Anchoring and Ship Handling

Question 1

Anchoring Plan

Answer 1

-Prepare an anchoring plan
-Check weather forecast and wind (onshore wind unsuitable)
-Protection from elements / clffs or topographic feature
-Ensure sufficient depth throughout tidal range
-Passage planapproach track with abort points
-Ensure waypoints for slowing down / stopping
-Use transits / ranges to conspicous object for reference
-Assess type of holding - seabed
-PIs set up
-VRM / EBLs setup
-Conduct proper briefing prior to anchoring
-Report intended anchor position to relevant authorities if required
-Comms tested with anchoring party
-Toolbox talk and risk assessment for anchoring party
-Ensure band brake is firmly attached and then all other secures are removed
-Anchor is lowered and chain paid out to ensure good holding
-PPE used throughout process
-Lights / Shapes shown
-Anchor watch begun
-Any watch orders / night orders updated with relevant parameters.

Question 2

How much chain is required?

Answer 2

ShacklesL 1.5 x square root of depth of water in metres.

or

Chain length 6 to 10 x (depth of water in metres)

Question 3

Health and Safety - Anchoring / Mooring

Answer 3

COSWP Ch 26

-Risk assessment conducted
-Toolbox talk carried out
-Check comms between anchoring party and bridge
-PPE being worn
-Before letting go check under the bow to ensure no obstacles
-Clear away all securing methods
-Lower on windlass

Question 4

Types of anchoring operations

Answer 4

-Single anchor

-Open Moor - two anchors out at almost 180 degrees apart

-Med Moor - two anchors out, stern to dock

-Running / Standing Moor - used if current affects anchoring position. Let go windward anchor (double the final intended amount) and then a Leeward anchor. Then even up on both with a riding anchor taking the weight and a sleeping anchor ready for the tide to turn.
Difference between running and standing is use of engine.

-Snub around - dropping anchor (to increase drag, not on the sea bottom) to turn in a tight space or when danger ahead.

-Offshore anchor - used to pull vessel off dock with offshore anchor

Question 5

Anchor fouled on Submarine cable

Answer 5

-Confirm cable on chart / mark on chart
-Lower anchor back down / taking photo first
-Disconnect anchor at lugless joining shackle (Kenter shackle)
-Bouy anchor
-Contact relevant authorities to report anchor fouled on submarine cable and continue operating with one anchor (Flag, Port State, Port Authority)
-Dispensation required due to sailing with one anchor

Question 6

Turning short round

Single Right hand prop

Answer 6

(Transverse thrust)
-Helm order hard to starboard and apply power
-Stop engine / helm to midship
-Full astern to bring stern around via transverse thrust
-Engine ahead and helm to starboard
-Bow now around and turned short around

Question 7

Berthing

Single Right hand prop

Answer 7

Toolbox talk and Risk assessment prior to doing any berthing/unberthing

Port side too
-45 degree approach to dock
-Bow near dock
-Astern to bring stern towards dock

STBD too
-Come fine to dock (15 degrees)
-Prior to coming alongside apply a small amount of port helm
-Vessel brought alongside

Question 8

Manoeuvring Information
(MGN301)

Answer 8

Pilot Card - intended to provide information to the pilot on boarding the ship. Should describe current condition of the ship with regard to loading, propulsions

Wheelhouse poster - permanently displayed in the wheelhouse - contains general particulars and detail information regarding manoeuvring characteristics. Steering particulars, anchor chain length, propulsion particulars (RPM/Speeds), thurst power, turning circles, stopping characteristics.

Once at sea - confirm manoeuvring characteristics

Question 9

Interaction (MGN199)

Answer 9

Squat: A reduction in the UKC due to Bernoulli Principle and the suction of the vessel in depths of water of up to twice the draft. It is not an increase in draft. Only occurs at speed so reduction in speed best action!

Occurs in reduced depth forcing the water to move faster under the hull to the increased resistance. Increase in velocity results in a low pressure. (Bernoulli Principle)

Formula for various depths UKC. SpeedxCB/Depth under keel

-Hydrodynamic interaction continues to be a major contributory factor in marine incidents.
-Shallow water (any depth less than twice the draught - 10m if draught 5m)
-Ships turning radius increases in shallow water
-Trim changes

Interaction within channels
Bank effect
-bank sheer (pushing away)
-bank suction
-OOCL Finland and general cargo vessel Tyumen-2

Reduction in speed is the only way to reduce the effect of squat in shallow water.