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Moving Maps (Part One)

in Information Systems

The moving map function uses the MFD to provide a pictorial view of the present position of the aircraft, the route programmed into the FMS, the surrounding airspace, and geographical features. Moving maps offer a number of options that allow you to specify what information is presented on the MFD and how it is displayed. Moving maps typically offer several different map orientations (e.g., north up, track up), a range control that allows you to “zoom” in and out to see different volumes of airspace, and a means to adjust the amount of detail shown on the display (declutter). The moving map display does not replace looking outside the aircraft to avoid other aircraft and obstructions.


Using the Moving Map

A moving map display has a variety of uses that can aid your awareness of position and surroundings during almost any phase of flight. Verification of the displayed data with a chart accomplishes three functions:

  1. Provides you practice for retention of your map reading skills.
  2. Contributes to your readiness for continued safe navigation to a destination in the event of equipment problems.
  3. Ensures that you maintain situational awareness.

Maintaining the “Big Picture”

Moving map displays can help you verify a basic understanding of the planned route and aircraft position with respect to the route, nearby terrain, and upcoming waypoints. For example, the moving map display in Figure 5-2 shows the aircraft slightly to the left of the programmed flight route, presumably heading in the correct direction, and operating to the west of rising terrain.

Maintaining Awareness of Potential Landing Sites

The moving map in Figure 5-2 makes several nearby alternative airports visually apparent. A classic technique used by pilots to maintain awareness is to periodically ask the question, “Where would I go if I lost engine power?” The moving map can be used in this way to maintain preparedness for an emergency, if you are aware of the map scale and aircraft capabilities.

Figure 5-2. A moving map provides the “big picture.”

Figure 5-2. A moving map provides the “big picture.” [click image to enlarge]

Maintaining Awareness on the Airport Surface

On most units, you can change the range on the moving map to see a more detailed picture of the airport surface while operating on the ground. This feature is especially useful when the arrangement of runways and taxiways is complex. The moving map in Figure 5-3 shows the aircraft prepared to taxi onto one of two possible runways.

Figure 5-3. Using the moving map on the airport surface.

Figure 5-3. Using the moving map on the airport surface.

Identifying Controlled Airspace

Most moving map displays can portray surrounding airspace as well as the vertical limits of each airspace segment. This feature is particularly useful during visual flight rules (VFR) flights, but can also serve to remind you of speed restrictions that apply to airspace transitions during instrument flight rules (IFR) flight.

Identifying the Missed Approach Point

The moving map display is an especially useful aid for recognizing arrival at various points, including the missed approach point during an instrument approach. The moving map display complements the distance readout on the PFD/ MFD/FMS. Figure 5-4 shows two indications of an aircraft arriving at a missed approach point. The position of the aircraft on the moving map is very clear, and the range setting has been used to provide a more detailed view of the missed approach waypoint.

Figure 5-4. The missed approach point shown on two different displays.

Figure 5-4. The missed approach point shown on two different displays.

CAUTION: Some units can be set to change ranges automatically. In some instances, this can lead to a loss of situational awareness as you forget or miss a scale change. This can lead to sudden pilot realization at some point that the aircraft is too high, too far, or moving too fast. Manual switching (pilot selection) of the range display ensures that you are constantly aware of the distances and closure rates to points.


Catching Errors: Using the Moving Map to Detect Route Programming Errors

Moving maps are particularly useful for catching errors made while entering modifications to the programmed route during flight. Misspelled waypoints are often difficult to detect among a list of waypoints. The moving map in Figure 5-5 shows a route containing a misspelled waypoint. It is easy to detect the mistake when the information is shown pictorially. For this reason, a display such as a moving map is sometimes referred to as an error-evident display. The PFD selected track indicates incorrect settings. Always be ready and able to fly the aircraft according to any air traffic control (ATC) clearance or instructions. Disengaging all automation and then reestablishing heading, track, and altitude control is the pilot’s first priority at all times. Then, when the aircraft is on an assigned track at a safe altitude, pilot time can be expended to reprogram as necessary.

Figure 5-5. Moving maps help make route programming errors evident.

Figure 5-5. Moving maps help make route programming errors evident.

Catching Errors: Using The Moving Map To Detect Configuration Errors

Moving maps can help you discover errors made in programming the FMS/RNAV and PFD. The moving map display shown in Figure 5-6 removes the depiction of the leg to the active waypoint when the FMS/RNAV is engaged in the nonsequencing mode. This feature provides an easy way to detect the common error of forgetting to set the computer back to the sequencing mode.

Figure 5-6. A reminder that the FMS/RNAV is set in the nonsequencing mode.

Figure 5-6. A reminder that the FMS/RNAV is set in the nonsequencing mode.

The moving map shown in Figure 5-7 allows you to discover a more serious programming error quickly. In this situation, the pilot is attempting an RNAV approach. However, the course deviation indicator (CDI) has erroneously been set to display very high frequency (VHF) omnidirectional range (VOR) course indications. The CDI suggests that the aircraft is well to the west of course. The moving map display shows the true situation—the aircraft is on the RNAV approach course, but is about to depart it.

Figure 5-7. Discovering an incorrect navigation source selection using the moving map.

Figure 5-7. Discovering an incorrect navigation source selection
using the moving map.

 

 

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