An actuator system including a harmonic drive operable to drive a variable vane system of a gas turbine engine.

An actuator system including a harmonic drive operable to drive a variable vane system of a gas turbine engine.

An actuator system including a harmonic drive operable to drive a variable vane system of a gas turbine engine.

The present disclosure is directed to an auxiliary cleaning system for cleaning a gas turbine engine. The auxiliary cleaning system includes an external motoring source mechanically coupled to one or more engine shafts of the gas turbine engine. Thus, the external motoring source is configured to turn the one or more shafts. The auxiliary cleaning system also includes a cleaning apparatus configured to implement a cleaning procedure on the gas turbine engine while the external motoring source is turning the one or more shafts of the gas turbine engine.

A bowed rotor start mitigation system for a gas turbine engine is provided. The bowed rotor start mitigation system includes a controller operable to receive a vibration input indicative of an actual vibration level of the gas turbine engine and a speed input indicative of a rotor speed of the gas turbine engine. The controller generates a bowed rotor start mitigation request based on comparing the actual vibration level to a modeled vibration level at the rotor speed.

A bowed rotor start mitigation system for a gas turbine engine of an aircraft is provided. The bowed rotor start mitigation system includes a motoring system and a controller coupled to the motoring system and an aircraft communication bus. The controller is configured to determine at least one inferred engine operating thermal parameter from at least one aircraft-based parameter received on the aircraft communication bus. The motoring system is controlled to drive rotation of a starting spool of the gas turbine engine below an engine idle speed based on determining that the at least one inferred engine operating thermal parameter is within a preselected threshold.

A bowed rotor prevention system for a gas turbine engine of an aircraft is provided. The bowed rotor prevention system includes a bowed rotor prevention motor operable to drive rotation of a starting spool of the gas turbine engine through an engine accessory gearbox. The bowed rotor prevention system also includes a controller operable to engage the bowed rotor prevention motor and drive rotation of the starting spool until a bowed rotor prevention threshold condition is met or a bowed rotor prevention shutdown request to halt rotation of the starting spool is received.

A barring-tool system improving safety, speed, effectiveness, and number of personnel required for maintenance, repair, and inspection of large engines, generators, and turbines, providing controlled bidirectional rotation and locking of crankshafts during maintenance, and a method for maintenance of large engines, generators, and turbines using the barring-tool system.

A barring-tool system improving safety, speed, effectiveness, and number of personnel required for maintenance, repair, and inspection of large engines, generators, and turbines, providing controlled bidirectional rotation and locking of crankshafts during maintenance, and a method for maintenance of large engines, generators, and turbines using the barring-tool system.

A gas turbine engine, in particular an aircraft engine, includes: a turbine connected via an input shaft device to a gearbox device having a sun gear, a planet carrier having a plurality of planet gears attached thereto, and a ring gear, the sun gear is connected to the input shaft device, the planet carrier or the ring gear is connected to a propulsive fan via an output shaft device of the gearbox device, with a rear carrier bearing device radially between the planet carrier and a static structure on the input side of the gearbox device, an inter-shaft bearing system being positioned radially between the input shaft device and the planet carrier of the gearbox device.