Furuno FEA-2107-BB - How to Stop or Modify Already Enabled Route Turn; Notes

29. Steering With YOKOGAWA Autopilot PT-500A
29-9
29.4.8 How to stop or modify already enabled route turn
There are two cases that the automatic route turn must be stopped or modified.
• The turn cannot be performed up to the final value.
• The turn goes outside of the planned turn. (Too fast or too slow).
Stop a turn
To stop a turn, change the steering mode from "NAVI" to "AUTO" on the YOKOGAWA steering control unit.
Modify turn
What do you want to do How to do
Use value different from
set course
The problem is that radius control is only available in the steering mode NAVI. As
soon as you change the steering mode to something else, your ship stops following the
radius. Below is what you can do.
Change from "NAVI" to "AUTO". This stops turning completely as the current gyro
heading is selected as the new set course for the Autopilot. Then, set a new final value
for set course and select a suitable max. rudder angle to prevent too fast turning.
Set the steering wheel to a suitable angle to continue approximate radius (i.e. equal
rudder angle than before). Then change from "NAVI" to "HAND". Continue manual
steering.
Change from "NAVI" to "NFU". Then, use the NFU steering lever. Continue manual
steering.
Compensate too fast
turning
As soon as you change the steering mode to something other than "NAVI," your ship
stops following the radius. Below is what you can do.
Change from "NAVI" to "AUTO". This stops the turning completely as the current
gyro heading is selected as the new set course for the autopilot. Then set a final value
of set course and select a suitable max. rudder angle to prevent too fast turning.
Set the steering wheel to a suitable angle to continue approximately larger radius (i.e.
smaller rudder angle than before). Then, change from "NAVI" to "HAND". Continue
manual steering.
Change from "NAVI" to "NFU". Continue manual steering.
Compensate too slow
turning
As soon as you change steering mode to something other than "NAVI" your ship stop
following radius. Below is what you can do
Set the steering wheel to a suitable angle to continue approximate smaller radius (i.e.
higher rudder angle than before). Then, change from "NAVI" to "HAND". Continue
manual steering.
Change from "NAVI" to "NFU". Continue manual steering.
29.4.9 Notes
Accuracy of route steering
Accurate route steering is defined as a small cross track error when automatically following the route. Two of the
Route Parameters - Drift compensation and Gyro error compensation - have a significant effect on the accuracy of
route steering. If you need more accurate route steering, then both of these parameters should be enabled. Before
activating the Gyro error compensation, see the section on Gyro error correction to understand the possible
methods for gyro error compensation.