A starter supplemental lubrication system for a gas turbine engine is provided. The starter supplemental lubrication system includes a pneumatic starter operable to drive rotation of a rotor shaft of a gas turbine engine through an accessory gearbox. The pneumatic starter is configured to receive a primary lubricant flow at a first rotational speed range and receive a supplemental lubricant flow at a second rotational speed range that is less than the first rotational speed range. The starter supplemental lubrication system also includes a supplemental lubricant pump operable to supply the supplemental lubricant flow at the second rotational speed range. The supplemental lubricant pump is internal to the pneumatic starter.

A starter supplemental lubrication system for a gas turbine engine is provided. The starter supplemental lubrication system includes a pneumatic starter operable to drive rotation of a rotor shaft of a gas turbine engine through an accessory gearbox. The pneumatic starter is configured to receive a primary lubricant flow at a first rotational speed range and receive a supplemental lubricant flow at a second rotational speed range that is less than the first rotational speed range. The starter supplemental lubrication system also includes a supplemental lubricant pump operable to supply the supplemental lubricant flow at the second rotational speed range. The supplemental lubricant pump is internal to the pneumatic starter.

An aspect of the present disclosure is directed to a method for mitigating rotor bow in a turbo machine. The method includes rotating a rotor over a first period of time; discontinuing rotation of the rotor for a second period of time; and iterating, over an overall period of time, rotation of the rotor over the first period of time and discontinuing rotation of the rotor for the second period of time.

A turning system for rotating equipment, comprises a motor configured for speed control; a gear connected to the motor, the gear is further connected to the rotating equipment, the motor and gear are configured for rotating the rotating equipment at speeds less than the normal operating speed of the rotating equipment; and a controller configured to perform a method, wherein the method comprises a sequence of steps including, rotating the rotating equipment from a standstill an angular amount of rotation, stopping rotation after moving the angular amount of rotation, and maintaining the rotating equipment at a standstill for a period of time; and repeating the sequence of steps. By performing the sequence of steps after the rotating equipment comes to a standstill, bowing or sagging of the rotating equipment can be prevented, and the rotating equipment is ready to startup at anytime.

A method for starting a turbine engine in cold weather, including a starting system intended for rotating a drive shaft of the turbine engine. The method includes the following steps: a pre-starting step in which a first starting signal is generated to control the drive shaft in a first direction of rotation about a longitudinal axis and in a second opposite direction of rotation in an alternating manner; and a starting step in which a second starting signal is transmitted to the starting system in order for the latter to drive the drive shaft of the turbine engine in a normal direction of rotation and in which the drive shaft is rotated until a rotation speed that causes the turbine engine to start.

A method for starting a turbine engine in cold weather, including a starting system intended for rotating a drive shaft of the turbine engine. The method includes the following steps: a pre-starting step in which a first starting signal is generated to control the drive shaft in a first direction of rotation about a longitudinal axis and in a second opposite direction of rotation in an alternating manner; and a starting step in which a second starting signal is transmitted to the starting system in order for the latter to drive the drive shaft of the turbine engine in a normal direction of rotation and in which the drive shaft is rotated until a rotation speed that causes the turbine engine to start.

A gas turbine propulsion system includes a shroud that defines a fluid flow path. A gas turbine engine in the fluid flow path includes a compressor, a combustor downstream from the compressor, and a turbine downstream from the combustor. An electric generator in the fluid flow path includes a rotor coaxially aligned with the turbine. A propulsor is upstream from the gas turbine engine, and an electric motor is operably coupled to the propulsor to rotate the propulsor. The propulsor is rotationally isolated from the gas turbine engine so that the propulsor rotates independently from operation of the gas turbine engine.

A method of manufacturing a motoring system for a gas turbine engine including the steps of: forming a mechanical shaft fuse, the mechanical shaft fuse including a plurality of through holes; forming an outer housing; installing a reduction gear train into the outer housing, the reduction gear train having an input and an output; operably connecting an electric motor to the input; operably connecting a clutch to the output using the mechanical shaft fuse, the clutch in operation engages and disengages the reduction gear train; operably connecting a starter to the clutch, the starter having an output shaft; and operably connecting an accessory gearbox to the output shaft of the starter. The mechanical shaft fuse in operation shears when torque on the mechanical is greater than or equal to a selected value.

A method of manufacturing a motoring system for a gas turbine engine including the steps of: forming a mechanical shaft fuse, the mechanical shaft fuse including a plurality of through holes; forming an outer housing; installing a reduction gear train into the outer housing, the reduction gear train having an input and an output; operably connecting an electric motor to the input; operably connecting a clutch to the output using the mechanical shaft fuse, the clutch in operation engages and disengages the reduction gear train; operably connecting a starter to the clutch, the starter having an output shaft; and operably connecting an accessory gearbox to the output shaft of the starter. The mechanical shaft fuse in operation shears when torque on the mechanical is greater than or equal to a selected value.

An aircraft cabin blower system comprises a cabin blower including a compressor configured to provide air to a cabin of the aircraft; a variable drive system configured to drive the compressor and including an electric variator and a summing gearbox; and a main transmission configured, when operating in a blower mode, to receive mechanical power from a gas turbine engine and input mechanical power to the summing gearbox in a forward direction; and configured, when operating in a starter mode, to receive mechanical power from the summing gearbox and input mechanical power to the gas turbine engine. The aircraft cabin blower system further includes a first one-way rotation device adapted to permit free rotation of the main transmission in the forward direction and to prevent rotation of the main transmission in a reverse direction opposite to the forward direction.