Definition
On an electronic flight display, the rate at which the airplane is climbing or descending, shown in feet per minute on the vertical speed indicator (VSI) tape or pointer. A trend indicator alongside it predicts where the vertical speed will be in six seconds if the current control input is maintained, allowing the pilot to anticipate and stop a climb or descent precisely.
Plain English
How fast the airplane is going up or down, measured in feet per minute. On a glass cockpit, a small marker also shows where that rate is heading next, so the pilot can see the change coming before it happens.
Context Anchor
Seen on an electronic flight display when monitoring trend indicators during instrument flight.
Why Pilots Care
Holding a target vertical speed -- and stopping a climb or descent at the right altitude -- is a core instrument flying skill. The trend portion lets the pilot lead the level-off rather than chase it, which keeps altitudes within tolerance during instrument approaches and ATC-assigned climbs and descents.
Grounding Statement
If the number shows a climb, the aircraft is gaining altitude; if it shows a descent, the aircraft is losing altitude.
Intuition Check
Do not read “speed” here as forward speed through the air. Vertical speed rate is about movement up or down, not how fast the airplane is moving ahead.
Example Sentence 1
Passing through 4,500 feet, she reduced the vertical speed rate to 500 feet per minute to level off smoothly at 5,000.
Example Sentence 2
During the approach, small pitch adjustments kept the vertical speed rate at the target 800 feet per minute descent.