We're starting a brand-new topic now: the index of the Radio Navigation manual — Page 389, Lesson 384

We're starting a brand-new topic now: the index of the Radio Navigation manual. I want to walk you through what this index is telling us, because it's a map of the entire syllabus we're about to cover. First, you'll see the "1:60 rule" listed on page 162. This is a fundamental mental-math tool we use in navigation — it relates an off-track error to a distance and a track angle. We'll get to it in due course. Then we have the RNAV family. "2D RNAV" appears on pages 262, 263, and 264. "3D RNAV" is on page 262. And "4D RNAV" is on pages 262 and 267. These are the different dimensions of area navigation — 2D is lateral and vertical, 3D adds a vertical profile, and 4D adds time. We'll unpack each one when we reach those pages. You'll also see "4D Fix" on page 316 — that's a specific point defined in four dimensions, including time. Now, some very specific numbers that will come up. "15 000 Pulse Pairs" on page 249, "27 pps" on page 249, "60 pps" on page 249, and "150 Pulse Pairs Per Second" on page 249. These are all pulse rates — the rate at which a transmitter sends out pairs of pulses. Different systems use different rates, and you'll need to know which is which. We also have "16 700 000" on page 234 — that's a frequency in Hertz, 16.7 MHz, which is a specific aviation communication frequency. And "24 Bit Code" on page 234 — that's a digital code used in some transponder or data-link systems. Then we have the emergency codes: "4096" on page 233, "7500" on page 233, "7600" on page 233, and "7700" on page 233. These are the transponder codes — 7500 is hijack, 7600 is radio failure, 7700 is emergency. 4096 is the total number of possible codes in the standard transponder system. Moving to the "A" section. "A9W" on page 115 — that's a specific signal or system designation we'll encounter. "ABAS" on page 319 — that's Aircraft-Based Augmentation System, a GPS integrity system. "Absorption" on page 19 — that's how the atmosphere attenuates radio signals. "Accuracy of ADF" on page 101 — ADF is Automatic Direction Finder, and we'll study its accuracy limits. "Achievable Ranges" on page 31 — the maximum distances we can expect from various aids. "ACT ECON PATH DES" on page 277 — that's a flight management system command, "Activate Economic Path Descent." "ADC" on page 261 — that's Air Data Computer. "ADF" on pages 85 and 285 — the Automatic Direction Finder again. "Aerial Feeders" on page 56 — the cables that carry RF energy from the transmitter to the antenna. "Aerodrome Surveillance Approach Radars" on page 201, and "Aerodrome Surveillance Radar" on page 199 — these are the ground radars used for approach control. "Aeronautical Stations" on page 75 — ground stations that communicate with aircraft. And "AFDS" — that's the Autopilot Flight Director System, which we'll see integrated with navigation. So this index is our roadmap. Every one of these terms — the pulse rates, the codes, the RNAV dimensions, the radar types — is a building block. We'll take them one at a time, in order, and by the end you'll have the full picture of radio navigation as a professional pilot needs it.