What component in an aircraft engine electrical system recharges the battery when the engine is running?

• A. To start the engine
• B. To recharge the battery and supply power when running
• C. To store energy
• D. To protect against short circuits

Answer: (B)

During engine operation, the engine-driven generator (often called the alternator) provides the electrical energy for the aircraft and recharges the battery. It converts mechanical power from the engine into electrical power and feeds the electrical bus while also maintaining the battery at the proper charge through its regulator. This is why the function described—recharging the battery and supplying power when the engine is running—is the best answer. The starter motor starts the engine, the battery stores energy, and protective devices like fuses or circuit breakers guard against short circuits.