Tools / Descent planner

Descent planner

Top of descent distance and the vertical speed for your groundspeed.

Current altitude (ft)

Target altitude (ft)

Groundspeed (kt)

Descent path (°)

Slow-down allowance (NM)

Distance = altitude to lose ÷ (6,076 × tan angle). Vertical speed = groundspeed × 101.3 × tan angle, about groundspeed × 5 on a 3° path. The quick check is the 3-to-1 rule: 3 NM for every 1,000 ft. Add the slow-down allowance if you must decelerate (for example to 250 kt below 10,000 ft).

For flight simulation only. Always follow your aircraft's procedures and the published charts.