A method of operating a turbine engine that includes actuating a starter motor of the turbine engine such that a motoring speed of the turbine engine increases, and actuating a plurality of variable stator vanes of the turbine engine such that the plurality of variable stator vanes are at least partially open to control the motoring speed of the turbine engine.

A method of operating a turbine engine that includes actuating a starter motor of the turbine engine such that a motoring speed of the turbine engine increases, and actuating a plurality of variable stator vanes of the turbine engine such that the plurality of variable stator vanes are at least partially open to control the motoring speed of the turbine engine.

A system and method for starting an aircraft turbine engine includes a primary starting subsystem and a secondary starting subsystem. The primary starting subsystem is coupled to a shaft of the aircraft turbine engine and has a dedicated power source. The secondary starting subsystem is also coupled to the shaft of the aircraft turbine engine and has a shared power source. A controller controls the operation of the primary starting subsystem and the secondary starting subsystem while starting the aircraft turbine engine. The primary starting subsystem may be an Auxiliary Power Unit coupled to an Air Turbine Starter. The secondary starting subsystem may be a Starter Generator coupled to a battery also used to power the Emergency Hydraulic System. The primary starting subsystem is always operated at full power during starting while the secondary starting subsystem is preferably operated in a sequence of different power levels.

An air turbine starter that includes a housing. The housing can circumscribe a turbine coupled that is coupled to a gear train in a gear box via a drive shaft. The gear train can couple to an output shaft via at least a carrier. The air turbine starter can include at least a first bearing assembly and a second bearing assembly to rotatably support one or more of the drive shaft, the carrier, or the output shaft.

An air turbine starter that includes a housing. The housing can circumscribe a turbine coupled that is coupled to a gear train in a gear box via a drive shaft. The gear train can couple to an output shaft via at least a carrier. The air turbine starter can include at least a first bearing assembly and a second bearing assembly to rotatably support one or more of the drive shaft, the carrier, or the output shaft.

A system and a method for the automatic starting of the engines of a twin-engine aircraft. When a first engine is made by the pilots of the aircraft to follow an automatic starting procedure, this engine follows the conventional four-phase starting cycle. The rotor of the high-pressure stage of the second engine is spun up for a predetermined duration and to a speed that is substantially constant and less than the nominal value during the starting cycle for the first engine. Once the starting cycle for the first engine is complete, the second engine is made by the pilots of the aircraft to follow an automatic starting procedure. The starting cycle for the second engine comprises just three phases.

A system and a method for the automatic starting of the engines of a twin-engine aircraft. When a first engine is made by the pilots of the aircraft to follow an automatic starting procedure, this engine follows the conventional four-phase starting cycle. The rotor of the high-pressure stage of the second engine is spun up for a predetermined duration and to a speed that is substantially constant and less than the nominal value during the starting cycle for the first engine. Once the starting cycle for the first engine is complete, the second engine is made by the pilots of the aircraft to follow an automatic starting procedure. The starting cycle for the second engine comprises just three phases.

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 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 system for starting a gas turbine engine of an aircraft is provided. The system includes a pneumatic starter motor, a discrete starter valve switchable between an on-state and an off-state, and a controller operable to perform a starting sequence for the gas turbine engine. The starting sequence includes alternating on and off commands to an electromechanical device coupled to the discrete starter valve to achieve a partially open position of the discrete starter valve to control a flow from a starter air supply to the pneumatic starter motor to drive rotation of a starting spool of the gas turbine engine below an engine idle speed.