What is the normal rate of descent for airliners on final approach?
Airliners normally make instrument approaches, and published approaches normally require a glide path of about 3.0 degrees. Additionally, approaches are designed and executed to keep descent rates below 1000 feet per minute. The rate of descent required to stay on a glide path depends on the speed of the aircraft over the ground. For an airliner descending in calm winds at 130 knots true airspeed, a 3.0° glide path requires a descent rate of 688 fpm, which works out to 318 feet of descent per nautical mile of forward motion. A rough approximation can be obtained (for a 3.0° glide path) by simply multiplying the speed in knots by 5 to give a descent rate in feet per minute. This works at any speed. Often it’s not just the glide path that is important, but the distance to the airport as well. If the descent begins at the right altitude and distance from the runway, staying on the glide path as above will work fine. In other cases, the descent rate must be calculated based on the altitude
