Gas turbine engine starter reduction gear train with geared rotary actuator

An integrated starter and core-turning system for a gas turbine engine, the integrated starter and core-turning system comprising:

• a starter comprising a starter gear train that interfaces to an accessory gearbox of the gas turbine engine;
• and
• a reduction gearbox comprising:
• a reduction gear train operable to drive rotation of the starter gear train, the reduction gear train comprising:
• a starter interface gear operably connected to the starter gear train;
• a core-turning clutch operably connected to the starter interface gear;
• a geared rotary actuator comprising a primary planetary gear system, where the geared rotary actuator operably connected to the core-turning clutch;
• and
• a secondary planetary gear system operably connected to the primary planetary gear system and a core-turning input;
• and
• a mounting pad comprising an interface to couple a core-turning motor to the core-turning input of the reduction gear train.

A method of transmitting torque in a system for a gas turbine engine, the method comprising:

• transmitting torque output of a core-turning motor through a core-turning input of a reduction gear train of the system;
• transmitting torque at the core-turning input through a secondary planetary gear system and a primary planetary gear system of the reduction gear train, wherein the primary planetary gear system comprises a portion of a geared rotary actuator;
• transmitting torque from the geared rotary actuator through a starter interface gear operably connected to a core-turning clutch;
• and
• transmitting torque from the starter interface gear to drive rotation of a starter gear train that interfaces to an accessory gearbox of the gas turbine engine.