OFF-COURSE ALARM
When the autopilot is set to either ‘Auto’ or ‘Vane’
mode a built in off-course alarm is automatically
set up. The off-course alarm will sound from all
control units when the vessel deviates for any
reason from the original course by more than 15
degrees for over 10 seconds. If an auxiliary alarm
is fitted this will also be sounded after a one
minute delay to allow the watchkeeper to take
corrective action.
The alarm will be silenced if the vessel returns
to within 15 degrees of the original course. If the
vessel does not return within course limits the
alarm can only be silenced by disengaging the
autopilot and resetting a new course. This facility
is particularly useful for sailing craft when in ‘Vane’
mode since an automatic warning will be given of
significant wind direction changes.
3.2.6 RADIO NAVIGATION INTERFACE
The operating handbook for the Loran ‘C’ or
Radio Navigation Interface system is
supplied with the interface unit. The interface unit
connects to the control unit serial bus and
supervises the autopilot in ‘Auto’ mode to follow a
computed track. When the Radio Navigation
Interface system is switched on to supervise the
autopilot the course display is replaced by an
indication of cross track error preceded by the
mode indication
as shown in Section
3.2.4.
