A direct headwind
Course 090°, TAS 110 kt and wind 090° at 20 kt: ground speed 90.0 kt.
FLIGHT PLANNING
Ground speed calculator
Know your speed over the ground, with wind accounted for.
Ground speed97.6 ktHeading 277.2° magnetic
Course & wind
Live calculationSpeed units
Heading references: magnetic
Written METAR wind uses true north. Select the reference stated by your source; do not infer it from a runway number.
°
Your intended ground track°
Direction the wind is coming fromkt
Steady reported windkt
Your flight path, resolved.
LIVE RESULTSGround speed
97.6kt
Heading 277.2° magnetic
Correction angle7.2 ° right
Wind angle50.0 °
Maintain a heading of 277.2° to track 270.0° in this steady wind.
Report a calculation issue
Describe what you expected. This creates a report you can send to the site maintainer; it does not submit anything automatically.
A LITTLE THEORY
Make sense of your result.
Solve the wind triangle for ground speed while maintaining a desired course.
How to use this calculator
Enter your desired course, true airspeed, and wind-from direction and speed. The tool solves the heading required to maintain that course.
The formula
WCA = asin(crosswind / TAS) · GS = TAS × cos(WCA) − headwindθ is wind direction minus runway heading or course, normalized to −180° to 180°. V is wind speed. Results round to one decimal; calculations use full precision. Speed units are converted through knots.
PUT IT INTO PRACTICE01 02
Worked examples
A beam wind
Course 000°, TAS 100 kt and wind 090° at 20 kt: ground speed 98.0 kt with an 11.5° right correction.
A few common questions
Is ground speed TAS minus wind speed?+
Only for a direct headwind. A crosswind requires a heading correction and changes the forward airspeed component.
What if the wind is stronger than the aircraft?+
Some courses become impossible to maintain; the calculator reports that instead of an invalid result.
A planning aid. Always use your judgement.
Assumes constant wind and level flight. Course and wind must use the same heading reference. Actual wind varies along a route. This tool does not replace your aircraft operating handbook, official weather, regulations or pilot judgement.
Calculation transparency
Updated 11 September 2026. Automated checks cover the mathematical model; an independent aviation review is pending.
Reference: FAA aviation handbooks · Models and limitations