Apparent Wind Mode; True Wind Mode - NKE GYROPILOT 3 User Manual

4.1.3. Apparent Wind mode

In apparent wind mode, the GyroPilot 3 steers the boat by following the apparent wind
angle, given by the wind speed and wind direction sensor. It is mainly used upwind. The
page displayed is identical to that of the compass, except that the steering mode label is
replaced by the apparent wind angle.

4.1.4. True Wind Mode

In true wind mode, the GyroPilot 3 steers the boat according to the true wind angle given
by the system.
Why use the True Wind mode?
The true wind mode is particularly effective when sailing downwind in heavy swell: In these
conditions, the GyroPilot 3 shows its potential. If you use the apparent wind mode
downwind and in swell, you will observe this:
As the boat descends the wave, the apparent wind speed increases, the apparent wind
-
angle decreases and therefore, the wind heads. Action of the autopilot: it makes the boat
bear away.
As the boat climbs the wave, the apparent wind speed decreases, the apparent wind
-
angle increases and therefore the wind lifts. Action of the autopilot: it makes the boat luff
up.
In swell, the apparent wind mode does not allow for perfect heading control and you have to
switch to compass mode to descend the wave with a straight trajectory.
The true wind mode allows you to go straight down the wave and keep the optimum
descending angle. The true wind angle does not vary with boat speed.
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