EFIS is the modern glass-cockpit replacement for the old mechanical flight… — Page 287, Lesson 285

This is the start of Chapter 17, the Electronic Flight Information System — EFIS. So let's set the stage properly, because this is a big one for your instrument flying. EFIS is the modern glass-cockpit replacement for the old mechanical flight instruments. Instead of separate spinning gyros and needles, you get a single integrated electronic display. The heart of what we're looking at in this chapter is the EHSI — the Electronic Horizontal Situation Indicator. That's the display that shows you your navigation picture: where you are, where you're going, and how you're tracking relative to your nav aids. Now, the chapter is laid out in a very deliberate order, and I want you to see the structure before we dive into the details. It opens with an introduction, then moves to the EHSI Controller — that's the panel unit you use to select what the display shows. From there we go through the Display Modes, and this is the meat of it. There are six modes: Expanded VOR, Full Rose VOR, Expanded ILS, Full Rose ILS, Map, and Plan. Each one is a different way of presenting the same navigation data, and you need to know when and why you'd select each. After the modes, we get into EHSI Colour Coding — the standard colours used across the display so you can read it at a glance — and then EHSI Symbology, which is the meaning of every symbol and icon you'll see on screen. The chapter finishes with practice questions, an appendix, and the answers. So the key takeaway right now: EFIS is the system, EHSI is the display, and the controller is how you command it. The modes are your view options, and the colour and symbology standards are the language the display speaks. We'll work through each of those in turn.