Calculate wind correction angle (WCA), ground speed, crosswind, headwind/tailwind components for aviation navigation. Includes wind direction comparison table.
Wind correction angle (WCA) is the angle a pilot must crab into the wind to maintain a desired ground track. Without correction, crosswinds push the aircraft off its intended course. The WCA is calculated from the wind speed, wind direction, airspeed, and heading using the wind triangle — the same calculation pilots have done with E6B flight computers since the 1930s.
The crosswind component determines the WCA: WCA = arcsin(crosswind/TAS). The headwind/tailwind component determines ground speed: faster with a tailwind, slower with a headwind. Both components are derived from the angle between the wind direction and the aircraft heading.
This calculator solves two problems: given a heading, find the resulting ground track and WCA; or given a desired course, find the heading to fly. The wind direction table shows how WCA and ground speed change as wind shifts through 360°, useful for understanding how wind patterns affect flight planning across different legs of a route.
It is useful when you want a fast wind-triangle answer without working through an E6B or drawing vectors by hand. Seeing crosswind, headwind, and ground speed together also makes route planning easier to explain. That is especially useful when comparing several legs or changing winds in preflight planning, where a small wind shift can change the heading you need to fly.
WCA = arcsin(Vw×sin(wind_angle)/TAS). Crosswind = Vw×sin(wind_angle). Headwind = Vw×cos(wind_angle). Ground speed = TAS×cos(WCA) − headwind.
Result: WCA = 7.2° left, GS = 119 kts, Crosswind = 15 kts from right
A 15-knot west wind hitting a northbound heading: full crosswind from the right. WCA = arcsin(15/120) = 7.2°. Crab 7° to the left. Ground speed barely affected since the wind is pure crosswind.
Wind correction angle comes from vector addition: the airplane moves through the air at true airspeed, while the air mass itself is moving over the ground. If the wind has a sideways component, the nose has to point into that drift so the resulting ground track stays on course.
Breaking the wind into crosswind and headwind or tailwind pieces makes the result easier to interpret. Crosswind determines how much crab angle is needed, and the along-track component determines whether the ground speed goes up or down. A pure crosswind changes heading but barely changes ground speed, while a direct headwind does the opposite.
Pilots usually run this calculation during preflight planning and again in flight when actual winds differ from the forecast. It is also helpful for comparing multiple route legs, because a wind that helps one leg can penalize the next. Keeping directions in true degrees and remembering that aviation winds are reported as the direction the wind is from will prevent the most common setup errors.
The angle between your heading and your ground track (course). You deliberately point the nose into the wind (crab) by this angle to maintain a straight ground track, so the aircraft does not drift off course.
It is the same thing: WCA = crab angle. The aircraft "crabs" sideways through the air to compensate for crosswind drift.
GPS shows ground track but does not compute the heading to fly. You still need WCA to know where to point the aircraft, and the E6B/WCA calculation is still required for FAA exams.
This calculator uses true directions. To convert to magnetic heading: subtract easterly variation, add westerly variation (variations west, magnetic best), then apply the wind correction angle.
Yes — winds aloft change speed and direction with altitude. Use winds at your planned cruise altitude. TAS also increases with altitude for the same IAS.
Aircraft-specific. For a Cessna 172: demonstrated crosswind component is 15 knots. For Boeing 737: typically 33 knots. Check your aircraft's POH.