Simrad ROBERTSON AP45 manual XTE mode

Page 2-6	Robertson AP45 Autopilot
	Operation
	GPS satellite
00° ON TRACK	04° XTE=R0.01NM
NAVIGATION	NAVIGATION

INFO DISPLAY INFO DISPLAY

XTE

WAYPOINT 1

Heading=100°

WAYPOINT 2

WAYPOINT 3

New heading = 70°

RESET

ALARM

ACCEPT CHANGE?	RESET	10MIN CHG 30°
Y: RESET N: AUTO		NAVIGATION

INFO DISPLAY INFO DISPLAY

	COURSE DISPLAY
	Note!
	Steering through a route of waypoints with the AP45 allows you the total flexibility
	for automatic waypoint sequencing, but combines the safety feature of requiring
	operator acknowledge for course changes in excess of 10 degrees.
	If the AP45 is connected to a Nav. receiver that does not transmit a message with
	bearing to next waypoint, it will pick a XTE message and steer on Cross Track
	Error only. In that case you have to revert to AUTO mode at each waypoint and
	manually change set course to equal bearing to next waypoint and then select NAV
	mode again.
XTE mode	When the AP45 steers using cross track error only, it corrects the set course in
	order to keep the vessel on a straight track between two waypoints. Bearing
	change at waypoints must be made manually by temporarily go to Auto mode -
	change set course - and revert to Nav. mode.
	Use the following procedure for XTE steering:
	1. Enter the desired bearing line(s) to the Nav. receiver using the present position
	and the first waypoint or destination. Distance between waypoints should be of
	minimum 2-3 n.m. Otherwise there may not be sufficient time for the system to
	calculate the XTE, and for the autopilot to alter the course and bring the vessel
	onto the bearing line again.
	2. Read the calculated bearing to waypoint from the Nav.receiver.
	3. Select AUTO-mode on the AP45, and set the course to the waypoint showed on
	the navigation receiver.
	Before going to step 4, ensure that the XTE is within +/- 0.1 n.m. to avoid
	hazardous course change when selecting NAV-mode.
	4. Select NAV-mode on the AP45. The autopilot now automatically changes the
	set course to reduce the Cross Track Error (XTE) to zero. The information
	display shows the number of degrees the autopilot has changed the set course,
	and the XTE in 1/100's of a nautical mile. Note that the display readout will be
	delayed, depending upon the NAV. FILTER setting.

Simrad Robertson AS

Egersund - Norway