Doc No: SP0242
Use of Anchors Procedure
Version: 8
Standard Operating Practices
Purpose
Scope
Responsibilities
Master
Chief Officer
Officer in Charge of Anchoring
Procedures
Anchoring Considerations
Anchoring Equipment Design
Scope of the Cable
Nature of the Bottom
Limitations of the Equipment
Anchoring Location
Letting Go the Anchor
Securing the Anchor after anchoring
Deteriorating Weather Conditions
Dragging Anchor
If Loss of Anchor Occurs
Anchoring in an Emergency
When Heaving the Anchor
Securing the Anchor for Sea Passage
Purpose
To outline the procedure when using the vessel s anchors.
Refer to Anchoring-Operational Precautions and Procedures (PT0072).
Scope
This applies to all vessels managed by Teekay Shipping Limited.
Responsibilities
Master
" Ensuring that anchoring of the ship is carried out with due regard to the safety of personnel, the
vessel and the environment.
" Pre planning anchoring operations. Determining a suitable anchorage based on charts, sailing
directions, prevailing and expected weather, navigational warnings, depth of water, nature of
holding ground, expected currents, and proximity of other ships and hazards.
" Holding a  pre anchoring meeting on the bridge explaining to all personnel involved in the use of
anchors the methods to be employed and the safety parameters, and limitations of the
equipment in use.
" Delegating the Chief Officer or designating a deck officer to take charge of the operations
forward. If anchoring conditions are difficult, due to, for example, deep water, strong currents,
rough weather or restricted waters, the Chief Officer must be the officer in charge of party
forward.
" Bunker barge or supply boats shall not be allowed alongside until after completion of anchoring
operations.
UNCONTROLLED DOCUMENT Page 1 of 7
Doc No: SP0242
Use of Anchors Procedure
Version: 8
" The pilot, engines and the anchor party shall not be dismissed until the vessel is confirmed
 brought up to her anchor and is maintaining safe distance from the nearest danger.
" Where the Master is concerned with the safety of the vessel with regards to the proximity of the
other vessels, the depth or the nature of the bottom, then engines should be kept in readiness
on standby or short notice (10 minutes), as appropriate.
Chief Officer
" Ensuring that the anchor and associated equipment are operating efficiently, the brake is
adjusted correctly and the brake band thickness adequate.
" The anchor and cable checked at regular intervals, as far as possible prior to and during each
use, for any defects including defective shackles and loose lugs.
" Lubricating program for the windlass and anchor gear is executed properly and the equipment
maintained in optimum condition.
" Ensuring that the officers and crew forming the anchor party forward are trained properly in
every aspect of the operation.
Officer in charge of anchoring
" Executing the Master s orders during anchoring operations.
" Being aware of the varying capacities of the windlass, including hydraulic motors and anchor
brakes and using them judiciously.
" Advising the Master of the relative direction in which the anchor cable is leading, the weight or
strain on the cable, and any other information, which the officer or the Master may consider
pertinent.
" Ensuring the safety of the personnel involved in anchoring, through the use of appropriate
personal protection equipment. Personnel operating the windlass should wear a face visor /
shield in addition to safety goggles. Refer to Safe Workplace Procedure & PPE (SP0144).
" Ensuring that there are always two seamen operating the windlass brake (the rated force cannot
be applied by one man alone).
" Ensuring that there are two seamen to carry out the final tightening of the windlass brake once
the anchor has been brought up (the rated force cannot be applied by one man alone)
Procedures
" Refer to the publication: List of Shipboard Publications (SP0607) and Anchoring Considerations
(RF0153).
" Plan anchoring well in advance having due regard for:
Available room at the anchorage.
Other vessels at anchor.
Areas to avoid.
UNCONTROLLED DOCUMENT Page 2 of 7
Doc No: SP0242
Use of Anchors Procedure
Version: 8
Prevailing and forecasted weather.
Local tides and currents, their direction and strength.
Water depth and nature of bottom.
Possibility of underwater obstructions
Degree of shelter afforded.
Proximity of land or other dangers.
Length of stay at the anchorage.
Emergency and contingency situations.
Any vessel constraints.
Approach speeds and direction.
Suitable communication with the anchoring party.
Any caution noted on the charts in use.
" Explain in detail, anchoring method, options, limitations of the equipment, and safety parameters
to officers and crew involved. Suitable instructions and guidance should be provided to the
anchoring party. Reference of this pre anchoring meeting should be entered in the logbook.
" Carry out a Job Hazard Analysis or Take Five if required.
" If a pilot is onboard, discuss the anchoring plan as a part of the overall passage plan. The
Master must be in full agreement with the plan.
" Test the main engine in the astern direction, prior to approaching the anchorage.
" Test radio and other communications with the anchor party well in advance. An emergency back
up, such as the vessel s talk back system, should also be tested.
" Avoid anchoring in rough seas or heavy swells.
" Avoid anchoring in or near ice.
" Under normal circumstances the anchor should be walked back under gear to a position just
above the water level prior to letting go on the brake.
" Be aware of the varying capacities of the windlass, including hydraulic motors and anchor
brakes and control their judicious use.
" In deeper waters, e.g. when depths exceed 40 metres, the anchor should be walked back to a
position close to the seabed prior to letting go on the brake.
" Only on occasion and if thought necessary by the Master the anchor may be walked back under
power.
UNCONTROLLED DOCUMENT Page 3 of 7
Doc No: SP0242
Use of Anchors Procedure
Version: 8
" After the required scope of cable has been paid out secure the brake, when possible while the
cable is vertical and without any weight on it, and then secure the cable stopper (pawl /
guillotine).
" Once the vessel is brought up, establish Anchor Watch Procedure (SP0243).
Anchoring considerations
Anchoring equipment design
22
The requirements of the International Association of Classification Societies (IACS) state:
The anchoring equipment & is intended for temporary mooring of a vessel within a harbour or
sheltered area when the vessel is awaiting berth, tide, etc. The equipment is therefore not designed
to hold a ship off fully exposed coasts in rough weather or to stop a ship which is moving or drifting.
An anchor should, therefore, not be expected to hold a ship in rough weather in fully exposed
anchorages. The risks are highlighted by the history of incidents and ships dragging their anchors in
adverse weather.
An anchor provides maximum holding power when its flukes are fully embedded in the sea-bed.
This occurs when the anchor shank lies on the seabed and the anchor cable pulls horizontally at the
anchor shackle. When the pull increases, the cable lying on the seabed is lifted off, creating an
angle above the horizontal. As the angle increases, the holding power reduces.
A rule of thumb is that a pull at 5º above the horizontal reduces the holding power by 25 per cent
and a pull at 15º reduces the power by 50 per cent.
Figure 21: An illustration of a ship at anchor
Scope of the cable
To maximize an anchor s holding power, the scope of cable should be sufficient to ensure that, in
fair weather, a length of cable will lie along the sea-bed and thus pull horizontally at the anchor
shackle. When this occurs, the cable rises gently in a curve to the hawse-pipe. The curve, or
catenary, is necessary to ensure that the cable exerts a horizontal pull on the anchor shackle. This
absorbs any shocks when forces on the ship due to wind, tide and current increase the pull on the
cable. The length of cable, or scope, is key in establishing a catenary.
Most large ships are fitted with about 12 shackles, approximately 330 m, of cable for each anchor.
The common formula for calculating the minimum number of shackles required for calm weather is:
Number of shackles of cable = 1.5 x "depth of water in metres
UNCONTROLLED DOCUMENT Page 4 of 7
Doc No: SP0242
Use of Anchors Procedure
Version: 8
Nature of the bottom
The holding power of an anchor depends to a large extent on the nature of the seabed, or holding
ground. Certain types of mud and clay provide the best holding ground while rock provides the
worst. Seabed conditions must be balanced with other factors, such as the water depth and the
prevailing weather conditions. In strong winds, an anchored ship will yaw and at higher wind speeds
it is increasingly likely to surge rapidly from one extremity of the yaw to the other. This can place a
shock load on the anchor cable, breaking the anchor s hold in the seabed. Increased yawing in
strong winds, therefore, increases the risk of the anchor dragging. An anchor will drag when the
tension in the anchor cable exceeds the total holding power of the anchor and the cable.
Limitations of the equipment
Anchors and associated equipment are intended to work effectively in normal or good conditions.
Therefore, anchor holding power calculations or estimates are not intended to, and should not, be
used to determine the maximum wind speed or weather conditions in which a ship can safely
remain at anchor.
Anchoring location
Anchorage situations with, the close proximity of the coast and other ships, the likelihood of them
dragging anchor if the weather deteriorates, as well as congestion in the anchorage should always
be taken into account. Veering additional anchor cable to ensure sufficient cable is deployed may be
an option in certain conditions. However, attempting to ride out heavy weather at the exposed
anchorage is not recommended by and is not consistent with the practice of good seamanship.
Letting Go the Anchor
" Only in an emergency should the anchor be dropped from its stowed position in the hawse pipe.
" As it is extremely difficult to judge the vessel s movement over the ground, it is recommended
that wherever possible, vessels should avoid walking back the cable after the anchor has
reached the seabed.
" In case the Master decides to walk back the anchor through the entire process the vessel should
be stopped over the ground at the time that the anchor reaches the seabed and thereafter there
should be very minimal way over the ground. Strain on the cable is to be closely monitored. Only
one hydraulic pump should be in operation to prevent over-speeding of the hydraulic motor.
" When anchoring under power keep a close watch on any strain coming on the cable and advise
the Master. Consider ceasing to pay out the cable, secure the windlass brakes and if deemed
necessary remove the windlass from gear till such time as the strain has been relieved.
Thereafter consider paying out on the brakes.
Securing the Anchor after anchoring
" Once the vessel is brought up and excess weight on chain is eased off, apply the anchor
windlass brake fully and lower the stopper bar/guillotine in place and insert securing pin.
" If required to lower the stopper bar/guillotine into place, engage the anchor windlass gear and
adjust the anchor chain position such that stopper bar/guillotine can be lowered in place and
insert the securing pin.
" Apply the anchor windlass brake fully.
" Disengage the anchor windlass from gear.
UNCONTROLLED DOCUMENT Page 5 of 7
Doc No: SP0242
Use of Anchors Procedure
Version: 8
Deteriorating Weather Conditions
" If the weather deteriorates while at anchor, to avoid dragging, damage to cable, windlass,
possible loss of anchor, and the possibility of running into danger, Masters are urged to depart
early from anchorage and proceed to sea until conditions improve sufficiently to enable the ship
to return and re-anchor safely.
Dragging Anchor
" Paying out additional cable should be done in anticipation of anchor dragging, when the anchor
is still holding the ground well. If an anchor has dragged, even if the dragging has been
controlled or ceased, lift up the anchor and anchor again.
" In such circumstances, if deemed necessary, vacate the anchorage.
" Where there is difficulty in getting underway, consider use of the other anchor to prevent the
vessel dragging into danger.
If Loss of Anchor Occurs
" If the vessel is left with only one anchor, do not anchor except in emergencies or in ideal
conditions. Refer to Loss of Anchor or Chain Procedure (SP0284).
Anchoring in an Emergency
" In case the vessel is in anchoring depths and if there is sufficient sea room, consider allowing
the vessel s speed to reduce before anchoring.
" In case anchoring while there is still way on the vessel, consider paying out only sufficient cable
to check the speed of advance and not overcome the effectiveness of the windlass brakes.
When possible, only after the speed has reduced sufficiently should more cable be paid out and
the vessel brought up.
" Always keep in mind the safety of the persons on the forecastle deck.
" If drifting towards danger and required to anchor in excessive depths, consider lowering both
anchors under power to sufficient depths and then securing the brakes, guillotine pawl and other
lashings. Once the vessel moves into anchoring depths, the anchors may help reduce the rate
of drift to that which can then be controlled by the further use of anchors.
" Where possible, main engines should be used in conjunction with the deployment of anchors.
When Heaving the Anchor
" Throughout this operation ensure close communication with the bridge to advise the Master
regarding the lead and strain on the anchor chain and to be able to request the engine
movement to ease the strain on anchor chain and windlass motor in timely fashion
" Check and ease the strain on the cable by use of the vessel s engines.
" Engage the gear, but do not release the windlass brakes till it is apparent that there is no
excessive weight on the cable.
" Use the windlass to heave the cable while keeping a careful check on the strain on the cable.
UNCONTROLLED DOCUMENT Page 6 of 7
Doc No: SP0242
Use of Anchors Procedure
Version: 8
" In case of the possibility of excessive strain coming on to the cable, i.e. if the cable is nipped
across the bow, underfoot, or running well astern; cease heaving the cable, secure the windlass
brakes and if deemed necessary remove the windlass from gear till such time as the strain has
been relieved. Heaving may be resumed once the strain is off the cable.
" If the hydraulic motor stalls during heaving of the anchor, immediately move the control lever to
the pay out direction. Remain aware that moving the control lever to a neutral position does not
relieve high pressure from building up in the hydraulic system.
Securing the Anchor for Sea Passage
" Ensure anchor is fully housed in by observing that both anchor flukes are resting against side
shell.
" Apply anchor windlass brake fully and secure anchor with appropriate wire lashings and
turnbuckles.
" Lower the anchor stopper bar/guillotine in place and insert securing pin.
" After experiencing heavy weather anchor lashing arrangement must be inspected and re-
tightened if required.
" Anchor windlass brake and lashing arrangement are the primary means of securing the anchor
and chain for sea passage. Anchor stopper bar/guillotine and pin are only secondary mean of
securing the anchor and chain. If the anchor stopper bar/guillotine can not be lowered into
position and secured with the pin when anchor is fully housed due to wear on the anchor chain it
should be left in open position and secured.
" Ensuring adequate strength of anchor lashing arrangement which needs to be 2 X the anchor
weight plus 10 metres length of anchor chain. E.g. Anchor weight 17800 kg  Normal stockless
anchor, and 10 metres of grade 3 chain of 102 mm diameter is 2326 kg. Required MBL of the
lashing wire would be:
(2 X 17800 kg) + 2326 kg = 37926 kg or 37.9 tons
This would equate to a steel wire rope of 24 mm diameter and equivalent turnbuckles.
UNCONTROLLED DOCUMENT Page 7 of 7