The wind triangle is the central geometric construction of VFR navigation. It describes the interplay of three vectors:
The three vectors
| Vector | German | Meaning |
|---|---|---|
| Heading + TAS vector | Steuerkurs + TAS | What the aircraft does through the air (direction + speed relative to air mass) |
| Wind vector | Wind | Motion of the air mass relative to the ground — direction from which the wind blows, plus strength |
| Track + GS vector | Bahn + GS | What the aircraft does relative to the ground (direction + speed over ground) |
The vector equation
code
Heading (Heading + TAS) + Wind = Track (Track + GS)
Geometrically: the vector triangle closes when the three arrows are placed head-to-tail.
The two standard problems
Problem 1: Compute correction (given desired track, TAS, wind → find heading, GS)
- Known: true track (from chart), TAS (AFM at planned altitude/power), wind (forecast)
- Computed: Wind Correction Angle (WCA), true heading, ground speed
Problem 2: Determine wind in flight (given heading, TAS, track, GS → find wind)
- Known: current heading, TAS, observed track (from GPS or pilotage), GS (from ATO comparison)
- Computed: wind direction and speed
Sign convention
- WCA positive = crosswind from the right (heading must be corrected to the right, into the wind)
- WCA negative = crosswind from the left
Practical calculation
Use CRP-5 / E6B or a digital tool (SkyDemon, ForeFlight). PPL rule of thumb without a calculator:
code
WCA ≈ (crosswind component / TAS) × 60 (degrees)
GS ≈ TAS − headwind component
Where:
- Crosswind = wind × sin(α), Headwind = wind × cos(α)
- α = angle between track and wind direction