Btw / Nxt, Bearing And Angle Deviation Relative Next Course - Nexus NX2 Wind Data Installation And Operation Manual

WIND DATA
5.6.5 BTW / NXT, Bearing and angle deviation relative
next course
To get this function, set NAV = On C14 (See 6.1.4).
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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