Topographical Maps and Map Reading — Page 229, Lesson 207

I want to walk you through the start of the chapter on topographical maps and map reading. This is a fresh topic, so let's begin with the core skill itself. Map reading is defined as visualizing the physical features of the ground as they are represented on the map by symbols. The goal is to form a mental picture of the ground by relating those features one to another. This specific process is called reading map-to-ground. It is the basic technique you use when you are confident that you are near your intended track and near your planned time. There is a reverse process used when you are less certain of your position, called reading ground-to-map. That involves seeing an arrangement of features on the ground, then finding those same features on the map, and thereby locating yourself. Visual navigation using map reading is a skill that needs practice and develops with experience. Several factors make the task easier, and the most important of those factors are thorough flight planning and preflight route study. In flight, it is also important to try to remain on track and on time, and if you do go off track, to regain track as soon as possible. But you must not concentrate too much on navigation alone. It is equally important to keep a good look-out to reduce collision risks, to be aware of any potential weather problems, and to manage the aircraft systems. Now let's move to visual checkpoints. During the planning stage, the pilot studies the route and selects visual checkpoints, normally occurring at about 5 to 10 minute intervals. A visual checkpoint is a significant ground feature that can be overflown or used as a reference to fly an appropriate distance away from. Ideally, the checkpoint should be recognizable from some distance away to allow for timely alterations of heading. Importantly, visual checkpoints do not need to be exactly on track — a good feature close to track is better than a poor feature on track.