Which component is on the APU accessory gearbox?

Which component is on the APU accessory gearbox?

• A. Speed sensor
• B. Oil pump and lubrication module
• C. Fuel control unit and high-pressure fuel pump
• D. Generator

Answer: (B)

The APU accessory gearbox is the drive hub for the little systems the APU needs to run and stay healthy. The oil pump and lubrication module are placed on this gearbox so the lubrication system can be driven directly by the same shaft that powers the other accessories. This arrangement guarantees oil pressure and circulation to the APU’s bearings and gears from startup through shut-down, keeping everything properly lubricated without extra routing complexity. The other items are not typically mounted on the APU accessory gearbox in standard configurations: a speed sensor is a monitoring device, not a driven accessory; the fuel control unit and high-pressure fuel pump belong to the fuel delivery system and are not part of the lubrication drive; and while generators are common on many accessory gearboxes, the question here points to the lubrication system as the specific AGB-mounted component.

The APU accessory gearbox is the drive hub for the little systems the APU needs to run and stay healthy. The oil pump and lubrication module are placed on this gearbox so the lubrication system can be driven directly by the same shaft that powers the other accessories. This arrangement guarantees oil pressure and circulation to the APU’s bearings and gears from startup through shut-down, keeping everything properly lubricated without extra routing complexity.

The other items are not typically mounted on the APU accessory gearbox in standard configurations: a speed sensor is a monitoring device, not a driven accessory; the fuel control unit and high-pressure fuel pump belong to the fuel delivery system and are not part of the lubrication drive; and while generators are common on many accessory gearboxes, the question here points to the lubrication system as the specific AGB-mounted component.