Which component both starts the engine and recharges the battery during operation?

• A. Starter generator
• B. Battery
• C. GCU
• D. EPU

Answer: (A)

The starter generator is designed to do both jobs: start the engine and then recharge the battery once the engine is running. It begins as a motor, using power from the battery to turn the engine over until ignition occurs. After the engine starts, it automatically switches to generating mode, providing electrical power to the aircraft systems and recharging the battery as the engine runs. This dual role is what makes it the best answer, since it handles starting and charging in one unit. The other components don’t perform both tasks: the battery alone can’t start the engine and doesn’t continuously recharge itself; the GCU is a controller, not the power source for starting or charging; the emergency power unit provides power only in emergencies.