What is the sensitivity change of the Course Deviation Indicator (CDI) in GPS approach mode?

In GPS approach mode, the sensitivity of the Course Deviation Indicator (CDI) indeed changes from 1 nautical mile (NM) to 0.3 NM. This sensitivity adjustment is important because it enhances the precision of lateral guidance as the aircraft approaches the runway during an instrument approach.

When operating in GPS approach mode, a more sensitive CDI allows pilots to maintain better situational awareness and assists in making finer adjustments to the aircraft's flight path as it closes in on the intended approach course. The transition from a 1 NM sensitivity, which is suitable for navigating at greater distances from the runway, to a 0.3 NM sensitivity is particularly critical during the final approach phase. This shift enables pilots to follow the precise lateral guidance needed to ensure a safe and accurate approach to landing.

This increased sensitivity helps improve navigation accuracy and assists pilots in aligning with the runway more effectively while also complying with required minimums during an instrument approach.