ATPL General Navigation (Gnav, subject 061) is the foundation subject that teaches you to work out where you are, where you're going, and how long it'll take to get there — using nothing more than a chart, a navigation computer and a stopwatch. It's the subject that turns "point and hope" into the precise, repeatable pilot navigation that underpins every flight you'll ever make. Most students find Gnav the most calculation-heavy of the 13 ATPL subjects, but also the most rewarding once it clicks — because every other subject from Radio Navigation to Flight Planning leans on the same core principles.
The EASA and UK CAA General Navigation syllabus covers seven main areas. Below is what each one includes and why it matters.
1. The Earth, Coordinates and Time
The shape of the Earth, latitude and longitude, great circles and rhumb lines, convergency and conversion angle, departure, and the relationship between distance on the Earth and the chart you're flying with. Time is taught here too — UTC, Local Mean Time, time zones, the date line, and sunrise/sunset calculations. This is the language the rest of the subject is written in.
2. Direction and Magnetism
The Earth's magnetic field, magnetic variation and isogonals, deviation in the aircraft, and the difference between true, magnetic and compass headings. You'll learn how the direct-reading magnetic compass works, why it lies during turns and accelerations (and which way), and how to correct for it. This is the bedrock of every heading calculation you'll do for the rest of the syllabus.
3. Charts and Projections
Mercator, Lambert Conformal Conic and Polar Stereographic projections — how each one represents the Earth on a flat surface, where its scale is true, where it distorts, and which is right for which flight. Chart scale, conformality, equidistance, reading plotting symbols and measuring tracks and distances. By the end of this section a 1:1,000,000 chart should feel as readable as a page of text.
4. Dead Reckoning Navigation
The triangle of velocities — combining true airspeed, heading, wind speed and wind direction to work out track and groundspeed. The CRP-5 (or E6B) navigation computer, mental dead reckoning, time-distance-speed calculations, and the 1-in-60 rule for correcting off-track errors. Every IFR pilot still uses these techniques today, and the exam tests them constantly.
5. In-Flight Navigation and Position Fixing
Using DR, visual references and basic radio fixes to keep track of your position; revising estimated times of arrival mid-flight as winds and groundspeed change; identifying when you've drifted and how to get back on track without burning extra fuel. This is where the theory becomes airmanship.
6. Inertial Navigation Systems (INS and IRS)
How a self-contained inertial system measures motion using accelerometers and gyroscopes, the difference between gimballed INS and modern strapdown IRS, Schuler tuning, Coriolis correction, alignment procedures and drift errors. You don't need to be able to repair one — you need to know what it's telling you and why it's sometimes wrong.
7. The Navigation Computer (CRP-5 / E6B)
The CRP-5 slide-rule computer is a separate examined skill in itself. You'll learn to use it for wind triangles, time-distance-speed, fuel calculations, temperature corrections, density altitude, mach number and unit conversions. Speed and accuracy on the CRP-5 is what separates students who finish the Gnav exam with time to spare from students who run out of time on question 30.
All of this is covered in depth in the evoATPL General Navigation Study Book (printed or digital eBook), with hundreds of worked examples and exam-style practice questions inside the evoATPL Question Bank. If a specific topic — Mercator scale, triangle of velocities, INS drift — isn't clicking, a couple of focused 1-to-1 hours of online instructor-led revision is usually all it takes to break through.
