Navigation
What the paper tests
The navigation paper covers the flight engineer's share of the navigation problem: dead reckoning, the wind triangle, chart and coordinate work, radio navigation aids (VOR/DME, NDB, GNSS, IRS), and the navigation performance requirements of oceanic and reduced-separation airspace.
Core rules
- Heading is where the nose points; track is the path over the ground; the difference is drift, produced by wind.
- Convert between true and magnetic using variation, and between magnetic and compass using deviation. Sign errors here cost marks all through the paper.
- The 1-in-60 rule: a 1 nm off-track error over 60 nm equals about 1° of angular error.
- In MNPS/RVSM and oceanic airspace, position reporting, ETA accuracy and contingency procedures are regulatory requirements, not good practice.
- IRS position drifts with time; updates from radio aids or GNSS are required for long sectors.
Worked example
Heading 090°T, TAS 200 kt, wind 180°/30 kt. The wind is at 90° to track, so all 30 kt is crosswind. Drift = arcsin(30/200) = 8.6°, so fly 090 − 8.6 = 081.4°T to hold track 090. Groundspeed = √(200² − 30²) = 197.7 kt. Note the direction of the correction: the wind from the south pushes you north, so you steer south of the intended track.
Traps
Applying the wind correction in the wrong direction, using TAS instead of groundspeed in ETA calculations, forgetting variation, and confusing magnetic heading with true track on a chart.