What does activating NAV mode accomplish during an instrument approach?

What does activating NAV mode accomplish during an instrument approach?

• A. NAV mode keeps current heading
• B. NAV mode joins the approach
• C. NAV mode switches to a backup navigation source
• D. NAV mode is not used on instrument approaches

Answer: (B)

Activating NAV mode uses the airplane’s navigation receiver to steer along the active approach course from the selected nav source. During an instrument approach, this lets the flight guidance capture and follow the published approach path—essentially joining the approach by tracking the final approach course toward the runway (such as the localizer or the GPS approach course). It isn’t about holding the current heading, and it isn’t about switching to a backup source—the NAV mode simply directs the aircraft to follow the chosen navigation signal to align with the approach.

Activating NAV mode uses the airplane’s navigation receiver to steer along the active approach course from the selected nav source. During an instrument approach, this lets the flight guidance capture and follow the published approach path—essentially joining the approach by tracking the final approach course toward the runway (such as the localizer or the GPS approach course). It isn’t about holding the current heading, and it isn’t about switching to a backup source—the NAV mode simply directs the aircraft to follow the chosen navigation signal to align with the approach.