What is indicated by the vertical speed indicator (VSI)?

The vertical speed indicator (VSI) is a vital instrument in an aircraft that provides information about the rate of climb or descent. It indicates whether the airplane is climbing, descending, or maintaining a level altitude. This instrument shows the vertical speed in feet per minute and helps pilots understand the aircraft's performance during ascent or descent phases of flight.

Understanding the rate of climb or descent is essential for safe flight operations, as it allows pilots to make necessary adjustments to maintain a desired altitude, optimize fuel efficiency, or manage approach and landing procedures effectively. Proper utilization of the VSI aids in ensuring that the aircraft operates within safe limits and enhances overall situational awareness.