ATPL Navigation study guide
ATPL Navigation · Work through your exam, one topic at a time.
Navigation is one of the core technical subjects of the ATPL ground syllabus, and it carries substantial weight because it underpins almost everything a pilot does in flight: knowing where the aircraft is, where it is going, and how long it will take to get there. The subject is examined as a multiple-choice paper covering the form of the Earth and coordinate systems, terrestrial magnetism and compasses, chart projections, the triangle of velocities and dead reckoning, visual in-flight navigation and position fixing, radio navigation systems (ADF, VOR, DME, ILS, radar, GNSS and performance-based navigation), area navigation and flight management systems, and advanced topics such as great-circle and rhumb-line planning and polar or oceanic navigation. The ATPL Navigation study guide has 8 sections and about 2,968 words.
01Basics of Navigation: The Earth, Coordinates, Direction and Distance
Questions in this domain test whether you can move confidently between the idealised Earth and the numbers used operationally. The Earth is approximated by an oblate spheroid (ellipsoid): polar radius about 6357 km, equatorial radius about 6378 km, flattening about 1/298.3.
415 words, about 2 min02Magnetism and Compasses: Terrestrial Field, Variation, Deviation and Compass Systems
The Earth behaves like a tilted dipole. The magnetic poles drift and do not coincide with the geographic poles.
411 words, about 2 min03Charts: Projections and Practical Use of Aeronautical Charts
A chart is a projection of a curved surface onto a plane; every projection distorts something. You must know which properties are preserved and which are not.
410 words, about 2 min04Dead Reckoning: Triangle of Velocities, Drift and Ground Speed
Dead reckoning combines heading, true airspeed, wind velocity and time to predict position. The triangle of velocities has three vectors: true heading/true airspeed (the aircraft through the air), wind velocity (direction from which the wind blows, at the altitude flown), and the resultant true track/ground speed.
373 words, about 2 min05In-Flight Navigation: Visual Navigation, Position Fixing and Lost Procedures
Visual navigation uses ground features, timing and heading to confirm position. Good practice: identify large, unambiguous features (coastlines, large lakes, motorway junctions, airfields), compare them with the chart, and use the "clock code" and the 10° cone from the nose to judge relative position.
361 words, about 2 min06Radio Navigation: ADF, VOR, DME, ILS, Radar and GNSS
Radio waves travel at about 300,000 km/s; frequency × wavelength = speed of light. Lower frequencies (NDB, ADF) follow the surface and are less line-of-sight limited but more affected by static and night effect; VHF and above are essentially line-of-sight, so range depends on altitude.
319 words, about 2 min07Area Navigation and Flight Management: RNAV, FMS and Databases
Area navigation allows flight on any desired path rather than directly to or from ground stations. RNAV systems compute position from multiple sensors (VOR/DME, DME/DME, GNSS, inertial) and guide along defined waypoints and legs.
353 words, about 2 min08Adverse Conditions and Advanced Navigation: Polar, Oceanic, Great-Circle and Rhumb-Line Planning
Polar navigation relies on gyros, GNSS and inertial systems because magnetic compasses are unreliable near the magnetic poles (steep dip, weak horizontal intensity). Grid navigation uses a grid overlay on polar charts so headings are referenced to grid north rather than true north.
326 words, about 2 min