S-TEC 01279, Руководство по эксплуатации для пилотов

Страница: 15 / 24

15
Decision Height (DH) Alert Mode
The Decision Height (DH) Alert Mode will provide altitude alerting
at the set DH altitude by activation of the chime and flashing of the DH
annunciator. The chime will sound entering and leaving a 100 ft. win-
dow at the DH.
To set, push DTA for entry, select DH Mode. The display will ini-
tially show 0.0. Rotate the selector knob to obtain the desired DH to the
nearest 100 ft. above the specified decision height. For instance, for a
DH of 1160 ft., set in 1.2 (x1000) for 1200 ft. After setting the desired
DH, push DTA to enter the selected DH. The display will show the se-
lected DH for approximately 5 seconds and will then revert to altitude
mode and display the altitude until the DH is reached in the descent. At
the set DH window, the DH alert will activate. In our example, the alert
will sound/flash at 1250 ft. and again at 1150 ft., alerting the pilot that he
is at or near the set decision height.
The DH Mode can be disabled by pushing the DH switch causing the
DH annunciator to extinguish, leaving the altitude displayed.
It is necessary to select DTA and ENT mode to display or enter the
DH value or change a DH value, once you have returned to operate mode
(ENT Extinguished). Repeated activation of the DH button in operate
mode will alternately enable or disable the DH mode, without changing
the display.
CAUTION
Due to possible inaccuracies that may exist in using the Altitude
Selector/Alerter, the DH Mode should not be used as sole means of
determining missed approach altitude.