NORTHROP GRUMMAN NAVITWIN IV, Руководство по эксплуатации, установке и обслуживанию

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056360/E NAVITWIN IV
3-2 Sequence of Events and Actions
3.3 Sequence of Events and Actions
Once the GAS mode has been triggered, a definite sequence of events
takes place, requiring specific actions on the part of the operator to
return the system into a regular operating mode, as outlined below.
1.
Initial situation:
All systems are operating normally.
In the example given below, Gyro 1 is active and Gyro 2 is inactive,
the sequence of events and actions applies as well reciprocally with
Gyro 2 active and Gyro 1 inactive.
– A gyro / other (true) heading source is
active as Gyro 1.
– A second gyro / other (true) heading
source is available, inactive as Gyro 2.
– GAS is enabled and the heading differ-
ence between the active and the second-
ary source, is smaller than the set max.
diff. GAS threshold in the service setup.
2. Event: The active heading source Gyro 1 fails (loss of heading data).
NAVITWIN IV immediately takes over the management of the com-
pass system. Failure of active source triggers immediate GAS head-
ing substitution at the NAVITWIN IV‘s GAS serial data output.
– NAVITWIN IV raises a
„Failure Gyro 1“ alarm
(FAILURE GYRO 1) and a
„GAS Changeover Gyro 2“ alarm
(CHANGEOVER GYRO) appears in the
alarm window.
– Multiple alarms may occur if data other
than heading is also lost (e.g. rate of
turn, speed, position) and will than
increase the indicated number of alarms.
– Dashes appear in the heading display of
Gyro 1.
– The NAVITWIN IV automatically selects
the second heading source as the active
source, indicated by a pair of arrow sym-
bols being shown next to the source’s
name.
– A „Failure Gyro 1”(FAILURE GYRO 1)
alarm message appears in the alarm
window.
With all external devices connected to NAVITWIN IV outputs other
than the dedicated GAS serial data output, the switch over unit
abruptly switches over to the heading source 2 and new heading
data are immediately transmitted to the external devices without any
alignment of heading.
Devices connected to the heading sources via the Switch-Over Unit
will also receive immediately heading data of the heading source 2.
DISPLAY DATA
MONITOR
ALARM
NO ACTIVE
ALARM
Hdg. Diff
10°
Gyro 1
Gyro 2
GYRO
1
GYRO
2
MAGN
COMP
246.8
247.7
247.0
12.8 kn
AUTO
SPEED
DISPLAY DATA
MONITOR
ALARM (1/2)
FAILURE
GYRO 1
Hdg. Diff
10°
Gyro 1
Gyro 2
GYRO
1
GYRO
2
MAGN
COMP
- - - . -
247.7
247.0
12.8 kn
AUTO
SPEED