Crosswind Component Calculator

How it is calculated

The tool takes the angle between the wind and the runway heading, θ = wind direction − runway heading (degrees), and resolves the wind speed V into two parts: crosswind = |V × sin θ| and head/tail = V × cos θ. A positive cosine is a headwind; a negative one is a tailwind, and the tool prints the size of that component together with a Headwind or Tailwind label. Wind speed keeps whatever unit you enter (knots in, knots out), and both components are shown to two decimals without a unit. Direction and heading are in degrees, and a negative wind speed gives no result. The tool does not look up runway numbers and ignores gusts, so run it again with the gust speed if you need the worst case.

Common mistakes

• Entering the runway number (25) instead of its heading in degrees (250). The tool uses the number as degrees and gives a very different answer: 19.32 crosswind and a tailwind for the same wind.
• Mixing magnetic and true directions. Tower and ATIS winds are usually magnetic, while some forecasts are true, so make sure the wind direction and the runway heading use the same reference.
• Entering the direction the wind is blowing towards. Reported wind direction is where the wind comes from.
• Using the steady wind when the gusts are higher; the crosswind limit should be checked against gust speed too.
• Reading the head/tail figure as positive for both cases. The value is always shown without a sign, so check the label to see whether it is a headwind or a tailwind.