What instruments can be used to determine that the alternator has failed?

What instruments can be used to determine that the alternator has failed?

• A. Speedometer and compass
• B. Altimeter and vertical speed indicator
• C. Ammeter and low-voltage warning light
• D. Horizon indicator and attitude indicator

Answer: (C)

The correct answer identifies the instruments associated with monitoring the electrical system in an aircraft. An ammeter provides a direct reading of the electrical current being produced by the alternator. If the alternator fails, the ammeter will show a discharge rather than a charge, indicating a problem with the alternator's ability to generate power. Additionally, the low-voltage warning light serves as a crucial visual alert. When the alternator fails, and the battery begins to supply power without being recharged, the voltage can drop below a safe threshold, illuminating this warning light to indicate an electrical issue requiring immediate attention. The other choices do not provide relevant information about the alternator's status. For instance, a speedometer and compass, an altimeter and vertical speed indicator, or a horizon indicator and attitude indicator are primarily concerned with flight performance and navigation rather than electrical system assessments. Thus, monitoring the ammeter and low-voltage warning light is essential for pilots to detect alterations in the electrical system’s performance effectively.

The correct answer identifies the instruments associated with monitoring the electrical system in an aircraft. An ammeter provides a direct reading of the electrical current being produced by the alternator. If the alternator fails, the ammeter will show a discharge rather than a charge, indicating a problem with the alternator's ability to generate power.

Additionally, the low-voltage warning light serves as a crucial visual alert. When the alternator fails, and the battery begins to supply power without being recharged, the voltage can drop below a safe threshold, illuminating this warning light to indicate an electrical issue requiring immediate attention.

The other choices do not provide relevant information about the alternator's status. For instance, a speedometer and compass, an altimeter and vertical speed indicator, or a horizon indicator and attitude indicator are primarily concerned with flight performance and navigation rather than electrical system assessments. Thus, monitoring the ammeter and low-voltage warning light is essential for pilots to detect alterations in the electrical system’s performance effectively.