14
Why a landyacht does not perform
well in rear wind? When the wind
blows from rear, whatever the sail
direction, perpendicularly or axially
oriented, the landyacht speed is
low or even zero. On one hand, if
the landyacht moves, then the
apparent wind is low, and on
another hand, the airflow is
turbulent, thus not power efficient.
If you have a look to the dogvanes,
they move randomly, especially the
extrados one, which means the
power drops or is not optimum
(picture 41). In such a situation,
change the landyacht direction in order to catch the wind from the side and release the sail sheet, these
two combined actions will allow the power to return as soon as the extrados dogvane will be back to
horizontal.
Should you have to ride downwind, I mean towards a location forcing you to move with the wind blowing
from your back, then tacking like a sail boat is more efficient, in a same way you would do if you had to
progress up-wind, but having a downwind instead of a head wind. However, you will have to bring the
landyacht by the lee each time you will have to change direction (picture 42).
If you tack downwind and your speed is too low, pay attention to the boom as it may hurt your head at
each direction change. If your speed is good, then the boom will cross slowly above your head given you
should ride faster than the wind (see hereafter supplemental theoretical information to understand why).
Picture 42: sketch illustrating a downwind ride with multiple downwind turns.
Wind
Extrados
dogvane
Dogvanes
Picture 41: view of the dogvanes when the wind blows from the rear.
Turning downwind
Wind
Turning downwind
Turning downwind
