Navigation definitions
Path and pointing
| Term | Meaning |
|---|---|
| Track | Path over the ground |
| Required track | Planned track (TP 1102) |
| Heading | Where nose points |
| Drift | Angle between heading and track opened by crosswind |
| Wind correction angle (WCA, crab) | Heading turned into wind to cancel drift and hold track |
| Airspeed | Indicated airspeed (IAS) (AC 100-001 glossary) |
| Bearing | Direction of one point from another, measured from north |
| Great circle | Shortest distance between two points on earth's surface |
Drift is named by track's side of heading:
- Track right of heading = drift right (PHAK ch.16; wind from left pushes aircraft right).
- Track left of heading = drift left (TP 1102 "track made good ... 7 degrees left of the required track").
Trap: calling heading "track". Wind sets them apart.
References
- AC 100-001 glossary
- TP 1102
- PHAK glossary: great circle route