Btw / Nxt, Bearing And Angle Deviation Relative Next Course - Nexus Wind Data Installation And Operation Manual

4: OPERATION
3.6.5

BTW / NXT, Bearing and angle deviation relative next course

To get this function, set NAV = On C14 (See 5.1.4).
This function is using both the Compass and the navigator information to
calculate the angle deviation between the bearing and the course after
tack. i.e. the angle deviation is exactly what you should expect after the
tack.
[BTW] is showing the actual Bering to Waypoint and [NXT] is showing
the negative [-], positive tack or downWind angle that you would expect if
you where tacking or jibing.
You may use COG but our recommendation is to use the Compass since
the response and accuracy is superior. If you use COG without a
differential GPS you will loose too much accuracy in the information.
[BTW] and [NXT] is toggling.
TACK :
Example: If you expect your drift to be 05 , your tack should be made
when you read [NXT 05 ] to be on (and stay on) lay line.
While you are approaching the proper angle, the value is negative, i.e. -
12° and then increasing to 00° which is on lay line after tack except for
the drift which is the margin you must add to compensate for the drift.
Note! This function is only used on the last leg.
WIND
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