The N1 gear train drives which two components?

• A. Hydraulic pump and fuel pump
• B. Starter generator and oil pump
• C. Starter motor and alternator
• D. Engine cooling fan and oil cooler

Answer: (B)

The N1 gear train powers the accessory drive gearbox, which supplies mechanical drive to essential engine accessories. This gearbox is driven by the N1 spool, so components connected to it get spinning from the same source. The two components that are typically driven by this gear train are the starter generator and the oil pump. The starter generator uses the gearbox to start the engine and then acts as a generator to provide electrical power. The oil pump needs to run continuously to circulate lubrication through the engine, and it is conveniently powered off the same accessory drive. Other options aren’t the standard pair connected to the N1 drive in this context, since those components aren’t the primary accessories driven by the N1 gear train in the common configuration.