a second generator with a second angular position that is substantially aligned with a second predetermined reference point located at a position relative to the axis that is substantially equal to the predetermined angular position, calculating an angular difference between the two angular positions, and rotating a second shaft splined with the first shaft of the second generator about the axis in another direction, based on the calculated angular difference.

Abstract: A drivetrain for a multi-spool counter rotating gas turbine engine may include a lay shaft for connecting a power turbine shaft of the engine with a gas generator shaft of the engine when the drivetrain is in engine start mode. In normal operation mode, an actuator disengages the lay shaft, thereby allowing free and independent rotation of the power turbine shaft and the gas generator shaft.

Abstract: A synchronizing stationary clutch system for compression braking in a two spool gas turbine engine is provided by the present invention. The synchronizing stationary clutch system allows the two shafts of a two spool gas turbine engine to be reliably coupled at any given speed of either shaft. This coupling ability is useful to a gas turbine engine functioning in a land vehicle for the purpose of slowing the forward momentum of a rolling vehicle. The clutch system may also allow the use of auxiliary power from an electrical motor to start the engine.