Definition
A graphical chart used to determine the headwind and crosswind components of a reported wind relative to a runway. The pilot enters the chart with the angle between the wind direction and the runway heading, and the reported wind speed, then reads off two values: the headwind component (the portion of wind blowing straight down the runway) and the crosswind component (the portion blowing across it).
Plain English
A chart that breaks a reported wind into two parts: how much of it is blowing straight down the runway, and how much is blowing across it. Pilots use it to check whether the crosswind is within what the aircraft and the pilot can safely handle.
Context Anchor
Seen during takeoff and landing planning, especially when checking runway wind conditions against aircraft performance information.
Derivation
Crosswind means wind crossing the aircraft’s path. Headwind means wind blowing toward the front of the aircraft. Component comes from a Latin root meaning “put together,” and in this use it means one part of a larger wind direction broken into useful pieces.
Why Pilots Care
Reveals whether crosswind limits will be exceeded and adjusts expected takeoff or landing distance.
Intuition Check
Do not assume the full reported wind speed is the crosswind or headwind. The chart separates an angled wind into the part across the runway and the part along the runway.
Example Sentence 1
With the wind reported at 30 degrees off the runway at 20 knots, the crosswind and headwind component chart showed a 10-knot crosswind and a 17-knot headwind.
Example Sentence 2
Using the crosswind and headwind component chart showed a helpful headwind that shortened the calculated landing distance.