What changes in GPS approach mode regarding the sensitivity on the CDI?

In GPS approach mode, the sensitivity of the Course Deviation Indicator (CDI) is designed to provide more precise guidance as the aircraft approaches the runway for landing. This adjustment in sensitivity enhances the pilot's situational awareness and allows for more accurate navigation.

When the aircraft transitions from en route to approach mode, the sensitivity of the CDI changes from a broader 1 nautical mile to a tighter 0.3 nautical mile. This shift means that the CDI will react more quickly and provide a more refined indication of the aircraft's position relative to the desired flight path, allowing for more precise adjustments during the final stages of the approach.

This increased sensitivity is especially important in terminal areas where accuracy is critical for safe landings, thus ensuring that pilots receive timely and relevant information to maintain the correct approach angle and alignment with the runway.