What happens to the VSI's sensitivity when displaying small rates of climb or descent?

The vertical speed indicator (VSI) is designed to measure and display the rate of climb or descent of an aircraft. When it comes to displaying small rates of climb or descent, the sensitivity of the VSI actually increases. This occurs because the instrument is calibrated to provide a more precise indication of these small changes in vertical speed, allowing pilots to make finer adjustments to their ascent or descent rates.

The increased sensitivity is particularly important during critical phases of flight, such as landing or takeoff, where even a slight change in altitude can have significant implications for safety and performance. By being more responsive to minor changes, the VSI helps provide immediate feedback to the pilot, facilitating better control of the aircraft's vertical movement.

In contrast, other options suggest that the VSI either remains constant, becomes less sensitive, or inaccurate, which does not align with the instrument's function to provide precise feedback on small rate changes.