Technical data

Product Specification
HIF-2121/R5 CAGE CODE: 97896 SCALE: NONE SIZE: A DWG NO: 965-1176-601 REV: D SHEET 11
1.3.1.1 Mode 1 - Excessive Descent Rate
Mode 1 provides alerts when the aircraft has excessive descent rate close to the terrain (see Figure 1.3.1.1-1 and 1.3.1.1-2).
Figure 1.3.1.1-1 shows the turboprop curves, available on MKVI and MKVIII EGPWS. Figure 1.3.1.1-2 shows the turbofan
curves, available on MKVIII EGPWS only and selectable at the time of installation.
"PULL UP!"
"
S
I
N
K
R
A
TE
"
RADIO ALTITUDE (FEET)
0
500
1000
1500
2000
2500
0
2000
4000 6000
8000
DESCENT RATE (FEET/MINUTE)
"SINKRATE"
"PULL UP!"
FIGURE 1.3.1.1-1: MODE 1 - EXCESSIVE DESCENT RATE (TURBOPROP)
"PULL UP!"
"
SI
NKRA
TE"
RADIO ALTITUDE (FEET)
0
500
1000
1500
2000
2500
0
2000
4000 6000
8000
DESCENT RATE (FEET/MINUTE)
"SINKRATE"
"PULL UP!"
FIGURE 1.3.1.1-2: MODE 1 - EXCESSIVE DESCENT RATE (TURBOFAN)
If the aircraft penetrates the “outer” alert boundary, the aural message “Sinkrate” is generated, and alert discretes are output
by the computer for driving visual annunciators. If the aircraft penetrates the “inner” alert boundary, the aural message “Pull
Up!” is generated and visual alert discretes are also output. The alert boundaries are defined in terms of aircraft vertical
speed (barometric altitude rate) and radio altitude.