Definition
A reference table that shows the rate of descent in feet per minute required to maintain a specific glide path angle at a given groundspeed. Pilots cross-reference their groundspeed against the published glide slope angle (typically 3°) to find the vertical speed needed to stay on the glide path during an instrument approach.
Plain English
A small chart that tells you how fast you need to come down, in feet per minute, to stay on the correct approach path. You look up your groundspeed and read across to find the number to fly on your vertical speed indicator.
Context Anchor
Seen in instrument approach training and approach planning, especially when estimating the descent rate needed on final approach.
Why Pilots Care
Using the correct rate of descent keeps the aircraft on the published glide path, ensuring obstacle clearance and a stabilized approach to the runway in instrument conditions.
Grounding Statement
On the same descent path, a faster airplane must descend more feet each minute than a slower airplane.
Intuition Check
A Rate of Descent Chart is not a fixed command for every approach. It is an estimate based on the chosen descent path and the airplane’s speed over the ground.
Example Sentence 1
At 90 knots groundspeed on a 3° glide path, the rate of descent chart shows the pilot should descend at about 480 feet per minute.
Example Sentence 2
Before starting the approach, the crew used the rate of descent chart to pre-select the vertical speed needed for the current wind and groundspeed.