Comprehensive Study Guide
Wind Correction Angle (WCA) Study Guide
Master vector geometry, True Course vs True Heading, crab angles, and magnetic variation steering.
Editorially reviewed by the AviCalculator team
1. Vector Mechanics Fundamentals
When an aircraft navigates inside a crosswind air mass, lateral wind force pushes the airframe off course. The Wind Correction Angle (WCA) (or crab angle) is the exact angular rotation pointed into the wind required to maintain intended ground track.
- True Course (TC): Intended geographic flight line drawn on sectional chart.
- True Heading (TH): Direction aircraft nose points: TH = TC ± WCA.
- Magnetic Variation: Angular spread between True North and Magnetic North ("East is Least, West is Best").
2. E6B & Trigonometric Formula
WCA = arcsin [ ( WindSpeed × sin( WindDir - Track ) ) / TrueAirspeed ]
3. Practical Example
If TC is 090°, wind is from 030° at 25 kts, and TAS is 120 kts. Wind hits from front-left. You must steer a negative (left) crab angle (~10° left) resulting in a True Heading of 080°.
Test Your Knowledge
You've reviewed the theory. Now apply it to real FAA/EASA checkride questions to verify your understanding.