Now the satellite navigation family — Page 657, Lesson 772

This is the index of your ATPL Instrumentation manual — the G through H section. I want to walk you through what's here, because the index itself is a map of the systems you'll be tested on. Let's start with the navigation and landing aids. Glide Slope Deviation appears on page 291 — that's the vertical guidance in an ILS approach, telling you whether you're above or below the correct descent path. Go-around is on page 16, and Go-around Mode on page 395 — that's the autopilot or autothrottle configuration that commands a missed approach, typically full power and a pitch-up attitude. Now the satellite navigation family. GNSS — Global Navigation Satellite System — is on page 325. That's the umbrella term for all satellite constellations. GPS — the American Global Positioning System — is on page 271. These are the systems that give you position anywhere on the globe. Global Communications on page 317 and Global Air Traffic Management System on page 319 — these are the worldwide data-link and ATM infrastructure that let aircraft communicate and be managed across oceans and continents. Now the warning systems. GPWS — Ground Proximity Warning System — appears on pages 263, 266, 311, and 449. That's the system that warns you if the aircraft is in dangerous proximity to terrain. Note the index also lists the full name Ground Proximity Warning System (GPWS) on pages 263, 266, 311, and 447 — so the acronym and the full name point to slightly different page ranges, but it's the same system. Let's move to the gyroscopic instruments, which are a big block here. Gyroscopes on page 137 — the spinning-wheel devices that provide attitude and heading reference. Gyroscopic Inertia on page 138 — that's the property of a spinning mass that resists changes to its axis. Gyro Horizon on page 178 — the attitude indicator. Gyro-magnetic Compass on page 211 — a compass that combines a gyroscope with magnetic sensing. Gyro Compassing on page 237 and Gyro Compassed on page 240 — these relate to the technique of using the gyro to determine or correct heading. Gyro Stabilized Platform INS on page 256 — that's the inertial navigation system built on a gyro-stabilised platform. Now the magnetic compass theory. Hard Iron on page 109 and Hard Iron Magnetism on page 202 — this is the permanent magnetism in the aircraft's structure that causes compass deviation. Gravity on page 257 and Gravity Effects on page 232 — these relate to how gravity influences the sensing elements in gyroscopic and inertial systems. Let's look at the heading instruments. Heading Indicator on pages 211 and 218 — the directional gyro. Heading "bug" on page 291 — that's the movable marker you set on the instrument to mark a desired heading. Heading Select on page 368 and Heading Select Marker on page 219 — the control and the display marker for selecting a heading on the flight director or autopilot. Heading Mode on page 345 — the autopilot mode that holds the selected heading. Heading & Drift on page 243 — that's the navigation display showing heading and drift angle. Heading Selector Control — that's the knob you turn to set the desired heading. Finally, Hardware on page 308 — that's the physical computing and electronic components of the systems. Now, I want to point out something important about this index. You'll notice Green Arc on page 45 — that's the green arc on an engine or flight instrument indicating the normal operating range. And note the Heading Selector Control entry is cut off at the end of this excerpt — it continues on the next page of the index. So here's the structure I want you to take away. This index groups the material into four families: navigation and landing aids (Glide Slope, GNSS, GPS), warning systems (GPWS), gyroscopic and inertial instruments (Gyroscopes, Gyro Horizon, Gyro-magnetic Compass, Gyro Stabilized Platform INS), and heading control (Heading Indicator, Heading Select, Heading Mode). The magnetic compass theory — Hard Iron, Gravity — feeds into how those gyro and compass systems behave. When you study this book, you'll find that the gyroscopic instruments on pages 137 through 256 build on each other — the basic gyroscope physics leads to the attitude and heading instruments, which then lead to the inertial navigation platform. And the heading control systems on pages 291 through 368 are the autopilot and flight director functions that use those instruments. That's the G and H section of your index. You now have the full map of where each system lives in the manual.