B&G H2000 Pilot *DISCONTINUED* - Manual (Page 98)

h2000 User Manual
98 HB-0845-06
3.4 TRUE WIND CORRECTION
Calibration of True Wind Angle and True Wind Speed will
automatically correct Apparent Wind Angle and Apparent
Wind Speed errors.
3.4.1 True Wind Direction
The need for further calibration of true wind direction will
become clear as soon as you go sailing. The true wind might
vary in direction from tack to tack, independently of any
wind shifts. This phenomenon has come to be known as the
true wind 'tacking'. We can see the direct connection
between true wind angle and direction in Figure 9 below.
True Wind
Direction
=280˚
Heading
=240˚
TWA
=40˚
Figure 10 - True Wind Direction
The reason for this is a variety of errors that enter into the
calculation of true wind angle from measured wind angle.