Technical data

Product Specification
HIF-2121/R5 CAGE CODE: 97896 SCALE: NONE SIZE: A DWG NO: 965-1176-601 REV: D SHEET 25
MKVI/MKVIII EGPWC supplies a discrete pop-up signal. This can be used to switch flight deck displays between the
Weather Radar and the terrain display. In addition, the MKVIII EGPWC can be display terrain on an Electronic Flight
Instrument System (EFIS) display.
Terrain is depicted on a display as shown in Figure 1.3.2-5.
YELLOW CAUTION AREA
"CAUTION TERRAIN,
CAUTION TERRAIN"
RED WARNING AREA
"TERRAIN TERRAIN, PULL UP!"
BACKGROUND TERRAIN
FIGURE 1.3.2-5: TERRAIN AWARENESS DISPLAY ON EFIS NAVIGATION DISPLAY (SIMULATED)
Areas of terrain that satisfy the terrain caution alert criteria are shown in solid yellow, and areas of terrain that satisfy the
terrain warning alert criteria are shown in solid red. Terrain which is significantly close to the aircraft, but which satisfies
neither the caution or warning criteria, is shown as a green, yellow or red dot pattern whose perceived brightness is less than
the yellow caution or red warning area. The density of the pattern is coarsely varied to depict terrain altitude with respect to
the aircraft.
Reference section 6.7.4 for a detailed description of the display presentation.
1.3.2.3 Obstacle Alerting
The EGPWS has the capability to detect and annunciate obstacle alerts for obstacles contained in the EGPWS obstacles
database. The same visual annunciations that are activated for terrain caution/warning alerts are activated for obstacle
caution/warning alerts. The actual alert voices for obstacles are controlled via the selected audio menu. The obstacle voice is
similar to the terrain alert, except that for an obstacle alert, the word “Obstacle” replaces the word “terrain”. Obstacle alerting
is activated by a configuration item in the configuration module.