We're at the very front of the book — the index — Page 573, Lesson 569

We're at the very front of the book — the index. I want to walk you through what this tells you about the whole syllabus, because the index is your map of the entire General Navigation course. Look at the first entry: the 1 in 60 Rule, on page 189. That's a core navigation calculation — it lets you work out track error or closing angle using a simple ratio. You'll meet it properly later. Then under A, we have a cluster of magnetic and compass topics. Aclinic Lines on page 62 — those are lines on a chart where the angle of dip is zero, where the magnetic field is horizontal. Agonic Line on pages 47 and 62 — that's the line where variation is zero, where magnetic north and true north coincide. Angle of Dip on page 53 — the vertical angle between the Earth's magnetic field and the horizontal plane. These all hang together as the magnetism chapter. We also have Airspeed Indicator Errors on page 105, and Air Vector on page 127 — the vector representing the aircraft's motion through the air, as opposed to over the ground. Then the Earth and time topics: Angular Distance and Angular Measurements on page 9 — how we measure the Earth in degrees, minutes and seconds. Antarctic Circle and Arctic Circle on page 11 — those latitude circles at 66½° north and south. Antipodal on page 37 — points diametrically opposite on the globe. Apparent Solar Day on page 384 — the time between successive transits of the Sun. Astronomical Twilight on page 425 — the period when the Sun is between 12° and 18° below the horizon. And AWR on page 481 — that's an acronym you'll decode in the astronomy section. Under B, Balancing the Drift on page 145 — that's the technique of applying a heading correction to counteract wind drift. Under C: Calculation of True Altitude on page 115, Calibrated Airspeed (CAS) on page 88 — that's indicated airspeed corrected for instrument and position error. Cardinal Points on page 4 — north, east, south, west. Cartesian on page 7 — the rectangular coordinate system. Change of Magnetic Latitude on page 505. Chart Projections on page 283, and Chart Symbols on page 228. Then Civil Day on page 384, Civil Twilight on page 424, and the Civil Twilight Tables in the Air Almanac. So the index is telling you the shape of the course: Earth geometry, magnetism, airspeed, vectors, charts, and time and astronomy. Each entry is a topic you'll master in turn.