Input Parameters
Formula Used
All angles are measured in degrees true. Wind direction is the direction the wind is blowing from. Course is the desired ground track.
- Angle between wind and course: θ = wind direction − course
- Crosswind component: Crosswind = W × sin(θ)
- Headwind / Tailwind component: Headwind = W × cos(θ)
- Wind Correction Angle (WCA): WCA = arcsin(Crosswind / TAS)
- Corrected heading: Heading = Course + WCA
- Ground speed: GS = TAS × cos(WCA) − Headwind
Positive crosswind values indicate wind from the right; negative values indicate wind from the left. Positive headwind values slow the aircraft, while negative values act as a tailwind.
How to Use This Calculator
- Enter the aircraft true airspeed in knots.
- Enter the forecast or observed wind speed in knots.
- Enter the wind direction, in degrees true, measured from north.
- Enter the desired course or track, in degrees true.
- Click Calculate to compute WCA, heading, and ground speed.
- Review headwind and crosswind components to assess wind impact.
- Use the CSV and PDF buttons to export your results.
Example Data Table
The following example illustrates a typical wind correction and ground speed calculation using realistic flight parameters.
| True Airspeed (kt) | Wind Speed (kt) | Wind Direction (°) | Course (°) | WCA (°) | Heading (°) | Ground Speed (kt) |
|---|---|---|---|---|---|---|
| 120 | 20 | 210 | 180 | +4.78 | 184.78 | 102.26 |
In-Depth Guide to Wind Correction and Ground Speed
Understanding wind correction angle fundamentals
Wind correction angle represents how many degrees you must turn into the wind to maintain the planned ground track. It directly depends on true airspeed, wind direction, and wind speed relative to the desired course.
Why ground speed matters in navigation
Ground speed determines how quickly you move across the earth’s surface. It controls estimated time en route, fuel planning, and waypoint crossing times. Even a modest tailwind or headwind can significantly change arrival time for longer flights.
Interpreting crosswind and headwind components
Crosswind component tells you how strongly the wind pushes sideways across the track. Headwind or tailwind component indicates how much the air mass slows or accelerates the aircraft along the route. These values help evaluate runway suitability and route efficiency.
Relating headings to true course and drift
The desired course is your intended ground track. After applying the wind correction angle, the resulting heading is what you actually fly. The difference between heading and course equals drift caused by the sideways component of the wind.
Using the calculator for flight planning
During planning, enter forecast winds aloft together with cruise airspeed and intended track. The calculator returns heading, correction angle, and ground speed. These values can be transferred to navigation logs, electronic flight bags, or kneeboard planning sheets.
Adjusting calculations in flight
Actual winds often differ from forecasts. You can update the calculator with observed groundspeed and drift based on position checks. Recomputing heading and correction angle helps refine estimates and maintain accurate navigation between waypoints when conditions change.
Limitations and best practice considerations
The model assumes steady, uniform wind and constant true airspeed. Turbulence, strong vertical motion, or rapid weather changes reduce accuracy. Combining this calculator with situational awareness, regular position fixes, and onboard navigation systems yields the most reliable results.
Frequently Asked Questions
Is wind correction angle measured left or right of course?
Wind correction angle is referenced from the desired course. A positive value usually indicates turning into a right crosswind, while a negative value means turning into a left crosswind to hold the same ground track.
Can I use magnetic headings instead of true?
The calculator works with any consistent reference. If you use magnetic course and magnetic wind direction, results remain valid. Just ensure all angles use the same reference frame when entering data and interpreting headings.
How accurate are results with strong winds?
Results remain mathematically valid for strong winds, but real world accuracy depends on how stable those winds are. Rapidly shifting or gusty conditions can change components faster than manual recalculations or updates.
Why does my ground speed differ from GPS readings?
Differences often come from inaccurate wind inputs, changing temperatures, or unaccounted altitude variations. GPS uses actual movement over the ground, while the calculator assumes steady conditions and constant true airspeed throughout the leg.
Should I round the computed heading?
Pilots usually round headings to the nearest whole degree for practical flying. Small rounding changes have minimal impact on short legs, but long segments may benefit from retaining one decimal place in detailed planning.
Can this calculator replace an E6B flight computer?
It can perform the same core wind calculations more quickly and with fewer manual steps. However, traditional tools and mental estimation techniques remain valuable backups if electronic devices fail during a flight.