Free tool

Groundspeed and wind calculator

Enter a track, a true airspeed and a wind, and this calculator solves the triangle and draws it to scale beside the answer.

Groundspeed

177.7

Knots over the ground, which is 22.3 kt less than the true airspeed.

True heading

084

Point the nose here to make good the track. Drift is 6.1 degrees to starboard.

The working

  1. The wind is from 45 degrees at 30 kt, and you want to make good 90 degrees at 200 kt true.
  2. The wind pushes you to starboard, so the nose goes left of the track by the drift angle to cancel it. Drift 6.1 degrees.
  3. Heading = track 90 - 6.1 = 84 degrees true.
  4. Groundspeed = 177.7 kt, which is 22.3 kt less than the true airspeed, so the wind is a net headwind along this track.
200 kt177.7 kt30 kt
Heading and TAS Wind Track and groundspeed

Drawn to scale. The air vector runs along the heading for the length of the true airspeed, the wind vector runs from its tip in the direction the wind is blowing towards, and the side that closes the triangle is the track and the groundspeed.

Everything here is degrees TRUE. A track taken off a chart is true, a wind in a forecast is true, and the heading you fly on the compass is magnetic. Apply the local variation to the heading above before you steer it.

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