are anchor weights, kellets, sentinels so effective?
notes translated into French
to anchor a boat
Anchoring your boat securely is one of the most
basic skills in boat handling. Learn to set an
anchor right, with control and confidence, and
we will all sleep easier. Anchoring poorly
endangers not only your boat, but also the other
boats anchored nearby. So, even if your
anchoring technique is good, it is wise to
review these tips.
your anchor has not set securely or you have
anchored on foul ground, there is a high chance
of the anchor dragging. Even when this happens, an
Anchor Buddy anchor weight will give the anchor
another chance to dig in as it keeps the chain
on the seabed.
boat’s primary ground tackle - anchors, chain,
warp and shackles, must be of a size considered
adequate for the size and weight of your vessel.
(Check with the manufacturer’s
recommendations). To maximize holding power, an
anchor needs to have some sturdy galvanized
chain between it and the anchor line, no less
than 4.5m - 6m (15-20ft). It should be at least the
length of the vessel. The warp or chain if
all-chain is used, should run free in the anchor
locker and the bitter end should be fastened to
the vessel. It is a good idea to have the warp
or chain marked off in 3m - 6m (10-15ft) increments
to be sure how much is being let out, when
aware! See the Rocna
nearing an anchorage, shorten up the painter if
you are towing a dinghy, so it cannot possibly
reach the propeller when backing the vessel.
sure crew members know what is expected of them.
Remember, it is almost impossible to hear
commands from the bow in the cockpit, so a few
simple hand signals should be established.
in the bay, consider how the boats already there
are anchored. Most will be swinging on a single
anchor warp. But in heavy weather, some may be
using an anchor weight, some may have two
anchors set off the bow, or one off the bow and
one set astern. Some may be on permanent
moorings. When the wind or current shifts, the
vessel with an anchor weight or two bow anchors
set, will swing in a shorter radius than boats
on a single anchor. Vessels anchored fore and
aft won’t swing at all. Those on permanent
moorings will pivot around their bows, but move
very little. In very light air, boats with all
chain anchoring systems may not swing as far or
as quickly as those riding a mostly nylon warp.
the newest arrival, you must anchor to keep
clear of boats already at anchor. Make sure you
allow for any change in wind direction and
strength. It is always safer to leave extra
space around your boat.
your boat with the bow to the wind (or the
current, if that is stronger), roughly
equidistant from your nearest neighbors in the
approximate location you wish to be in when
anchored. Make sure you will have ample water
beneath you at dead low tide.
normal conditions, a safe minimum anchor scope
ratio is 5 to 1 (warp
or chain length to depth). In heavy weather 7
to 1 or more. Depth is the depth of water at
high tide, plus the height from water line to
the bow roller. Scope is the actual amount of
anchor line paid out when the boat is safely
anchored. For example, if high water is 20ft
deep and your bow roller is 5ft above the water,
you need 125ft (i.e. 5 times 20 + 5ft) of scope
putting out too little scope is one of the most
common mistakes a skipper makes when anchoring.
still hovering above the spot where you intend
to lower your anchor, take another look around
your boat. Don’t set your anchor close
alongside or close off the bows of other
vessels. If you do, you may well swing into them
if there is a wind shift. It is usually safe to
set an anchor close astern or off the quarter of
another boat. Look also at the direction in
which the warps and chains of nearby boats are
pointing. A boat may have a second anchor set
off in your direction, which you may foul if
your anchor drops on top.
winds are very light, don’t assume that
everyone’s anchor is positioned straight out
before the bow. In calm conditions, anchor
warps, especially chains, may be stretched out
in the direction the last real breeze blew from.
You can always ask the skipper of a nearby boat
where his anchor lies.
all is well, circle back around to your intended
final resting spot and then slowly coast forward
the approximate distance of your planned scope.
the vessel completely with a short burst of
reverse power. When your vessel has lost all
way and is at a complete halt, lower the anchor.
If you have any way on at all, your anchor chain
will drag over the anchor, once the boat drops
back and may foul the anchor.
you let go the anchor, don’t let the chain and
warp go screaming out to pile on itself.
Instead, lower the anchor quickly, paying out
the warp or chain hand over hand or with the
windlass, until you feel the anchor rest on the
seabed. Signal to the helmsperson to put the
engine in very slow reverse, so the vessel just
begins to make slight stern-way about the time
the anchor touches the bottom. If it is windy,
leave the engine in neutral and let the boat’s
windage and motion provide the backing
propulsion. As the boat continues to back
slowly, also feed out the anchor line (be it
warp or all chain) slowly, maintaining a slight
tension on it, so that it is laying out straight
on the seabed, instead of in a pile.
the boat still backing slowly and with about
half of the scope out, hold the anchor line
firmly until you feel the slack is taken up and
the anchor is tugging. Feed more anchor line
out, but keep tension on so the anchor is being
the anchor line around the bollard to make it
easier to hold. Snub up firmly, just long enough
to feel it tugging for a second, then ease off.
Repeat this snub and feed pattern several times.
On a larger vessel, with an all chain anchor
line and heavy ground tackle, you would be using
the windlass gypsy for this task, alternatively
braking and releasing the drum.
gentle snubbing/feeding action while backing
down the boat is the surest way to make an
anchor set. Yet it is a technique very few
skippers seem to employ. It gives the anchor an
opportunity to right itself, penetrate the
bottom surface and gradually dig in.
the anchor has taken hold, the boat will come to
an abrupt halt, firmly setting the anchor.
However as we all know, there are times when you
do worry whether the anchor is holding. It can
roll out and dislodge in vicious wind gusts and
squalls or very strong wind and when your boat
is swinging wildly. These conditions are
often unexpected and are cause for concern.
anchors drag and
you can do to reduce the risk
from boats that have faced whole gale to cyclone
winds at anchor, say that it is not the winds
that break anchor gear and upset anchors, but
the accompanying wave action which causes boats
to pitch, surge, heave and yaw. Surge is the
worst of these motions as the boat rides over
the waves alternately stretching and relaxing
the anchor warp like a horizontal yo-yo. Surging
of the boat sometimes as much as doubles the
loads felt from wind drag alone. The surge
factor can be proportioned to the boat
displacement and length. Surge is the motion
forward and backward in the direction of boat
travel, along the longitudinal axis.
other 5 motions experienced by a boat at anchor
are sway, heave, roll, pitch and yaw. The wind
tends to create yawing and swaying, the waves
tend to create pitching and heaving, while the
anchor restraint, depending on its elasticity,
is involved with surging.
Royal Navy's test*
on why anchors drag "...if the
angle of pull is 10 degrees off the seabed, the
anchor's maximum holding power is down to 60%. At 15
degrees, it is further reduced to only 40% of its
maximum holding power".
*Information sourced from Admiralty Manual of
Seamanship. Vol. 2
an anchor weight reduces the chance of the
'new generation' anchor designer says
improvements to the performance of the current
day anchors means they do everything an anchor
weight can - as long as you choose a larger one
than specified. We hear horror stories at boat
shows. Read why anchor weights
have been around for over 2000 years and
how they can enhance the
anchor's performance and make life at anchor
safer and more comfortable
When you need extra security at anchor, reduce
the maximum anchor load nearly 50 per cent* with an Anchor Buddy anchor weight.
In a very early edition of his book, Piloting
Seamanship and Small Boat Handling, Charles F.
Chapman says "If
you have reason to doubt that your main anchor
is going to hold in a heavy blow, you can
increase its holding power by sending a kellet
or sentinel down the anchor line...."
Reduced risk of dragging - considerably less
swing - far more comfort.
Peace of mind and the finest guarantee of a
good night's sleep......
Eade, world sailor of 130,000 sea miles
"Quite good' is a total understatement.
It is totally amazing in all conditions and at
all times; light winds or heavy weather and so
easy to put on and off after you understand
how to do it.
The advantages it gave to our comfort on
board and the reduction in our swing circle
were so good that we would use it all the time
whether we needed it or not and we would never
leave the boat without setting the Anchor
the full letter
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