AUXSEA Chapter 9 Anchoring

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SEAMANSHIP CH. 9 ANCHORING
The study references for this chapter are again
found in Chapmans Piloting, Seamanship and Small
Boat Handling, along with this Power Point
Presentation and the USCG Auxiliary Student
study guide and practice questions.
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ANCHORING QUESTIONS TO CONSIDER

• The process of anchoring is mostly a combination
  of a SEAMANS EYE and common sense.
• What do you want the anchor to do?
• How big an anchor do you need?
• Where will you be anchoring?
• Where will you keep it on the boat?
• Who will handle the anchor

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WHAT DO YOU WANT THE ANCHOR TO DO?

• You want the anchor to HOLD THE BOAT WHERE YOU
  PUT IT.
• That implies that the anchor must STAY where you
  PUT it.
• It must be light enough to comfortably handle and
  yet heavy enough to dig in and hold the bottom.
• It must be designed for the bottom types you will
  encounter the most.
• It must hold in all kinds of weather, seas and
  current.

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HOW BIG AN ANCHOR DO YOU NEED?

• A mistaken concept is that the effectiveness of
  anchor depends upon the weight, for its holding
  power. For most Auxiliary vessels ( 16-26 ft.) a
  utility type 12-18 lb. type is satisfactory.
  Deeper draft vessels may need a little more.
• The anchors holding power depends on the design.
• There are anchors designed for every type of
  bottom known. Try to choose the anchor for your
  vessels weight, handling characteristics, use
  and area of operation bottom type.
• They are made from aluminum, steel, cast iron and
  bronze, depending on the desired use.

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DESIGN

• The primary motivation for the design of an
  anchor, is its HOLDING POWER.
• Most of the characteristics of the anchor reflect
  its ability to DIG IN and continue to hold,
  without turning over, flipping, or simply
  breaking loose.
• Additional considerations are its ability NOT to
  foul on anything it may encounter.
• Finally, the ease of maintenance feature must be
  considered.

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WHERE WILL YOU BE ANCHORING

• Bottom type is probably the greatest item of
  consideration for the TYPE of anchor you will
  need. Consult your navigation chart in your
  operating area. Its printed right on it.
• Lightweight anchors such as the Danforth-type by
  Danforth or Fortress, the Plow, the Delta, the
  Bruce, the Max, the Kedge, the Navy-type and the
  Grapnels, Folding types, and the Northill and
  Mushroom type are either general purpose or
  designed for a limited range of specific uses.
• Bottom - types such as hard, rocky, gravel,
  sand, mud, grass or coral are often found in
  combination and must be taken into consideration
  for true successful anchoring.

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STORING THE ANCHOR

• It and all other accompanying gear such as the
  rode, should be stored in a location FOR
  IMMEDIATE USE mode.
• It should remain free of all entanglements or any
  fouling apparatus.
• There should be ample room for the rode to run
  free.

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WHO WILL HANDLE THE ANCHOR?

• Do not buy an anchor that cannot be comfortably
  handled by your crew. It will not be a satisfying
  experience.
• Consideration should be given to the physical
  capabilities of the crew including their
  eyesight, hearing capabilities, their
  limitations, training and knowledge of the
  functions and importance of ANCHORING.

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ANCHOR TYPES
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MORE ANCHOR TYPES NOMENCLATURE
Flukes
Shank
Ring or Jews Harp
Bill or Pea
Arm or Tripping Palm
Crown
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YACHTSMANS ANCHOR

• Almost a generic name for a number of different
  styles, all lightweight and designed for average
  holding power. Easy to handle and reliable.
• The stock enables the anchor to remain orientated
  so as to maintain its maximum holding power, as
  long as this is not broken by the incorrect
  tension on the rode raising the shank to too high
  an angle.
• Somewhat antiquated in design now but still an
  efficient anchor.

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SAMPLE ANCHOR TYPES

• Most anchors do rather poorly in GRASS.
• FORTRESS anchors can be assembled in two ways to
  enable them to increase their efficiency. They
  have great holding power and are of lightweight
  aluminum.
• The DANFORTH itself is the popular choice. Made
  from aluminum or steel. Great holding power.
  Excellent balance.
• The PLOW ( or CQR) Excellent on wide range of
  bottom conditions.
• The BRUCE anchor Developed for offshore oil rigs
  it has been scaled down for small boats.

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SPECIALIZED TYPES

• The KEDGE
• NAVY TYPE
• GRAPNELS
• FOLDING TYPES
• THE NORTHILL
• MUSHROOM TYPE

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THE KEDGE, NAVY AND GRAPNELS
KEDGE types The Hereshoff, Fisherman and the
Yachtsman. All Excellent on heavy grass or weed
bottoms. Also commonly used to kedge a grounded
boat off the bar. NAVY types Not the best for
small boats. They must weigh far too much before
their holding power becomes efficient. Used on
big ships because they are flukeless so as to be
retrieved into hawse pipes. GRAPNELS Not
recommended for small boats. Good in rocks. Must
use a tripping line to free them otherwise, you
are permanently attached to the bottom!
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ADDITIONAL TYPES

• FOLDING TYPES Some sacrifice to holding power
  and strength. Good on rocks and also on grass and
  weeds when properly rigged. Not too good in soft
  sand or mud.
• The NORTHILL Excellent for stowage. Made from
  stainless steel. Again, it is a foldable similar
  to the grapnel in appearance.
• MUSHROOM type The smaller weights are very
  popular for very small boats, dinghy's, canoes,
  etc. . The larger sizes are popular for permanent
  moorings, holding huge vessels in the thousands
  of tons.

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TWISTED THREE STRAND NYLON

• All of the gear, collectively, between the anchor
  and the boat, is called the ANCHOR RODE,
  whether it is of chain, synthetic fiber or a
  combination of both.
• The most widely used material for the anchor line
  is three-strand twisted or double braided nylon.
  Chain makes a good rode but the weight is
  generally prohibitive.
• DOUBLE-BRAIDED NYLON is elastic. The stretch
  qualities (15-25) make it ideal for stress
  loads in heavy seas while at anchor. Stow it out
  of the direct sunlight!

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BRAIDED SYNTHETIC LINE

• DOUBLE BRAIDED NYLON Gives exceptional stability
  without the twisting characteristic of the
  twisted variety. No kinks. Can be easily faired
  through fittings and into storage. You need to
  fake it down to prevent a set.
• It is less subject to chafing, but is slightly
  less elastic ( only about
• 14 , compared to twisted nylon ).

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CHAIN

• CHAIN is for vessels which would require too
  large a diameter of nylon for an efficient anchor
  line. It can be used, however, as a personal
  choice.
• In heavy coral or rock areas, chain is ideal and
  in some cases, indispensable to reduce or
  eliminate excessively heavy chafing.
• BBB, PROOF COIL and HIGH TEST CHAIN( the best )
  The three kinds of chain most commonly used as
  anchor chain.
• CHAIN must be matched to the wildcat used to
  hoist and lower it.
• IDEAL COMBINATION Nylon ,with 6-8 ft. or longer
  length of chain. Chain helps to keep angle of
  stock very low to bottom for max dig power of
  flukes.

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ANCHORLINE HARDWAREEYESPLICE THIMBLE - SHACKLE
PREFERRED METHOD to bend the anchor line to the
anchor is to thread a shackle through the eye of
the shaft and secure the shackle bolt through
the end link of chain. On the other end of the
chain, another shackle but this time, secure the
shackle pin through a THIMBLE , which has been
worked into an EYESPLICE in the end of the anchor
line, to prevent chafing. Safety wire the shackle
pins to prevent them from turning out. OTHER
FASTENINGS The bowline or the anchor bend or any
other acceptable knot may be used but care should
be taken to use one which can be broken down
easily.
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CLEATS, SAMPSON POSTS, BITTS, CHOCKS, ETC.
ALL FITTINGS Should be through-bolted and backed
up with steel plates, to reduce the possibility
of a strain on the anchor line which has been
secured to this hardware, pulling the bolts back
through the deck or anchoring surface. REMEMBER
It is the objective of the anchoring maneuver, to
keep the boats position stationary. If the
fittings pull out and the anchor runs free or
drags as a result, the failure of the fitting may
jeopardize the vessels safety.
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SCOPE

• DEFINITION The length of the anchor rode in
  relation to the height of the bow above the
  bottom of the water body ( R Bh ) where R Rode
  length and Bh Bow Height of the bow above the
  water.
• Interpretation and application The length of
  the rode.
• You know you should have a minimum scope of 5
  1 but should have 7 1 in fair weather. You have
  80 ft. of rode out in 10 ft. of water which gives
  you a scope of 81 (80 10).
• However, if your bow is 3 ft. above the water
  your actual scope is only (80 13
  approximately a little more than 6!
• The SCOPE is a MAJOR FACTOR that determines
  whether you will DRAG or HOLD!!

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ANCHORING FAVORABLE CONDITIONS
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MARKING A LINE FOR SCOPE

• One of the marks of a professional seaman are the
  little plastic tabs with depth numbers on them,
  which have been inserted between the strands of
  anchor and towing lines, especially but also for
  any other line where LENGTH is a key factor.
• Plastic CABLE MARKERS are inexpensive, permanent,
  easy to apply and take the guesswork out of
  length requirements altogether.
• They also display a distinctive character
  attribute of the owner a desire to do it right.

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PERMANENT MOORING
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SELECTING THE ANCHORAGE
1. ALWAYS USE YOUR CHART to pick your anchorage.
Its your road map to the area, in detail. 2.
Try to pick a bottom that has little or no mud,
loose sand or heavy grass, for better holding
characteristics for the anchor. 3. Try to anchor
with your bow into wind. This will help to keep
your sleeping area free of insects living on the
surrounding land mass. It also will help in
getting underway as you are already heading out
and you do not have to turn around! 4. Try to
pick an orientation which will give you as much
lee as possible, in case of inclement weather.
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APPROACHING THE ANCHORAGE

• Keep in mind, if you use only one anchor, you are
  free to rotate 360 degrees on your anchor during
  the night or day, possibly over dangerous rocks
  below or into other anchored boats in the
  anchorage. Keep this in mind in choosing the
  spot and when approaching.
• Use your GPS or suitable range marks you have
  chosen, to navigate to the desired spot to drop
  the anchor.
• Visualize other vessels already anchored and how
  they might swing or set up in any current or
  wind, before your final selection of a good spot.

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LETTING GO THE ANCHOR

• THINGS TO CONSIDER
• BOATS MOTION
• LOWERING THE ANCHOR
• SETTING THE ANCHOR
• DRAGGING ANCHOR
• DECK FASTENERS

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LETTING GO THE ANCHOR

• As a good sailor, your anchor and all the
  necessary gear is ready.That means it is
  properly and adequately attached with secure
  fittings, backed, and the deck is cleared for
  working.
• STOP ALL HEADWAY. Reverse you engine at idle
  speed. Just as you begin noticeable sternway,
  lower the anchor slowly but positively until it
  hits the bottom on the crown.
• The goal is to PREVENT fouling.

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SETTING THE ANCHOR

• An anchor MUST be SET to yield its FULL HOLDING
  POWER.
• This is somewhat trial and error because every
  boat is different.
• Pay out the rode until you get to your
  pre-selected marker. Take a turn or two around a
  cleat. Check things out to see if it is holding.
• Keep doing this until you are satisfied it is
  holding.
• When you are satisfied, stop the rode with
  whatever system you have.
• Pick out at least two ranges, one on each side at
  about 45 degree angles to each other and make a
  note. Your anchor watch can detect drift by
  these sightings later and take corrective action..

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WHEN THE ANCHOR DRAGS

• Check the bearings of the two ranges you chose
  when you came into the anchorage.
• Be prepared to get underway immediately and to
  fend off, if necessary.
• If there is no immediate danger of collision and
  you have enough room, let out additional scope
  and test for holding each time.
• On the engine, bring the bow back into the wind
  to ease the strain on the rode.
• If it is reasonable, raise the anchor to clear
  any fouling that might have taken place.

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INCREASING THE HOLDING POWER

• SENTINEL A weighted device you can slide down
  the rode, with an attached tether line to
  control how far down on the rode you want it.
• This device sets a sag in the rode which
  reduces the angle between the rode and the
  bottom, making the anchor flukes dig in better
  making it more difficult to pull out thus
  increasing its holding power.
• A length of heavy anchor chain will work good
  also to achieve the same result.
• An anchor buoy set midway between the bow and the
  anchor will also help to relieve the strain on
  the anchor in heavy seas, and reduce the threat
  of pulling the anchor out.
• You can combine the buoy, chain and sentinel if
  necessary.

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CLEARING A FOULED ANCHOR

• Best method is to rig the anchor with a BUOYED
  TRIP LINE, secured to a ring on the crown and
  attached to a cleat on the boat, BEFORE YOU LOWER
  IT. Retrieving this line will break the anchor
  lose and you can pull it in backwards, further
  helping to wash grass or mud from it, or breaking
  it out from rocks.
• Try running a heavy length of chain down the
  rode, with a line attached to it. From another
  boat or dinghy, from 180 degrees to your rode,
  pull your anchor loose.
• If the anchor is deep in heavy clay, wait until
  low water shorten up on the rose as tight as you
  can get it and wait for rising water to do the
  job.

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GETTING UNDERWAY

• ALWAYS have your mainsail up and set or your
  engine on and in gear, for positive control,
  before breaking the loose from the bottom.
• Setting in a current, near shore, grass and other
  like debris will entangle in the anchor rode.
• Whipping the line up and down in a snapping
  motion will help clear most all of it.
• Do not store the anchor line with any of this
  debris as it will hasten its breakdown and
  carries this moisture down below decks where it
  is most undesirable.
• KEEP THE ANCHOR OFF OF THE HULL!

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USING TWO ANCHORS

• Use of two anchors, a working anchor and a
  storm anchor, will help to correct for
  deficiencies with only one anchor, when in heavy
  weather. The STORM anchor can be run out and set
  without moving the working anchor at all.
• A careful watch must be kept on the lines to see
  that they do not become fouled and pull each
  other loose from the bottom. Cleat each rode
  separately to different sides of the boat.
• Deep draft sailboats will lie head into the wind
  naturally. Power boats and small skiffs tend to
  put their sterns into the wind, if left alone. It
  may become necessary to use two anchors with
  these vessels to keep them out of trouble.

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USING TWO ANCHORS CONTd

• 5. Allow for clearing the swing with other
  obstructions.
• When anchoring in a tidal or current way, where
  you know either will change 180 degrees during
  the anchorage, set two anchors at 180 degrees to
  each other, with the bow at the midpoint of the
  two rodes.
• 6. Two anchors are a must if you wish to
  orientate your boat in a fixed position.
• 7. Never dock on the weather side. Considerable
  damage is possible.
• 8. Stand off and set two anchors on the outside,
  to hold you off the weather side of the pier, if
  practical.

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RAFTING TO ONE ANCHOR

• Do not raft to a single anchor in other then very
  light current or calm wind conditions. Otherwise,
  one or more of the other boats will cause the
  single anchor to break loose and ALL will drift.
• Instead of rafting to the other boats anchor,
  raft to other boat with your regular docking
  lines. They are easier and quicker to break away
  with.
• For SAILBOATS, make certain all rigging,
  especially aloft, stays clear when rafting.
• DO NOT leave boats rafted for the night. Each
  boat should seek their own anchorage for the
  night.

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ANCHORING AT NIGHT

• To check for drift at night, you can set your
  leadline with a little slack. If it becomes taut,
  you have drifted and your anchor is dragging.
• Dont forget to pick it up when leaving in the
  morning!
• Dont forget your ANCHOR LIGHT to meet your
  boats requirements of the Rules.
• In addition, during the day, if you are required
  to meet the rule, your SINGLE BLACK BALL dayshape
  should be flying from your crows nest.

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ULTRAVIOLET

• At the cost of lines today, you will not need too
  many reminders of this, but DO NOT LEAVE YOUR
  LINES, ANY OF THEM, EXPOSED TO THE SUNS
  ULTRAVIOLET RADIATION ANY LONGER THAN ABSOLUTELY
  NECESSARY.
• If the line must be left on deck, shade it.
• Dry them, if practical, and store them in a cool,
  dry place, preferably your rope locker.
• Remember FLEMISH it. FAKE it or COIL it. DO NOT
  CHORD IT ( gather it into a lump and throw it in
  a box!)!

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REVIEW QUESTIONS NO. 1

• The most widely used material for the anchor line
  is_________
• a. polypropylene
• b. polystyrene
• c. nylon
• d. rayon

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REVIEW QUESTYIONS

• The most widely used material for the anchor line
  is__________
• c. nylon

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REVIEW QUESTIONS NO. 2
2. All gear, taken collectively, that lies
between the boat and its anchor is called the
_________. a. line b. mooring c. rode d. cast
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REVIEW QUESTIONS
2. All the gear, taken collectively, that lies
between the boat its anchor is called the
____________ c. rode
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REVIEW QUESTIONS N O. 3
3. The lightweight type anchor is excellent on
______ and sand bottoms. a. rock b.hard c.
gravel d. mud
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REVIEW QUESTIONS
3. The lightweight anchor is excellent in _____
and sand bottoms. d. mud
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REVIEW QUESTIONS NO. 4
4. Chain is designated by the __________ of the
material in the links. a. length b. weight c.
metal d. diameter
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REVIEW QUESTIONS
4. Chain is designated by the _______ of the
material in the links. d. diameter
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REVIEW QUESTIONS NO. 5
5. The ideal rode for most average conditions is
a combination of _________ and a short length,
less than 1 fathom of chain. a. cable b.
nylon c. rayon d. polypropylene
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REVIEW QUESTIONS
5. The ideal rode for most average conditions is
a combination of ____ and a short length, less
than 1 fathom of chain. b. nylon
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REVIEW QUESTIONS NO. 6
6. When anchoring under favorable weather and sea
conditions and using nylon line, a scope of
________ might be considered a minimum. a. 5
3 b. 4 8 c. 5 1 d. 5 1
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REVIEW QUESTIONS
6. When anchoring under favorable weather and sea
conditions and using nylon line, a scope of
_________ might be considered a minimum. d. 5
1
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REVIEW QUESTIONS NO. 7
7. When anchoring, the anchor should _____ be
lowered when the boat has any way on. a.
always b. never c. probably d. must
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REVIEW QUESTIONS
7. When anchoring, the anchor should____ be
lowered when the boat has any way on. b.
never
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REVIEW QUESTIONS NO. 8
8. If an anchor drags, the first step in trying
to get it to hold is to_______. a. pay out more
scope b. take in scope c. change anchor
size d. try another spot
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REVIEW QUESTIONS
8. If an anchor drags, the first step in trying
to get it to hold is to_____. a. pay out more
scope
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REVIEW QUESTIONS NO. 9
9. When chocks, cleats and other fittings are
used on deck, they must be _________ and
reinforced with a strong backing plate. a.
heavily screwed b. through-bolted c.
screwed d. stopped
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REVIEW QUESTIONS
9. When chocks, cleats and other fittings are
used on deck, they must be _________ and
reinforced with a strong backing plate. b.
through-bolted
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REVIEW QUESTIONS NO. 10
10. The type of anchor traditionally used for
permanent moorings is the _______. a. pan b.
mushroom c. folding d. navy
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REVIEW QUESTIONS
10. The type of anchor traditionally used for
permanent moorings is the ________ b.
mushroom
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END CHAPTER 9