Let me walk you through what you're seeing — Page 655, Lesson 760

This is the index of the book — the alphabetical listing of every topic covered in the entire Instrumentation volume. So what I want you to take away from this is not the individual entries themselves, but the structure of the whole syllabus you're about to work through. Let me walk you through what you're seeing. The index is organized alphabetically, from A to Z, and each entry gives you the page number where that topic is discussed in the main body of the book. So if you're looking for a specific subject, you flip to the back, find the term, and it tells you exactly where to go. Now, let me point out some of the key systems and concepts you'll be meeting, because this index is essentially a map of the entire course. First, you'll notice the Control and Display Unit, abbreviated CDU. This appears several times in the index — pages 40, 240, 271, and 276. The CDU is the pilot's interface with the flight management computer. It's the screen and keypad you use to enter flight plans, performance data, and route information. You'll see it referred to in different contexts throughout the book, which is why it appears multiple times. Related to that, you have the Control Panel on pages 281 and 283, and the Control Unit on page 308. These are the physical switches, knobs, and buttons you use to operate various aircraft systems. The distinction between a "panel" and a "unit" matters — a panel is typically a grouping of controls, while a unit is a self-contained piece of equipment. You'll also see Control Loops on page 353. This is a fundamental concept in automatic flight control. A control loop is the closed cycle where a system senses its output, compares it to a desired value, and corrects any difference. Think of it as the brain of an autopilot — it continuously monitors and adjusts. Now, look at Control Wheel Steering, abbreviated CWS, on page 372. This is a specific autopilot mode where the pilot physically moves the control wheel, and the autopilot follows the pilot's input. The pilot is essentially telling the autopilot "hold this attitude" by moving the controls, and the autopilot then maintains that attitude. You'll see Coriolis on page 236. This is a physics term — the apparent deflection of a moving object due to the Earth's rotation. In navigation instruments, particularly gyroscopes, the Coriolis effect causes errors that we have to account for. It's a subtle but important concept. Moving on, you have Cost Index on pages 274 and 275. This is a number the flight crew enters into the flight management system that tells it whether to prioritize speed or fuel economy. A low cost index means save fuel, a high cost index means save time. It's a trade-off calculation the computer makes continuously. You'll see Course Deviation Indicator, abbreviated CDI Bar, on page 340. This is the needle or bar on your navigation display that shows whether you're left or right of your intended course. When the bar is centered, you're on course. When it deflects, you're off. Now, some acronyms you'll need to know. CPA on page 483 — that's Closest Point of Approach, used in collision avoidance. CPDLC on pages 325, 326, and 327 — that's Controller-Pilot Data Link Communications, which is text messaging between the pilot and air traffic control instead of voice. CPU on page 308 — Central Processing Unit, the computer chip that does the actual processing. You'll see CRT on pages 281 and 282 — that's Cathode Ray Tube, the older type of display screen used before modern LCDs. CVR on page 505 — Cockpit Voice Recorder, the device that records all cockpit audio for accident investigation. Look at Cross Track Error on page 243. This is the distance you are off your intended flight path, measured perpendicular to the track. It's a key navigation concept — the CDI bar I mentioned earlier is showing you this error visually. Cross-coupling on page 17 — this refers to when one axis of control affects another. For example, when you roll an aircraft, it tends to yaw, and vice versa. This is a real aerodynamic phenomenon we have to manage. You'll see Data Base on page 272 — this is the navigation database stored in the flight management computer, containing waypoints, airways, airports, and procedures. Data Link on page 318 — this is the general term for digital communication between the aircraft and ground stations. Data Communications Display Unit on page 318 — the screen that shows these data link messages. Data Management Unit on page 499 — a computer that manages data flow between systems. And Data Digital Buses on page 17 — these are the digital highways that carry data between different aircraft systems. Now, some specific items. Damping liquid and Damping wires, both on page 121 — these are components of certain mechanical instruments. Damping is the process of reducing oscillation. In a compass or gyroscope, damping liquid or wires slow down the movement so the needle doesn't swing wildly — it settles smoothly on the correct reading. Configuration Module on page 97 — this is a device that stores the specific configuration data for an aircraft, like its weight and balance limits. Configuration Warning on page 446 — this is an alert that sounds when the aircraft is in an unsafe configuration, like trying to take off with flaps not set correctly. Continuous BITE on page 100 — BITE stands for Built-In Test Equipment. Continuous BITE means the system is constantly monitoring itself for faults, not just during a specific test. It's always watching. Cone of Confusion on page 369 — this is a navigation concept. When you fly directly over a VOR station, the signals become unreliable in a cone-shaped area directly above the transmitter. The instruments may fluctuate or give false readings in this zone. Correction of Coefficients on page 204 — this relates to compass errors. A compass has certain systematic errors, called coefficients, that can be corrected by adjusting magnets or soft iron compensators. This is the mathematical process of correcting those errors. Correction of TAT/RAT to SAT on page 32 — TAT is Total Air Temperature, RAT is Ram Air Temperature, and SAT is Static Air Temperature. When an aircraft moves through the air, friction and compression heat the air, so the temperature you measure is higher than the actual outside air temperature. This correction process converts the measured temperature back to the true static temperature. Corrective Advisories on page 484 — these are warnings that not only tell you something is wrong, but also suggest what to do about it. They're corrective, not just informative. Course Selection (Localizer) on page 291 — this is how you set the desired course on the localizer, which is the lateral guidance component of an ILS approach. Cruise Control Manual on page 273 — this is the manual mode of the autothrottle system, where the pilot sets a specific speed or thrust and the system maintains it. Cruise Lateral Navigation (LNAV) on page 275 — LNAV is the autopilot mode that controls the aircraft laterally, keeping it on the programmed route during cruise. Current Heading on page 291 — this is the direction the aircraft's nose is pointing right now. Current Track on page 291 — this is the actual path the aircraft is making over the ground. These are different — heading is where the nose points, track is where you're actually going, accounting for wind. So, what you have here is the complete map of your course. Every one of these terms — from the CDU to the CVR, from Coriolis to Cross Track Error — is a topic we'll be covering in depth. This index is your reference tool. When you're studying and you need to find something quickly, this is where you look. The key takeaway is the breadth of what you're about to learn. You're covering navigation instruments, flight management systems, autopilot controls, data communications, warning systems, and the physics behind all of it. This is the full scope of aircraft instrumentation at the ATPL level.