As long as the wind isn't so light that you are having trouble keeping the
cruising spinnaker inflated, you should both stay on the windward side.
However, in real light air, it helps to have one or more of the crew sit on
the leeward side so the boat will heel a bit. A slight amount of heeling
will allow the weight of the spinnaker's sailcloth & sheets to help keep the
big headsail inflated & prevent it from slatting around. That way, when a
puff of air comes your way, the spinnaker will already be fully inflated &
ready to extract every possible foot-pound of kinetic energy from the wind.
A collapsed spinnaker is almost useless.
FYI, if you are sitting on the windward side & the gusts of wind are still
making you heel this much, then you should change your strategy slightly.
You should be scanning the water out to windward looking for the telltale
dark patches on the water, ripples on the water, or "cat's paws" moving
toward you. These are usually the only visible signs that a puff of wind is
coming your way. Very often, these puffs of wind will have a slightly
different direction than the average breeze. With experience, you will
learn to estimate whether the puff's wind direction will help or hinder
your progress to windward by close inspection of the pattern of ripples on
the water as it closes in on you. If the new wind direction is more on the
bow than the average wind direction, then the puff will hinder you & it is
called a "header". If the new wind direction is away from the bow, the puff
will help you & it is called a "lift". You were close reaching in the
photos. So, assuming you are trying to make optimium progress to windward:
If the puff is a header:
Just before the puff hits you, the helmsman bears off the wind (steers
slightly to leeward). If the puff isn't too strong, then the boat will
continue close reaching right thru the puff. After the puff passes by, the
helmsman, returns to the original steering bearing as the wind resumes its
average strength & direction. By making this slight course change, the
maximum possible kinetic energy is extracted from this puff of wind & the
boat maintains optimum windward progress.
If the puff is too strong to keep the boat on its feet (It's heeling too
much), then the mainsail's traveller should be let out. (i.e. Let the
traveller car slide from the midpoint on the track towards the leeward end)
At the same time, the spinnaker sheet should be let out enough to keep the
mainsail from being backwinded. After the puff has passed, the helmsman
returns the boat to its original course & the mainsail & spinnaker sheets
are trimmed in to suit.
If the puff is a lift:
Just before the puff hits you, the helmsman heads up (steers slightly to
windward). If the puff isn't too strong, then the boat will continue close
reaching right thru the puff. However, because of the course change, the
boat is making much better progress to windward than would be possible given
the average wind speed & direction (Lifts are "good" & Headers are "bad").
After the puff passes by and the boat starts to slow, the helmsman returns
to the original course. Again, by making this slight course change, the
maximum possible kinetic energy is extracted from the puff of wind.
If the puff is too strong to keep the boat upright, then you have a choice
with a lift. You can either head up & let out the traveller & spinnaker
sheet as before with a strong header. Or, you can maintain your original
course & let out the traveller & spinnaker sheets. In this second option,
when the lift hits you, the point of sail will change from a close reach to
a beam reach or perhaps even a broad reach if the wind is really flucky.
If the sails are pretrimmed for the new point of sail, the boat will
instantly accelerate. (WARNING: HIGHLY ADDICTIVE!!!) Quite often, this is
the better option in light air.
If you are just out sailing to no place in particular & want to exploit
the puff to the maximum extent on a light air day:
The fastest point of sail with a spinnaker is a broad reach. (Apparent wind
coming from behind at an angle over the transom) So, when you see the puff
coming, the helmsman should bear off or head up as appropriate for the
expected new wind direction. The sails should be trimmed for broad reaching
just before the puff reaches you . Quite often, this technique will enable
the boat to surf for several boat lengths even after the puff passes by.
It's good to have ol Mo (the boat's momentum) on your side!
The key is to always have the boat on the proper heading with the sails
pretrimmed before the puff gets to you. You want to sail in preactive,
not reactive mode.
Spinnakers are really fun aren't they?
S/V Dynamic Equilibrium
09 Sep 2002