Navigation: General, Radio and Instrument
General navigation
Know the Earth's shape and the graticule, latitude and longitude, great circles and rhumb lines, and how to convert between true, magnetic and compass headings (variation and deviation). Understand the triangle of velocities: true airspeed, wind velocity and track combine to give heading and groundspeed. Time, fuel and distance calculations must be fluent.
Radio and instrument navigation
Know the principles of VOR (radial, CDI, TO/FROM), NDB/ADF (relative bearing, QDM/QDR), DME (slant range), ILS (localiser, glide path, markers) and GNSS (RAIM, waypoints, approach minima). Understand the difference between a radial and a bearing, and between track and heading. Instrument flight questions test procedure turns, holding patterns (entries: direct, parallel, teardrop) and the standard turn rate of 3° per second.
Traps
A common trap is confusing inbound and outbound headings in a hold, or forgetting wind correction in the hold. Another is using magnetic variation with the wrong sign. In VOR questions, remember the CDI senses the selected course, not the aircraft heading.
Worked example / rule of thumb
Rule of thumb: 1 in 60 rule - a 1° error over 60 nm puts you 1 nm off track. For holds, the entry is determined by the aircraft's heading relative to the inbound course: within 70° either side is direct; beyond 110° is parallel; the sector between is teardrop.
Study strategy
Draw the triangle of velocities for every wind problem and label each vector before calculating.