S-TEC ST360, Руководство по эксплуатации для пилотов

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7
ALTITUDE SELECTOR/ALERTER
Theory of Operation
The Altitude Selector/Alerter (ASA) enables the pilot to preselect al-
titudes and rates of climb or descent to be used by the autopilot. The
ASA reads and decodes the altitude information from the altitude en-
coder. This decoded information is adjusted by the setting of the baro-
metric (baro) calibration and then compared to a selected altitude setting.
When the information from the selected altitude matches the decoded
altitude information from the encoder, the altitude selector computer sig-
nals the autopilot to electrically engage the altitude hold mode of the
autopilot.
The Vertical Speed (VS) Selector provides an electrical output to the
autopilot pitch flight guidance computer that is proportional to the ampli-
tude and polarity (direction) of the vertical speed. For example, a + 500
feet per minute (FPM) climb VS, would produce a plus (+) voltage in an
amount representing 500 FPM. This signal is not utilized by the autopi-
lot until the VS Mode is engaged. At that time, the autopilot compares
the existing vertical speed with the selected vertical speed and maneuvers
the airplane to match these signals. The vertical speed selector portion of
the ASA can be disabled by pushing the “MAN” (Manual) switch which
will cause the autopilot to revert to its normal vertical speed command
system.
The Vertical Speed Selector portion of the ASA will function any
time the selector is showing a Vertical Speed and the Vertical Speed Mode
of the autopilot is selected. However, the Altitude Selector will function
only when the transponder and encoder are operating and when both the
VS and ALT Modes of the autopilot are selected.