Saturday, September21, 2019

Spinnaker' Trim


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                         Theory of Sailing: Part 6
                                      Spinnaker Trim
                                                      By Roy Dunster & Mark Sadler
Last month's checklist for headsail trim                                                          on the windward side of the spinnaker and
included the following:                                                                           helping to control the vertical height of the
                                                                                                  pole. The `lazy sheet/guy' is the one that
                                                                                                  isn't being used at the time ­ i.e. the sheet
 Checklist                             True?                                                      on the windward side and the guy on the
 Know what effect the jib controls have S                                                         leeward side.
                                                                                                       End-For-End Gybe ­ used on boats up
 Your base upwind jib sheet setting         S                                                     to around 40 feet. In this gybe, the pole
 has the sheet enter the car at an                                                                is kept horizontal and simply unclipped
 angle of about 45 degrees                                                                        from the mast, then from the old guy, and
                                                                                                  is clipped onto the new guy and then re-
 The slot between the jib leech and         S                                                     attached to the mast.
 the mainsail is even all the way up                                                                   Dip Pole Gybe ­ dip pole gybes are
                                                                                                  done on boats where the spinnaker pole
 In most wind, the jib tell-tales break     S                                                     cannot easily be manhandled by the
 evenly.                                                                                          bowman (i.e. 40 foot and upwards), and
                                                                                                  the boat usually has lazy sheets/guys. The
 In strong wind, the top tell-tales break
 slightly earlier because the top of
                                            S                                                     gybe involves the bowman unclipping the
                                                                                                  pole from the guy and then the pole is
 the sail will be allowed to twist off                                                            hoisted on the mast track and dropped at
                                                                                                  the outboard end so that it is able to dip
 The jib is trimmed constantly upwind S                                                           between the mast and the forestay. As the
 according to changes in the conditions.                                                          pole comes through to the new windward
 In big breeze, the trimmer is ready to dump                                                      side, it is clipped onto the lazy guy (at this
 the sheet if the boat gets overpowered                                                           stage the sheet is still carrying all the load),
                                                                                                  the outboard end is hoisted and the new
 If the jib is up while the spinnaker is    S                                                     guy is sheeted on to take the load.
 flown, it is deliberately under-trimmed                                                               Tackline ­ used on an asymmetric
                                                                                                  spinnaker to anchor (and adjust) the
 If you feel slow, ease the jib slightly.   S                                                     tackline on the bow, bowsprit or spinnaker
 If you can't get height upwind, pull                                                             pole.
 the jib in slightly                                                                                   Spinnaker Chute ­ a spinnaker chute
                                                                                                  has an opening near the bow where the
                                                                                                  spinnaker is launched and recovered, and a
The discussion this month will be                anchored on the sheerline near the boat's        tube (made out of GRP and/or sailcloth) in
on spinnakers and will include both              shrouds. It has a block or fairlead which the    the boat to store it. To launch, the halyard is
symmetricals and asymmetrics. In addition        spinnaker sheet/guy runs through and its         pulled and to drop, the halyard is released
to dealing with how to trim them, we'll          primary purpose is to make the angle of the      and the retrieving line (an umbilical
also talk about the basics of handling them      guy coming off the spinnaker pole greater.       attached to patches near the middle of the
safely. We won't deal with individual types      This helps to prevent the pole skying (i.e.      kite) is pulled until the whole sail is stowed
of boats because the generic descriptions        shooting up vertically) and the tweaker for      in the chute. They are commonly used on
should be sufficient.                            the new guy needs to be tensioned before         dinghies and can make sail handling easier,
                                                 a gybe for this reason. The tweaker is also      although they are prone to collecting water
Definitions                                      sometimes used to help the sheet run more        when the bow goes through waves.
     Kite; Chute; Bag - other terms for          smoothly under the mainsail boom, or to               Spinnaker Bag ­ another option for
spinnaker.                                       take twist out of the leeward edge of the        launching/recovering/storing the spinnaker.
     Asymmetrical Spinnaker ­ has a              spinnaker.                                       They can take the form of the sailbag on
longer luff than leech - i.e. the clew will be        Pole Topping Lift ­ effectively a halyard   big boats (which can be used to store, and
higher than the tack. This means that the        to pull the spinnaker pole upwards.              then launch the kite) or the bags on smaller
luff is always `the luff' (on a symmetrical           Pole Downhaul ­ pulls the spinnaker         boats like Fireballs and Rebels which are
spinnaker, each vertical edge could be the       pole down.                                       located at the front of the cockpit. On
luff or the leech, depending on which gybe            Square the Spinnaker ­ on a                 dinghies, spinnaker bags may seem harder
the boat is on) and the sail gets gybed by       symmetrical spinnaker, this involves pulling     to handle than spinnaker chutes but they
releasing the sheet on the one side and          on the guy and is done when the boat             don't collect water and give more sail
pulling it in on the new leeward side.           bears off further away from the wind.            handling options.
     Symmetrical Spinnaker ­ clews are the            Lazy Sheet & Lazy Guy ­ many large               Snuffer ­ effectively a vertical spinnaker
same height and luffs are the same length.       boats (35 foot-plus) have separate sheets        chute that consists of a faired opening and
     Sheet ­ rope used to control the            and guys. The loads on the guys are much         a long bag. It is hoisted with the spinnaker
leeward side of the sail.                        bigger than on the sheets (i.e. they need        inside it, and then is allowed to open when
     Guy ­ only used on a symmetrical            much stronger rope and blocks) and also          the crew wants to set the kite. Dousing the
spinnaker. Controls the windward side            need to use an ideal sheeting position           spinnaker consists of easing the sheet and
of the sail and usually runs through the         (this will be much further forward than the      guy (or just sheet on an asymmetric) and
spinnaker pole end.                              turning block for the spinnaker sheet) which     then pulling the snuffer downwards. The
     Tweaker ­ a control which is usually        will be a combination of getting leverage        spinnaker and snuffer are then lowered

8 · SAILING March 2009                                                                                             
onto the deck. Snuffers can be useful,            boat sailing over it) or it blowing inside the
especially on large boats sailed by few           fore-triangle and getting tangled. A good
people.                                           way to prevent this is for the helmsman
    30/20 ­ refers to cloth weight. This          to bear off a bit more as the kite is being
equates to about 0.6oz but can be used in         pulled up but if the sail does get stuck
similar windstrength to a 0.75oz.                 between the forestay and the mast, a gybe
    0.5oz ­ refers to cloth weight. This will     can help to get it free.
be a light wind spinnaker. Lighter cloth will
make it easier for the spinnaker to set in                Trimming the Spinnaker
light wind. Heavier cloth will make it less
likely to burst in strong wind.                   Sheet And Guy Position
    0.75oz ­ refers to cloth weight. 0.75oz       Generally you want to have the spinnaker
is the most common weight for general             as loose as possible and you do this by
purpose spinnakers.                               keeping the sheet eased enough to have
    1.5oz ­ refers to cloth weight. 1.5oz         a constant, small curl in the luff. If you
and higher is ideal cloth for strong wind         are trimming the sail and the luff hasn't
spinnakers.                                       curled in the last 10 seconds, the odds are
    Code sails (e.g. Code 0, A1, etc.) ­ refers   that it's trimmed too tight. If the spinnaker
to sail size and whether it is asymmetric         collapses from the luff, it means it was set
(A) or symmetrical (S). Note that very            too loose. If the collapse seems to start
few Grand Prix boats carry symmetrical            from the centre, it needs to be eased and/
spinnakers anymore. Sizes are as follows:         or squared to windward.
                                                      For getting the guy in the right place,
Code 0=75% of Spinnaker Area (SPA)                the first thing is that the pole should never
Code 1=96% of SPA                                 be right on the forestay. On dinghies it
Code 2=100% of SPA                                might be as close as 5cm, while on
Code 3=90% of SPA                                 keelboats it's likely to be more like a
Code 4=75% of SPA - fuller than a code 0          minimum of 20cm. Assuming the sheet is
                                                  trimmed correctly (i.e. with the luff just
         Handling the Spinnaker                   curling), the luff of the spinnaker should fly
We'll assume that the spinnaker is stored         vertically off the pole. If it seems to bend to
in a bag so neither a chute nor snuffer           leeward, the guy is too tight and the pole is
will be used. We'll deal with handling a          over-squared, and the opposite if it tends to
symmetrical spinnaker first.                      bulge to weather.
                                                      An exception could be if the wind is
      Symmetrical Spinnaker                       very strong and you are trying to flatten the
The Leeward Hoist                                 kite, in which case a bit of over-squaring
    This is the easier of the two methods         can be a good thing, especially on a run
of getting the spinnaker up because the           when it will help to stop the boat rolling.
sail flies out to leeward (away from the
boat) and there's much less risk of getting       Pole Height                                        discussed what happens in end-for-end and
it wrapped around something, or sailing           The starting point is that the clews of the        dip-pole manoeuvres).
over it.                                          spinnaker should be roughly level. As                   * If there is lots of wind and the pole is
    In a leeward hoist, the crew will set the     a general rule, a low pole will help the           difficult to attach to the mast on the new
spinnaker pole first (a good starting point       spinnaker to set when the wind is very light       side there will probably also be waves. As
is for it to be approximately horizontal)         while a raised pole will help it `breathe'         the boat rolls to weather, the pole will be
and then the spinnaker itself will be pulled      better when there's breeze.                        a lot easier to push out and that is the ideal
up as the boat bears off from a beat. As               You can also use the point that the luff      time to clip it onto the mast.
the kite goes up, the guy will be pulled          curls to get the height right. Ideally, the curl        It's also a good idea for the bowman
back (more, the closer the boat is to dead        should start in the middle ­ if it starts at the   to push the pole out forwards rather than
downwind) and, once it is all the way up,         top, there's too much twist in the sail and        across the boat ­ there is less distance to
the sheet will be trimmed.                        the pole should be lowered. The converse           push because the forestay will already be
                                                  is true if the curl starts near the bottom.        forcing the new guy some of the way out.
                                                                                                          * The helmsman watches the progress
The Weather Hoist                                                                                    of the bowman and slows down or
When hoisting to weather, the spinnaker                     Gybing the Spinnaker
                                                  There is no reason why a spinnaker should          speeds up the gybe, depending on what's
needs to go up first (once the boat has                                                              happening on the front of the boat.
already borne away) and the pole                  stop drawing through a gybe, except
                                                  sometimes on two-person dinghies where                  * The trimmers also watch the bowman
is attached to the mast and the guy                                                                  and ensure the spinnaker is flying smoothly
afterwards.                                       the crew might run out of hands. Good
                                                  gybes involve the whole crew looking               the whole way through the gybe, taking
    On a two-person dinghy, the process                                                              particular care to ensure that they do not
will usually be that the crew takes the           forward and communicating clearly with
                                                  each other. The basic process, taking into         suddenly pull the new guy as the bowman
whole spinnaker out of its storage bag and                                                           is trying to attach it to the pole...
then throws it forward and around the             account the previous description of end-
                                                  for-end and dip-pole gybes, should be:                  Not controlling the spinnaker and
forestay as the helmsman pulls the halyard.                                                          ending up with it flapping is very bad. It
    On a keelboat, the bowman will take               * The tactician calls the gybe.
                                                      * The pre-gybe adjustments are made            will be hard to attach the pole to the new
the whole spinnaker forward and feed                                                                 guy and the flapping is likely to heel the
it around the front of the forestay as the        (e.g. the new tweaker is pulled on before
                                                  the gybe).                                         boat, potentially spinning it out of control.
pitman pulls the halyard. In both cases, the                                                              * The pitman monitors the pole
pole is only set once the spinnaker is up             * The bowman (assuming we're on a
                                                  keelboat) runs forward and braces himself          downhaul and uphaul to make sure the
and, preferably, flying.                                                                             pole is able to be controlled and then
    C o o r dinat io n b e t we e n w h o eve r   (probably against the mast) to handle the
                                                  pole.                                              squared back sufficiently on the new gybe.
is pulling the halyard and feeding the                                                                    * The old weather tweaker is released
spinnaker for ward is critical ­ bad                  * As the helmsman bears off into the
                                                  gybe, the guy trimmer squares the pole.            as the boat comes onto its new course.
coordination could result in the bag landing                                                              * Someone is ready to release the vang,
in the water in front of the boat (and the            * The pole is gybed (we have already

10 · SAILING March 2009                                                                                              
especially if there is a chance of broaching.

                             The Drop
Leeward Drop
Here, the spinnaker is pulled in on the leeward side of the boat.
The process is:
     * Get hold of the sheet by holding it directly, controlling the
leeward tweaker or using a retrieving line, and start to pull it and
the spinnaker onto the boat.
     * The guy should be eased forward but controlled, and the
person gathering the spinnaker (probably the bowman) should get
control of the foot of the sail first.
     * Note that the guy should not be eased so much that the
spinnaker gets away from the boat. Rather the guy trimmer must
watch the progress on the bow and ease on fast enough to not
slow down the bowman's job.
     * The halyard is released and the sail is gathered in as quickly
as possible.
     * Once the sail is in, the pole can be lowered and stowed.
     The leeward drop is made easier by the spinnaker ending up
in the lee of the main and jib so it is relatively easy to pull in.
However, if the foot is not under control by the time the boat
starts to head upwind, it can get away from the boat and cause a
problem (like get stuck around the aft end of the boom).
     On large boats, leeward drops are safer than weather ones.
However, on yachts up to approximately 30 foot, they are both
fairly easy and, if you are sailing a standard Olympic course, it will
probably be better to do weather drops so that you are set up for a
leeward hoist at the windward mark.

Weather Drop
The process is:
    * Drop the pole and stow it on the leeward side of the boat
(taking care to get it on the right side of the jib sheets). As the
pole is dropped, the guy is slightly over-squared to flatten the kite                                                       SAILING March 2009 · 11
                                  Symetrical spinnaker                                                 Symetrical spinnaker
                                  - setting the the pole height                                        - trimming the guy

                                            Pole end clew higher             Luff `bends' to leeward
                                            - heavy air position             - ease the guy forward             Luff `bulges' to windward
                                                                                                                - square the guy more

                                            Clews even
                                            base position

                                                                                                              Vertical luff
                                 Pole end clew lower                                                          - guy correctly trimmed
                                 - light air position

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         Spec 12, dock lines and anchor rope -
                   all cut to length.
      We now also offer a braided, racing, 3 strand
           and rope to wire splicing service.                      and give more control. If possible, someone should hold onto
             And we supply snap, `Dī and                           the weather shrouds and act as a human pole to help hold the
                                                                   spinnaker out to windward.
               captive halyard shakles.                                * If you are on a keel boat where the jib sheets run over
                                                                   everything, have someone ensure that the weather jib sheet is
                                                                   pulled tight to make it easier for the bowman to get the spinnaker
                                                                   dropped on the correct side of the jib sheets.
                                                                       * This is a simple but very effective way to ensure that the jib
                                                                   sheets are always over everything else.
                                                                       * The bowman gets hold of the guy and starts to pull it onto
                                                                   the boat. At this point, the sheet needs to be eased and the crew
                                                                   gathering the kite MUST get control of the foot before the halyard
                                                                   is eased too much - i.e. this means that everyone is looking
                                                                   forward and making sure that the spinnaker does not land up in
                                                                   the water in front of the boat.
                                                                       * The cool thing with the weather drop is that once the kite
        6-8 Moss Road Westmead                                     is mostly under control, the helmsman can head up as he/she
                                                                   pleases because the spinnaker will get blown into (as opposed to
              Ph 031 700 4525                                      away from) the boat.
          Fax 031 700 2908/55
                                                                                    Asymmetrical Spinnaker
      Email:                                The Hoist
                                                                   The critical point when hoisting an asymmetric is that, on boats                                             which have them, the bowsprit needs to be pulled out all the way
                                                                   before anything else happens. If you try to pull the bowsprit out

12 · SAILING March 2009                                                                                    
once the spinnaker is up and the tackline is    sailing in waves this will eventually result in
                                                                                                  Checklist                              True?
set, the odds are that the loads will be too    the kite losing its `balance' and collapsing
high to do so.                                  completely.
                                                                                                  You know what the different             S
                                                                                                  spinnaker controls do.
     The next thing is to pull the tackline
and then the halyard. Apart from that,           Gybing the Asymmetrical Spinnaker
it is the same as hoisting a symmetrical        For the most part, this involves releasing
                                                                                                  You know which spinnakers you
                                                                                                  have in your inventory and why.
spinnaker.                                      the old sheet and pulling in the new one.
                                                In light wind, the spinnaker can `float' most
       Trimming the Asymmetrical                of the way around and should not need to
                                                                                                  You know the difference between
                                                                                                  a leeward and weather hoist and
              Spinnaker                         collapse. However, in breeze, you probably
                                                                                                  can do either.
                                                don't want to come out of the gybe with
Sheet and Tackline Position                     the spinnaker too powered up. In this case,
Like a symmetrical spinnaker, the objective     it can be good to collapse it on the jib just
                                                                                                  On a symmetrical spinnaker, the
                                                                                                  luff flies vertically up the luff.
with the asymmetric is to keep a bit of curl    as you're going through the gybe. This is
on the luff at all times and try and keep the   achieved by giving a quick jerk on the old
sheet as loose as possible.                     sheet as the boat gets to dead downwind.
                                                                                                  On a symmetrical and asymmetric         S
    On boats with fixed bowsprits (or if the                                                      spinnaker, the sheet is frequently
                                                The sail can then be pulled through to the
spinnaker is just flown off the bow), you                                                         adjusted and the luff curls evenly
                                                new side once the mainsail has gybed and
obviously don't have a pole to square and                                                         the whole way up.
                                                the boat is on its new course.
this could make sailing lower than a beam
reach pretty difficult. However, sailmakers     The Drop
                                                                                                  In light wind, the pole or the
                                                                                                  tackline is lowered.
ar e go o d at making a s y mm e t ric al       This is the almost same as for a symmetrical
spinnakers for heavy keelboats (high speed      spinnaker, the main difference being that
skiffs don't have the problem because their                                                       In strong wind, the pole and the        S
                                                the pole is the last thing to be stowed
apparent wind is always so far forward) and                                                       tackline are raised.
                                                irrespective of whether you're doing a
the sails are designed to be able to `float'    leeward or windward drop. It was the first
around to windward with a massively                                                               You've practised gybing the             S
                                                thing to be launched in the hoist and the
eased sheet.                                                                                      spinnaker and can do it in an
                                                order is reversed for the drop. The other
    The tackline performs a very important                                                         condition you're likely to sail in.
                                                point is that it is very easy to get the kite
role (beyond just pulling the kite to the       in the water, especially if it is being flown
end of the pole) and should actually be         off a bowsprit (which is physically very
                                                                                                  You know the difference between         S
trimmed like the pole uphaul/downhaul                                                             a leeward and weather drop and
                                                close to the water). This means that getting
on a symmetrical spinnaker ­ i.e. eased to                                                        can do either.
                                                the spinnaker onto the boat very quickly
allow the tack to go higher in breeze and       is extremely important. On bigger boats,
tightened when the wind drops. When                                                               If there's anything you'd like to
                                                it has resulted in techniques like pulling
there's lots of wind, an eased tackline                                                           discuss about spinnaker trim or any
                                                the spinnaker through the gap between
can also help to get the spinnaker to float                                                       of the other topics we've covered so
                                                the boom and the loose-footed mainsail to
further to windward, although if you're                                                           far, give Mark a call on 072-140 9049.
                                                help keep it high and out the water.                                                                                                SAILING March 2009 · 13

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