Navigation: Dead Reckoning, Charts and Radio Aids
What you must know
Navigation questions cover chart reading, the triangle of velocities, dead reckoning, magnetic variation and deviation, time, fuel and radio navigation aids. Understand true, magnetic and compass headings, and the sequence true → apply variation → magnetic → apply deviation → compass. Know how to compute heading, groundspeed and drift from true airspeed, wind direction and wind speed. Be able to read a chart for airspace, obstacles, magnetic variation and scale. Understand VOR, DME, ADF/NDB and GNSS basics, and the meaning of radial versus bearing. Know the 1-in-60 rule for track error corrections.
Traps in questions
- Adding variation when it should be subtracted - east is least, west is best.
- Confusing a VOR radial (from the station) with a bearing (to the station).
- Using true airspeed as groundspeed when wind is present.
- Mixing nautical miles, statute miles and kilometres on a chart.
Worked rule of thumb
Apply the 1-in-60 rule: track error in degrees equals distance off track divided by distance flown, multiplied by 60. Example: 4 NM off after 40 NM gives 4 ÷ 40 × 60 = 6° of track error. Correct the heading by that amount and double it to regain track (the "double track error" method).
Study approach
Practise one full navigation plan: true heading, wind correction, magnetic heading, compass heading, groundspeed, time and fuel.