Crosswind Calculator

The Crosswind Formula

Both components come from basic trigonometry on the angle between the wind and the runway. Crosswind = wind speed x sin(wind angle) and headwind = wind speed x cos(wind angle), where the wind angle is the wind direction minus the runway heading. Wind 270° at 20 kts on runway 24 (240°) is 30° off the nose: 10 kts of crosswind and about 17 kts of headwind.

When the wind angle passes 90°, the cosine turns negative and the headwind becomes a tailwind component. The calculator labels this case explicitly, because tailwinds stretch takeoff and landing distance fast - most aircraft are limited to 10 kts of tailwind.

Clock Method: Crosswind Rule of Thumb

No calculator in the cockpit? Picture the wind angle as minutes on a clock face and take that fraction of the wind speed as crosswind:

From Components to a Heading

The crosswind component tells you how hard the wind pushes you sideways; the next step is working out how far to point the nose into it. Use the wind correction angle calculator to get the exact crab angle, heading to fly, and groundspeed for any true airspeed and desired track.