Instrument Rating Checkride Practice Test

The Vertical Speed Indicator (VSI) is the instrument that primarily indicates the aircraft's climb or descent rate. It provides real-time feedback to the pilot regarding how quickly the aircraft is ascending or descending, typically expressed in feet per minute. This information is crucial during various phases of flight, especially during takeoff and landing when pilots need to maintain controlled ascent or descent rates.

The VSI measures the change in air pressure as the aircraft moves upward or downward, providing an intuitive understanding of vertical performance. By monitoring the VSI, a pilot can make necessary adjustments to the aircraft's attitude or power settings to ensure safe and efficient climbs or descents.

In contrast, the altimeter measures altitude but does not provide a rate of change; it indicates the height of the aircraft above mean sea level. The airspeed indicator displays the aircraft's speed through the air, which is important but does not directly relate to vertical movement. The attitude indicator shows the aircraft's orientation relative to the horizon, which is essential for maintaining controlled flight but does not offer specific information about climb or descent rates. Therefore, the VSI is crucial for monitoring vertical performance during instrument flight.