What happens if a pilot overrides an automatically selected GPS sensitivity during an approach?

Overriding the automatically selected GPS sensitivity during an approach typically results in the cancellation of the approach mode annunciation. This means that the system will no longer indicate that it is in approach mode, which is critical for ensuring proper vertical and lateral guidance during an approach.

In precision approaches, the GPS system adjusts its sensitivity to provide tighter guidance as the aircraft nears the runway. When a pilot overrides this feature, it disrupts the intended functionality of the approach, indicating to the pilot that they may not be receiving the necessary precision guidance. This is an important distinction as maintaining appropriate sensitivity is vital for safe and accurate landings within the constraints of the approach procedures.

While the other options may imply changes or errors that could occur, such as switching modes or resetting the system, the primary and immediate effect of overriding the sensitivity is the cancellation of the approach mode annunciation. This action can lead the pilot to be unaware of the improper guidance being provided, increasing the risk of navigating inappropriately during critical phases of flight.