Independent educational reference. Not affiliated with GACA — always verify against the official source, gaca.gov.sa.

Flight Tools · Top of Descent

Top of Descent

Top of descent calculator

Know where to start down. From your cruise and target altitudes, a descent rate and groundspeed, this gives the distance and time to the point where the descent must begin.

A still-air planning estimate. Wind, ATC and the published arrival all change the real top-of-descent point — fly the cleared profile.

The descent

Groundspeed, not airspeed — the distance is over the ground.

ft
ft
fpm
kt

Result

Start descent
before the target point
Time to descend
Altitude to lose
Descent gradient