How to anchor a boat safely. Types of anchor. Considerations to make when anchoring. Taking transits. How does an anchor work? Retrieving an anchor.

1. ANCHORING
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TYPES OF ANCHOR?
▸ Plough/CQR ▸ Danforth ▸ Bruce ▸ Delta
Assets:
▸ Digs deeper as
pull increases.
▸ Folding
Assets:
▸ Large flukes
provide strong
resistance
against sea bed
Assets:
▸ One piece, no
moving parts.
▸ Good holding
Assets:
▸ One piece, no
moving parts.
▸ Good holding

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TYPES OF ANCHOR?
▸ Grapnell ▸ Fishermans ▸ Mud
Assets:
▸ Folds to small
size
▸ Easy storage
Assets:
▸ Hooks onto rock
▸ Cuts through
kelp & weed
Assets:
▸ Holding power
according to
weigh regardless
of seabed.

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CONSIDERATIONS?
▸ Area
▸ Depth
▸ Wind and Tidal Stream Direction
▸ Safety
▸ Preparation
▸ Crew Briefing
▸ Obstructions

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AREA:
▸ Are you allowed to anchor? - Check a chart,
almanac & local signage to ensure you’re
allowed to anchor at this location you’ve
chosen.
▸ Shelter ? Look for a sheltered area
▸ Swinging room? When the wind/tide changes
direction your vessel will swing, vessels swing
at different speeds so ensure there is plenty
of space between you & other vessels.
▸ Dragging space? You may not get your
anchor set 1st time so ensure there is enough
room to drag, retrieve & reset your anchor.

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SEABED TYPE:
▸ S = Sand
▸ M = Mud
▸ Cy, Cl = Clay
▸ G = Gravel
▸ Co = Coral
▸ Sn = Shingle
▸ P = Pebbles
▸ St = Stones
▸ Rk, Rky = Rock, Rocky
▸ Ch = Chalk
▸ Sh = Shells
▸ Wd = Weed
You can find out the seabed type by looking at a local chart of the
area, you will see the following:

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DEPTH:
▸ What will the tide do during your stay?
▸ Look at the tide heights and times, use chart datum to
calculate the depth of water.
If you don’t do this you could either end up aground or
your anchor may not hold..
(Unsure how to do this? Check out our Tide Tutorials)

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BETWEEN SUNSET AND SUNRISE
Don’t forget to turn on your
anchor light!
AT ANCHOR SHAPES & LIGHTS
During daylight hours,
technically you should show a
black anchor ball.

9. HOW TO ANCHOR?

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SAFETY:
▸ Crew Briefing: Ensure everyone onboard knows their ‘job’
▸ Communications: Set up a system for clear communications
and/or hand signals.
▸ Remember your vessel will drift downwind/tide once the anchor
is laid, so choose a spot upwind/tide to drop your anchor.
▸ Avoid dropping your anchor from the stern as pointing your
vessel stern into the wind / tidal stream may cause the vessel to
be swamped.

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HOW MUCH TO LET OUT?
▸ 4 x the depth = all chain
▸ 6 x the depth (rope + chain)
▸ How to find out depth? Check your chart & tide table OR check
your depth sounder.
▸ If you’re still unsure as to the depth, let out your anchor until it
touches the bottom measuring the amount of chain/warp, then
x it by 4 or x 6 accordingly.
▸ Remember, ‘if in doubt, let it out’ i.e. put out more than you
think!

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HOW AN ANCHOR WORKS:
1. Lays flat on the seabed
2. Vessel drifts back with the
wind/tidal stream or is
motored back slowly
3. Anchor flukes start digging
into seabed
4. Anchor adjust to correct and
angle so flukes ‘wedge’ into
seabed

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HOW TO ANCHOR?
▸ Point your vessel into the strongest
element (wind or tide?)
▸ Stop your vessel
▸ Lower your anchor to the bottom and
ease out the chain/warp using the the
4:1 / 6:1 guidance as it drifts back. If
there is no wind/current then reverse
gently backwards to do this.
▸ Briefly engage reverse to dig the
anchor in if necessary.
** AVOID dropping all the chain /warp
at the same time as it is likely your
anchor will not function correctly.

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CHECK HOLDING:
▸ Identify a transit and
check it at regular
intervals. If the transit is
no longer ‘in-line’ you
are probably dragging!
▸ Set up an anchor drag
function on your GPS/
Chart Plotter
Transits:
▸ Line up two fixed objects
that are in line ideally
from the side of your
vessel so you can track
movement astern.
▸ Take a bearing off a fixed
object (using a hand
bearing compass) this
should remain constant.

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RETRIEVAL:
▸ Check to see how your vessel is lying
▸ If the vessel is pulling back away
from the anchor consider motoring
slowly forward whilst the crew pulls
in the slack and retrieves the anchor.
▸ Good crew communications / hand
signals are essential to avoid running
over the anchor &/or line/chain.
▸ Secure & store your anchor, chain/
warp safely.

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