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by Bill Deeley, long standing Cherub Sailor & Designer.
Before you sailed a Cherub, you probably thought that upwind
was the hard bit - Wrong Again. Most people, provided
they don't mess up the tacks, will arrive at the windward mark
sooner or later. The shock comes the first time you bear away
only to see the entire foredeck disappear below the water, so
a few basic points:-
1. Cherubs are very short of length, and are therefore just as
inclined to fall over forwards as sideways, and you will therefore
have to position your ballast (you) as far behind the transom
as possible.
2. Cherubs also go mega-fast, and steering errors are fatal. The
cretin holding the stick at the back should therefore attach himself
to the boat as solidly as possible in order to maintain control.
Short of a six-inch nail through a painful place, the best way
is to get thoroughly sat out, bum over the side, and let the crew
do any leaping about. At these speeds you can't leap about fast
enough anyway, so balance is achieved mainly using steering and
sail trim.
3. The wag who coined the phrase "keep your weather eye open"
obviously never tried a Cherub down a two-sail reach. Helms will
soon discover that a torrent of stingy white stuff makes a beeline
for the "weather eye", causing total blindness and dislodging
your contact lens. The Deeley principle is "keep your weather
eye closed, and your leeward eye open". This works much better
as the leeward eye is offered considerable protection by the hooter
- the bigger the hooter the better it works.
4. Crews need to adapt a bit too. Unless you're Alex Windsor you
won't stay on the side of the boat with your feet together. Don't
try trapezing too low - its harder to get in and out, and you'll
get knocked off by the waves. Balance is crucial, but beware of
over-compensating. Cherubs don't roll, they are either steady
or capsized. The thing you will be trying to achieve is dynamic
Balance. It's a bit like riding a bike. Statically it would fall
over, but the faster you go the easier the balance becomes, provided
you stay in control and do the right things. Crew co-ordination
and timing are essential.
Getting successfully from the beat to the reach is surprisingly
difficult. As you approach the weather mark, both helm: and crew
should shuffle back in the boat. Get the boat bolt upright and
don't be too hasty. Steadily ease both sheets as you bear away.
Don't force yourself to have to use too much rudder, as this won't
work.
All the marks always cause problems, and it is worth sticking
to a couple of basic principles. The first is to keep clear of
other boats. Boats always get close at marks, and close encounters
rapidly start to cut down the options available. Tactical advantage
is pretty meaningless if it is blowing hard enough, and the priority
is to be able to round the mark the way you want to. The second
principle is to plan mark rounding before you get there. The classic
case is when you are broad 3-sail reaching up to the wing mark
with a gybe and a tight 3-sail reach to come. Work your way up
to windward of the mark, gybe at your leisure, and approach the
mark flat-out on the new tack.
You will be 2-sailing a reach either because it is too close
to hold the kite, or if it is broader, because it is simply blowing
too hard or the waves are too big. The two cases are rather different.
The close 2-sail reach is in some ways easier, because you are
very unlikely to succumb to a terminal nose-dive. It tends to
be hell for the helm however, as spray production is at its maximum
and vast amounts of mainsheet trimming are required. This is a
time where the crew trimming the sail really can pay off as out
on the trapeze is also out of the worst of the spray. The centreboard
needs to be about a foot up, but this can be a problem if you
have come directly from a beat and the crew is still flat out
on the wire. In any case, keep the boat dead upright (mainly with
sail trim) to reduce the inevitable weather helm. Correct jib
trim is vital, as under or over trimming both lead to excessive
weather helm. The standard technique of bearing off in gusts and
heading up in lulls is not always very effective, and the straight
line course is often the best. If you are getting overpowered,
flatten the mainsail (clew outhaul and tack downhaul and let it
twist off at the top (kicker). You will only be 2-sailing a broad
reach if it is real Armageddon time. This is the worst condition
for nose-diving (see later), and without the spinnaker the boat
is badly balanced. Again, plate about a foot up, and flatten the
mainsail. It is essential that the helm maintains control here,
so get yourself jammed onto that back windward corner. The crew
should also be well back and should do all the leaping about.
Boat dead flat again. Heel to leeward causes huge weather helm
and the danger of a broach, and heel to weather forces the helm
into the boat making steering impossible due to the acute angle
between tiller and extension. Keep playing those sheets - No
Cleating. if the crew can trapeze without causing nose-dives
or getting knocked off by the waves, you can have some real fun
giving it the old "bearing off in the gusts and catching
the waves" bit. If things get really bad though, you will
be better off with both helm and crew sitting out over the back
corner. But watch that heel, there's no way you'll survive a broach
with the crew five feet away from that beloved trapeze wire.
This, believe it or not, is a real doddle once you get the
hang of it. The 3-sail reaching itself is far easier than 2-sail
reaching, the only flies in the ointment being hoisting, gybing
and lowering the kite. The hoist should be carried out step by
step, keeping control of the boat all the time. Pole on first
(helm on transom to balance), hoist kite, trim guy (get it right
first time), then sheet. I find it is best to bear away to a very
broad reach (not a run, that's too unstable), as this allows a
quicker, snag-free hoist. As soon as the crew has the guy set
up, start heading up. The crew goes for the trapeze taking the
sheet, and you're away. Of course it's easier for the asymmetric
boys, just stay at the back of the boat, bear off onto a broad
reach, and pull the strings. The drop is done the same way. Give
yourself room to bear away, crew in from the wire, kite into the
chute, and pole off. Don't drop the sheets under the bows! 3-sail
reaching a Cherub is the business, especially when you compare
it with other so-called "high performance" boats. If
things look a bit tight, the centreboard should be about a foot
up; if it's broader maybe 18 inches. The pole should be just a
couple of inches off the forestay. The best thing is that the
combination of big kite and long pole/bowsprit gives the boat
completely neutral helm, making bearing away and heading up dead
easy. The kite also lifts the bows, reducing the tendency to nose-dive.
The neutral helm allows you to get completely carried away with
steering up and down in the gusts, although this requires vast
amounts of spinnaker sheet playing - crew biceps and ratchet blocks
are at a premium. In fact, bearing off in the gusts is virtually
automatic - dump the mainsheet as the gust hits and off the boat
goes on its own!
It is surprising just how much wind you can handle with the kite
up, and it gets interesting when you start to catch and overtake
waves. This comes as something of a culture shock at first, but
just try not to bottle out. Both helm and crew need to be thoroughly
attached to the boat as the deceleration as you skip from wave
to wave can be dramatic. I ended up doing this in the last races
at Portsmouth in both '83 & '84 - lying 2nd, nothing to lose,
everything to gain and the wind blowing a gale. We gained huge
distances on both occasions; we failed to win, but it was good
fun, especially in the bar afterwards!
Most beginners lose out when they are hard pressed to make a mark,
and have to start to dump power. The first rule is not to let
the spinnaker collapse under any circumstances. Losing power starts
with the mainsail. Flatten it with the clew outhaul, then let
it twist a lot; remember that the bottom of the sail is being
backwinded by the kite while the top is in free air. Bending the
mast by means of the cunningham/tack downhaul is an effective
way of getting the rig to twist more, but letting the kicker off
is quickest! Next ease the mainsheet, but this will be limited
by the rapidly increasing lee-helm. At the same time, the crew
can let the kite luff curl back a bit, but don't let it collapse.
The boat can be allowed to heel a bit; although you will slow
down, this will help restore neutral helm and allow you to point
higher. The final and best trick of all is to let the jib out
- not Just a bit, let it flap completely. This works a treat.
Oh, the crew left the jib sheet in the bottom corner of the cockpit?
What hard luck!
Those of you with asymmetrics can ignore this bit unless it
is howling so badly that you daren't stick the kite up at all.
The real danger for you is that the transition between sitting
on the side with the kite blanketed and being blown flat by the
kite filling can get quite narrow. However even for those with
conventionals it is probably faster and safer to sail the runs
as two broad reaches unless you are absolutely clapped out and
need a bit of a rest (relative term!). The run is a bit less physical,
but it more than makes up for it in nervous stress. Whether or
not you have the kite up makes little difference, although it
does cut down on the nosedives, but hoisting and dropping may
cause problems. I don't much like dead runs as they cut down the
steering options (can't bear off) and the boat is less stable.
The best heading seems to be about 10 or 15 degrees off the dead
run. This has the additional advantage that the gybe can be made
at an opportune moment part way down the run, rather than at one
of the marks. In order to improve stability, the helm and crew
should be as far apart sideways as possible. The helm should get
fixed to the usual back windward corner, and the crew should do
the leaping about. In particular, the crew should avoid the natural
tendency to go for the weather gunwale, as this forces the helm
into the boat, inviting an uncontrollable weather roll. If it
is really blowing, the crew can get into the back of the cockpit,
behind the mainsheet and opposite the helm. This works very well,
but avoid broaching, or you will be in big trouble.
I spent a whole season in 1978, and another in 1983, falling
in on every gybe, and it wasn't until 1984 that I realised why.
Gybing is like that; you get it either right or wrong, and there
is no in-between. The key thing, after ignoring what the books
say, is to go into the gybe right. Go into it right, and you will
get away with it. Go into it wrong, and you will need divine intervention.
Starting with a 2-sail gybe, get the boat at maximum speed. This
means a reach, and it means sitting out hard. Wait for a good
wave, and go for it so that the bows will be out of the water
during the gybe. Don't move across the boat too soon, as this
will cause the boat to heel, giving enormous weather helm and
big problems. In fact, you should almost roll gybe (honest!).
The helm should move across first, so that tiller and sheet hands
are changed over before the boom comes across. Don't rely on the
crew getting the boom over; I usually sheet in some mainsheet
as I start to move across. That also gives you some sheet to release
to lessen the impact of the shock when the boom flies. A 3-sail
gybe is really no different. Go for the maximum speed right up
to the gybe, don't start fiddling with the kite. All the sorting
out is done afterwards. It helps if, after the gybe, the helm
pulls in the retriever line and the old guy (new sheet) to stop
the spinnaker flying everywhere. Don't try heading up until the
kite is fully set. Asymmetrics have it easy again of course, head
into the gybe flat out, get the main across, and don't try to
point up until you're fully sorted out. In either case its important
to keep the kite drawing as much as possible, because the spinnaker
will take much of the load off the main and keep the speed up,
both of which make the gybe that much easier.
Of course this happens when you simply get it wrong, or are
hit by a massive gust. However there are a couple of specific
high speed problems that are worth being aware of. The first is
rudder ventilation. Sometimes incorrectly called cavitation, this
occurs when the pressure differences caused by the rudder's operation
suck air down the side of the foil from the surface. You can tell
this has happened because the steering goes very light whilst
there is still hull in the water. About the only thing you can
do is to return the rudder to a central position and dump power.
Like a skid in a car or bike, if you try and turn more it will
just make the situation worse.
Its really caused by an inappropriate rudder section, be it the
one you've built yourself or the one that was made by the bloke
who specialises in Enterprise blades. The rudder stalling, like
an aeroplane wing or an oversheeted sail has similar effects,
although the feel is different.
The topic of foil design (and much else of immediate interest
and relevance to Cherub sailing) is extensively covered in Frank
Bethwaite's book "High Performance Sailing, ISBN 1 83510
757 3. All else being equal a fat section is prone to ventilation,
and a thin section to stalling, but the leading edge is particularly
important. In particular roughness scratching and uneveness in
the leding edge can make an otherwise satisfactory shape perform
badly, so keep that blade in good order. Obviously there's an
awful lot more to rudder sections than this. All else being equal,
the larger the blade the less likely you are to have problems
because you need less of an angle on the rudder for it to have
the given effect, and so it can have a thinner section. Of course
if you make the rudder big enough you'll never go fast enough
to have any problems at all.
A new problem that has surfaced in recent years is that of the
boat just taking off. There are no easy cures for this one unfortunately.
Some designs seem more prone to it than others, notably wider
sterned boats. It seems to be made worse by the extra lift that
asymettric kites develop. Occasionally if you're unlucky with
a combination of wind and waves downwind, whilst you're racing
along with the bow in the air the stern joins it too. Everything
goes quiet, and the steering goes light as there is very little
foil left in the water. Of course this only happens for a few
tenths of a second until you rejoin the water. The problem is
the landing. Cherubs, unlike shortboards, are not especially controllable
in mid air, and no-one seems to have developed the art. If you're
lucky you'll keep sailing, if you're unlucky its major pitchpole
or even breakage time.
This is dependent on your hull design, rig design and crew
weight, and varies a lot with wind and sea conditions, but all
Cherubs do it. The first, and obvious, solution is to get to the
back of the boat. One theory I have heard is to pump rapidly as
you go into the nose-dive - I've never found this works, and frankly
don't see why it should. You will often find that bearing away
will promote a nose-dive while heading up will get you out of
it. Under these circumstances, you should bear off in the lulls
and head up in the gusts, in order to make the next mark. The
generally accepted wisdom is that nose-diving is more of a problem
in waves, but I think this is wrong, at least when you become
more competent. For every bit of wave that goes up, there's a
bit that goes down, and if you sail a slalom course through the
gaps you will often get away with it. This option just doesn't
exist on flat water, and I've always found this more difficult.
Some designs, usually the finer bow ones, will go into quite dramatic
semi-nose-dives without slowing down too much. In these cases,
it is a matter of experience knowing just how far you can let
it go before bottling out. When the nose-dive is looking pretty
terminal (waterline back to the mast!), the crew can dump either
the jib or the kite. This is a last resort, as it will produce
vast amounts of weather helm and possibly a broach. There are
two types of capsize. The usual one is the slow one, bows in the
water, rudder up in the air, and the boat just falls over sideways.
As you become more experienced, this one becomes easier to avoid.
The real goodie is the true pitch-pole, which is much rarer, but
completely unavoidable as it happens so quickly. The bows go in,
the boat decelerates very rapidly throwing both helm and crew
forwards, the mast hits the water with the boat stern up, and
one usually head-butts the mast at around spreader level.
In writing this, I've realised what the key principle is - keep as many options open as possible at all times. Mistakes and problems usually happen when you get down to your last option - the forced gybe, the enforced luff by another competitor when you're in a mess with the kite, etc. This doesn't mean fudging decisions, but it does mean that you are more likely to be able to accomplish the dodgy manoeuvres under the least unfavourable conditions
Bill Deeley (written about 1985) (slightly adapted and updated by Jim Champ, 1993).
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