Look at the entries here — Page 657, Lesson 773

This is the index of the book — the alphabetical list of every topic inside it, with the page numbers where each one appears. So what I want to walk you through is how to read this thing, because it's actually a really useful navigation tool for your studies. Look at the entries here. We've got "Heading Select Marker" on page 219, "Heading Selector Control" on page 219, "Heading Warning Flag" on page 219. These are all components of the heading indicator system — the marker is the bug you set, the selector control is the knob you turn, and the warning flag is the little indicator that tells you the instrument has failed. They're all grouped together alphabetically under "H." Then we have "Heater" on page 14, "Heating Element" on page 28, "Heating Error" on pages 29 and 30. Notice how the page numbers can be a range — "Heating Error" appears on two consecutive pages, so it's listed as "29, 30." That tells you the topic spans both pages. We've got "Hectopascal" on page 2 — that's the unit of pressure you'll use for altimeter settings. "Height" on page 53. "Helix" on page 26 — that's the spiral shape of the aneroid capsule mechanism. "High Angle of Attack" on page 415. "High Level Language" on page 310 — that's about computer programming for the flight management system. "High Speed" on page 416, "High Speed Flight" on page 83, "High Speed Micro Processors" on page 257, "High Speed Probes" on page 16 — those are the pitot probes designed for high-speed aircraft. Now here's a key one: "HOLD" on page 241, all in capital letters. That's a specific function — the hold mode on the autopilot or flight director. And "Hooke's Joint" on page 214 — that's the universal joint used in the gyro drive system. Then we get into "Horizontal" on page 120, "Horizontality" on page 120 — those are about the artificial horizon and how it maintains its reference. And "Horizontal Situation Indicator (HSI)" on page 281, with the abbreviation "HSI" also listed on page 281. Notice the pattern: the full name is listed first, then the abbreviation as its own entry pointing to the same page. That's how you cross-reference. "Hours" on page 2 — that's the time unit used in the basic measurements. "Human Engineering" on page 5 — that's the design discipline for making instruments readable and usable by pilots. Then we move into "I." "IAS" on pages 42 and 44 — that's Indicated Airspeed. "IAS/MACH Hold (SPD)" on page 370 — that's the autopilot mode that holds a selected airspeed or Mach number, abbreviated SPD. "I Bar" on page 59 — that's a specific display symbol. "Icing Conditions" on page 25. "IDENT" on pages 273 and 274 — that's the identification feature on the transponder. "Illuminated Annunciators" on page 278 — those are the lit warning indicators on the instrument panel. "ILS" on pages 286, 288, and 385 — that's the Instrument Landing System. "IMN" on page 86 — that's Indicated Mach Number. And "Inactive Waypoints" on page 293 — those are the navigation points in the flight plan that aren't currently active. So the whole point of this index is that when you're studying a specific topic, you can flip straight to the exact page. And when you see an abbreviation like HSI or IAS or ILS, you can look up the full name to understand what it stands for. This is your map to the entire book — every instrument, every system, every concept is in here, alphabetically arranged, with the page numbers you need.