RIGHT TO STAY PUT
2011 Tor Pinney - All Rights Reserved
Positioning and Setting Techniques
Over the years I’ve seen a lot of boats drag anchor, usually in
squalls, but sometimes in perfectly mild conditions. Anchoring
poorly not only endangers your own boat, but every other vessel
in the harbor. Even if your hook does usually hold, take a
moment now to review these simple anchoring techniques to be
sure your boat will stay where you put her, every time.
Anchors, chain, line and shackles need to be of a size
suitable to the vessel. As a rough guideline for sailboats of
moderate displacement, your primary bow anchor ought to weigh
about 1-lb. per foot of boat length. Err on the larger side. One
additional bow anchor of equal or greater weight (and preferably
of a different design) should also be carried, ready to deploy
with its rode attached. A third anchor plus a half-weight stern
hook is normal aboard boats that cruise. Keep each rode’s bitter
end secured to the vessel.
An anchor needs to have some appropriately sized galvanized
chain between it and the nylon anchor line, no less than 15 or
20 ft; more is better. Most experienced cruising sailors fit at
least one of their bow anchors with an all chain rode, often
using a windlass with a chain gypsy to handle it. A windlass,
especially an electric windlass, not only spares back muscles,
but also promotes safer anchoring by encouraging the crew to
re-anchor as many times as it takes to achieve a perfect set.
As you approach an anchorage, check that the anchors you plan
to use are ready to be lowered and that the rodes will run free.
If you're towing a dinghy astern, shorten up on the painter so
that it can't reach the propeller when you're backing down.
Explain to your crewmembers what's expected of them, assigning
duties and deck positions. Establish a few simple hand signals
(see illustration) so that the helmsman and the anchor handler
can communicate without shouting back and forth. Depending on
who's calling the shots, the helmsman may need to express
commands to "let go (or retrieve) the anchor", "feed out more
scope", and "snub or cleat off the rode." The anchor handler
needs signals to request forward, neutral, and reverse gears,
and more or less engine throttle. One husband-wife team I know
even has a signal for "calm down, dear!"
Enter the harbor slowly and observe how the boats there are
anchored. Most of them may be lying to a single hook, but some
might have two anchors set off the bow, or even one off the bow
and one astern. Some may be riding on permanent moorings. When
the wind or current shifts, these boats will all respond
differently. The vessel with two bow anchors set will swing in a
shorter radius than boats on a single hook.
Vessels anchored fore and aft won't swing at all. Those on
permanent moorings will pivot around their bows, but move
very little. In light airs, boats with all chain rodes may
not swing as far or as quickly as those riding to a mostly
nylon rode. You, as the newest arrival, must anchor to keep
clear of vessels already there, anchoring your boat to
accommodate any change in wind direction and strength. This
often means imitating the anchor pattern of your neighbors,
or else keeping far enough away to allow room for a
different anchor plan. It's always preferable to leave extra
space around your boat. Be sure you wind up no less than 3
boat lengths ahead of the nearest boat behind you. More is
safer and more courteous.
Now that you’ve checked out the neighborhood, position your
boat bow to the wind (or the current, if that's the stronger
force), right about where you want to end up once you're
anchored, roughly equidistant from your nearest neighbors. Sound
the depth and be sure you'll have ample water beneath you at low
Next, motor slowly ahead a distance of about 7-times the depth
reading you just took and take a new sounding. This number will
help you determine how much anchor rode you’ll need to put out.
A safe minimum anchor rode length in normal weather conditions
is a 7 to 1 ratio of rode length to depth; 5 to 1 for an all
chain rode. "Depth" in this case is the actual depth of the
water at high tide, plus the height above the
water's surface of the hawse or bow roller, the point at which
the rode leaves the boat.
scope = (depth
at high tide + hawse height) x 7
So if high water is 20 ft. deep, and your bow roller is 5 ft.
above the water, the total “depth” is 25’. You'll want to use
175 ft. (25 ft. x 7) of line-plus-chain anchor rode in average
conditions, or 125’ of all chain. Mark your anchor rodes in 20-
or 25-foot increments to facilitate reading rode length as you
feed it out.
If you anticipate a blow, a ten to one scope isn't too much to
pay out. To the extent that harbor space permits, the heavy
weather rule is the more scope the better. Putting out too
little scope is one of the most common mistakes skippers make
when anchoring. Later, they wonder why the boat dragged during a
While still hovering above the spot where you intend to lower
the anchor, look around. Don't set your anchor close alongside
or close off the bows of another vessel. If you do and the wind
shifts, you may swing into her, or she into you. Either way
you'll be responsible for any damage, being the last to have
anchored. It is usually safe, however, to set an anchor a few
boat lengths astern of another boat, or off her quarter, as long
as you’re both using the same anchor pattern and scope ratio.
Note where the rodes of nearby boats are pointing. A boat may
have a second anchor set off in your direction, which you could
foul if you drop yours on top. If the harbor winds are light or
if a tidal current is running, don't assume that everyone's
anchor is positioned straight out in front of them. In such
conditions anchor rodes - especially chains - may veer off in
any direction on the bottom. If in doubt ask any skippers you
see aboard nearby boats where their anchors lie. If the water’s
clear, look and see for your self.
Setting the Hook
If everything appears to be all right, circle back around to
your intended final resting spot and then drive slowly forward,
approximately the distance of your pre-calculated scope. Here,
stop the vessel completely with a short burst of reverse power.
Do not drop the hook while the boat is still moving forward. If
you do, your anchor chain will drag over the anchor when the
boat drops back and may foul.
When you let go the anchor, don't allow the rode to run
screaming out. Rather, lower the anchor quickly but with
control, paying out the rode through gloved hands, or hand over
hand, or with your windlass until you feel the anchor rest on
the bottom. As the anchor is lowering, the helmsman can shift
the engine into idle reverse so that the vessel just begins
making sternway about the time the anchor reaches the bottom. If
it's windy, leave the engine in neutral and let the boat's
windage provide the backing propulsion. Pay out the rode as the
boat continues to back slowly, maintaining a slight tension on
it so that it lays out straight on the bottom rather than piling
up. Keep the boat's reversing speed to a bare minimum.
Once you’ve fed out about half of the intended scope, with the
boat still backing slowly tighten your grip on the rode until
you feel the slack taken up and the anchor tug. Then let the
line feed out a bit more, again keeping a light tension on it.
If your grip isn't strong enough for this, pass the line under
the horn of a deck cleat to make it easier to hold. Snub up
firmly, not long enough to drag the anchor along on the bottom
but 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 rode and heavier ground tackle it may
be necessary to use the windlass gypsy for this, alternately
braking and releasing the drum.
This gentle snubbing and feeding of the rode while backing the
boat is the surest way I know to make an anchor set, even in
difficult holding ground, yet it is a technique that few sailors
seem to appreciate. It gives the anchor an opportunity to right
itself, penetrate the bottom surface, and dig in gradually. It
also keeps the rode clear of most bottom debris and helps keep
the vessel's bow from falling off the wind. Usually, even before
the scope is completely paid out you can feel that the anchor
When you've laid out the prescribed amount of scope, make fast
the rode while the boat is still reversing at idle speed. If the
hook has taken hold, the boat will come up short on the rode and
stop, setting the anchor even more firmly. You'll feel the
vessel stop backing and, in a moment, spring forward slightly on
Now that the anchor seems to be set, make sure it’ll hold if
the wind gets up. Select a range abeam of you, two
stationary objects preferably on shore, one father
away than the other but more or less lined up with
each other, such as a dock piling with a building
beyond, a prominent rock and a tree, or whatever's
handy. With the engine in reverse, raise the throttle
a few hundred RPM above idle. Keep your eyes on the
range abeam. You'll see by its movement that the boat
is beginning to make sternway as the rode stretches
out. If the anchor is truly set, you will then feel
the boat come to an abrupt halt when the rode becomes
taught. The range points will verify this by ceasing
to move in relation to each other. Still watching the
range, increase the throttle to around half full
astern, ensuring that the anchor will indeed hold
under stress. After 15 or 20 seconds, ease up on the
throttle and let the engine idle in reverse a few
seconds before shifting into neutral. This allows the
anchor rode to relax without it springing the boat
forward. A prudent skipper will now repeat the power
set at least one more time before cutting the engine.
If, however, the range continues to shift while you're backing
down, then the anchor is dragging. If it drags more than a few
yards without setting, you'll have to retrieve it and repeat the
entire anchoring sequence. In harbors with rocky or grassy beds
where the water is clear enough to see, it pays to visually
locate clear patches on the bottom into which an anchor can be
lowered to set more readily.
No matter how good your technique, some bottoms are simply
poor holding and may require repeated attempts to set the hook.
Failing that, try using your other bow anchor instead. It should
be a different design than the primary anchor and may fare
better in that particular bottom. Occasionally you may retrieve
an anchor and discover that it has fouled itself in an old car
tire, fish net or bucket, in which case it never would have set
or held the boat.
A Few More Tricks
Whenever possible, take a look at your anchor after it is set.
Following your rode from the vessel's bow, swim or dinghy over
the anchor and look at it through a facemask or a glass-bottom
bucket. If you're a strong swimmer you can dive down and hand
set a partially set hook by forcefully jamming the point into
the bottom several times. Afterwards, observe it from the
surface while your mate backs down with the boat’s auxiliary
engine. You'll see the anchor dig itself in deeper. This is the
most foolproof method there is to ensure an anchor is set.
If because of restricted harbor space you have to anchor with
a little less than optimal scope, you can enhance the holding
power of your ground tackle by weighing down the anchor rode.
This calls for a sizeable lead weight to be shackled loosely
around the rode at the stemhead after the anchor has been set,
so that it can slide down the line. Tether the weight with a
retrieving line to control how far it travels, and to retrieve
it before weighing anchor. Then lower the weight onto or near
the harbor floor. The boat tugging on the anchor rode must
overcome and lift the weight before putting any significant
pulling force on the anchor itself. Even then, the initial angle
of pull will be more nearly horizontal, which is what you would
have accomplished had you been able to use more scope. This
technique is no replacement for adequate scope in winds strong
enough to straighten the weighted rode, but it may be useful for
a stopover in a crowded harbor in settled weather.
If there's a possibility of inclement weather or of a wind
shift that would swing the boat into danger, then a second bow
anchor is called for. Many prudent skippers always set two
anchors as a matter of course. This doesn't mean you have to get
into the dinghy and row out with an anchor and a pile of chain,
something I've often seen novices do. Instead, simply determine
where you want the second anchor to be and drive your vessel
over there. You'll have to temporarily pay out a bunch of extra
rode on your first anchor to do this, and take it back in once
the second hook is set. Place the second anchor so its rode will
form an angle of around 60° from the first, or else set it in
the direction of the most likely or most threatening wind shift.
Use the same snub-and-feed and power set techniques described
What I’ve discussed here isn’t the only way to anchor a boat.
Placing a stern anchor to keep a boat from swinging altogether
can be done by paying out and, afterwards, retrieving lots of
extra bow anchor rode, or by carrying out the half-weight stern
hook in the dinghy. There’s also the Bahamian moor - 2 anchors
set 180° apart for strong, reversing currents - anchoring “on
the fly” - dropping a bow anchor while coasting forward, feeding
out the scope and then snubbing the rode to stop the boat and
set the hook - and other variations. Still, the same principles
Anchoring a boat securely is one of the most basic and most
important boating skills. Practice doing it correctly, with
forethought, technique, control and confidence, and we'll all
sleep easier in port.
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