The gearbox housing and cover, gas producer gear train, and power turbine gear train are components of which assembly?

The gearbox housing and cover, gas producer gear train, and power turbine gear train are components of which assembly?

• A. Fuel control assembly
• B. Turbine engine assembly
• C. Accessory gearbox assembly
• D. Starter motor assembly

Answer: (C)

The thing these parts belong to is the accessory gearbox assembly. The accessory gearbox is the housing that contains the gear trains and shafts that drive the engine’s external accessories (like pumps, generators, and starters). The gas producer gear train takes power from the gas generator portion of the engine to run the gearbox, while the power turbine gear train provides drive from the turbine side when needed. Together, they transfer the engine’s rotating motion to the accessories at the correct speeds and torques. Other options don’t fit because they refer to parts of the engine’s main systems (fuel control, the entire turbine engine, or just the starter motor) rather than the dedicated gearbox that houses these drive trains and their housing.

The thing these parts belong to is the accessory gearbox assembly. The accessory gearbox is the housing that contains the gear trains and shafts that drive the engine’s external accessories (like pumps, generators, and starters). The gas producer gear train takes power from the gas generator portion of the engine to run the gearbox, while the power turbine gear train provides drive from the turbine side when needed. Together, they transfer the engine’s rotating motion to the accessories at the correct speeds and torques.

Other options don’t fit because they refer to parts of the engine’s main systems (fuel control, the entire turbine engine, or just the starter motor) rather than the dedicated gearbox that houses these drive trains and their housing.