Cessna 172 Systems Practice Test - Prep, Study Guide & Practice Questions

In the Cessna 172, the primary power source for the electrical system is the alternator. The alternator is responsible for generating electrical power while the engine is running, supplying electricity to the aircraft's electrical systems and recharging the battery simultaneously. This system ensures consistent power delivery for essential functions like avionics, lighting, and other electrical devices throughout the flight.

While the battery provides an initial power source for starting the engine and may provide backup power, it primarily acts as a support system rather than the main source during normal operations. The generator, which is a different type of electrical power source that produces electricity through mechanical energy, is not utilized in the Cessna 172, as this model is equipped with an alternator instead. An inverter is also not applicable here since it is used to convert DC power to AC power, which is not the primary need for the Cessna 172's electrical system. Thus, the alternator plays a crucial role in maintaining the aircraft's electrical integrity during operation.