Ship handling – Single Screw RH Propeller

Pivot Control

If a vessel deploys a single anchor on the offshore side a fulcrum can be achieved which gives the engine and helm something to work against. As mooring ropes are deployed the ship can be brought alongside in a controlled manner in quite strong wind and tide conditions. This is a prudent methodology where availability of thrusters or tugs may be in question, as it will expedite unbirthing.
This will assist in tidal waters when unsure if you will depart on ebb or flood. A well placed anchor and three shackles of cable will act as efficiently as a bow thrust or harbor tug.

Baltic Moor

The Baltic Moor allows a larger yacht to lay against a jetty which may be of uncertain construction. The stresses on the jetty are reduced in an onshore wind by the anchor and checking warp. This method also ensures that the vessel can clear the jetty safely on departure. Few yachts carry wire ropes so a suitable (nylon) rope of good strength should be selected. The rope is passed from aft on the off shore side and carried forward, outside of all obstructions, with sufficient slack for the eye or end of the rope to be shackled onto the ‘D shackle’ of the offshore anchor. Ensure that there is sufficient rope flaked on deck to reach the sea bed when the anchor is let go.

When the stem of the vessel is in transit with the mid point of the berth, let go the anchor and its attached checking warp. Great care must be taken by the officer aft to ensure that the warp does not snag on the propeller.
The vessel is allowed to drift in the wind using engine and helm to assist, ensure an even weight on both cable and warp. Both are paid out together.
As the vessel comes alongside weight must be maintained on cable and warp and mooring ropes should not be over stressed.

The Mediterranean Moor

The most common method of yachts mooring in the Mediterranean is with the use of ground lines. This has the advantage of preventing the fouling of anchors. Where these groundlines are not available the Mediterranean moor, from which the idea derived still has value. The Mediterranean moor uses both anchors, it allows berthing stern to quay and it is important that the anchors are kept apart for protection against fouling and also to reduce the scope of the bow in any wind condition. The available sea room will determine where these anchors can be placed and the mariner should consider marking them with a buoy to deter other vessels fouling your anchor. Prevailing wind conditions will determine the line and speed of approach which should be head to wind. The anchors need to dropped half a ships length apart when the vessel is two ships length from the quay.

When running parallel to the jetty, two ships length off, drop the offshore anchor.
After running for half a ships length forward take all way off the vessel.
As the bow cants (to starboard) drop the on shore anchor.
By backing and filling position the vessel between the two anchors.
Position the ship with stern lines and adjust anchor cables to suit.

This type of mooring requires skill and practice if wind is parallel to the line of the jetty but is effective during on shore or off shore winds.

Berthing – Wind Onshore

Angle of approach to the berth will depend on trim windage and freeboard.

Select an appropriate transit, this will help to monitor drift and enable adjustment of engine accordingly. Dredge offshore anchor initially to keep the head off shore.
Pay out more cable as the vessel progresses but maintain the transit. Use kicks ahead and port helm to control vessel.
Allow the ship to land on the jetty parallel by controlling anchor forward and helm/engines aft. Double up on fwd back spring if using this against engines. In strong wind conditions both anchors may be used if kept apart, drop the onshore anchor at 2 and dredge. (There is risk of paint damage here) Make fast after spring asap when alongside.

Berthing – Wind Offshore

Decide on angle of approach to suit windage, trim and freeboard.

Select good transits to monitor approach. Let go offshore anchor enough to dredge towards berth.
Use engine and rudder to prevent bow from falling off wind Have a strong messenger and stern rope ready at the shoulder for running ashore as soon as possible.
Stb helm and Half ahead. Run stern line ashore. When bow is fast ashore swing stern towards jetty using engines and rudder, until weight is transferred to stern rope. Finally heave ship alongside, slacking anchor cable as necessary. In very strong winds kedging two anchors gives good control until ropes are fast ashore.

Berthing – Stern to Tide

This is one example of many. This does however require adept bow crew who can use the anchor. Care must be taken of fouling the anchor.

Approach the berth at a shallow angle, stemming the tide. Pass out two good stern ropes from the offshore quarter leads. Allow the bow to fall off with the tide.
Let go port anchor. When the weight is taken by the stern ropes, and then if it does not swing weigh the port anchor and drop again as needed.
Control the swing of the vessel onshore by use of the anchor. Carry head ropes aft and pass ashore if the bow is out of heaving line range. The final position for the anchor should enable this to be used in an onshore wind departure.

River Dock Entry

This is a complex manoeuvrer and requires preparation. There is a potential to need very long mooring ropes or couple two together.

Fenders will be required and should be pre rigged on the strake/dock rubbing line.
With fenders rigged manoeuvrer alongside quay using ferry glide method and a transit.
Make fast to the quay, your backspring may be doubled.. Now run a long headline to a bit beyond the knuckle. Run another headline from the centre fairlead to the opposite dock wall. Run a single backspring from aft to the nearest knuckle.
As you move forward let go of the short back spring and take up the slack on the centre fairlead headline. Beware that as the vessel is warped around the knuckle whilst the bow is in slack water the stern will still be set down by the tide.
You are now on the dock wall and may be berthed. If you are required to berth on the upstream dock wall then stern rope must be passed from the bow at position 4 and headline will need to be rigged from the stb shoulder.

Unberthing – Onshore Wind

Transfer the forward spring as far forward as possible. Consider doubling the spring. Then single up. Take the headline from the outboard side on a short stay. Rig large fenders at the stem on shore side at a height to match the quay.

Let go the stern ropes, when the propeller is clear heave on the headline until the fwd backspring is taught.
With the stern heaved out as far as possible, helm hard to port and kick ahead the engines.
Let go all ropes and then engines full astern.
With good stern way the vessel pivot point moved above the rudder stock and the vessel will seek the wind. Maintain sternway until clear of the quay. This should not be attempted in a strong wind without the aid of a tug or bow thrust.

Unberthing – Stemming the Tide

Single up to 1 spring and one line each end. Transfer the after spring to the quarter lead.
Let go fwd ropes and let bow come off the jetty release the slack stern line but hold the back spring.
Release spring and wait for lines to be clear.
Kick ahead.
Helm to starboard and clear quay. If the vessel is stern to tide do the same manoeuvrer but fender the bow to prevent damage when the stern comes clear. In all cases a kick on the engine will usually start the process.

Turning Short Round – Head to Wind/Tide

Vessel moves to the left hand side of the channel where the rate of the current will be less.
Starboard helm is applied canting the bow into the faster flowing centre channel.
Vessel engages astern propulsion to keep bow in the faster flowing water.
Full starboard helm and ahead movement completes the manoeuvrer Transverse thrust will act on the stern at 2 because it is in calmer water than the bow. In a strong wind take all way off the ship before attempting the starboard swing across the wind. This will take full advantage of the pivot point movement.

Turning Short Round – Stern to Wind/Tide

With wind/tide astern. The vessel moves from the starboard side of the channel into a central point of a river.

Engines stopped and full starboard helm applied.
With tidal stream now on the side of the vessel – Amidships helm and Full astern to take the headway off the ship. When the vessel gains a slight sternway the helm again to starboard engines full ahead to pivot on the centre line.
Engines astern and helm to port to assist turn. When wash reaches amidships, helm full to starboard and full ahead to turn.
Vessel is now turned but on the left side of the river.

This manoeuvrer uses the transverse thrust of a right-handed propeller when going astern which thrusts the stern to port. If tidal stream is very strong or when running before the wind it is prudent to use the starboard anchor to ‘snub round’ and reduce drift. Trim, freeboard, list and draught in relation to available depth of water will all vary the tactical turn. With restricted swinging room it is advisable to make use of the starboard anchor. When any vessel is moving astern it will seek the wind astern as the pivot point moves aft. This can be reduced by ensuring the engines are stopped as the backwash reaches the conning position.

Running Moor

A running moor uses two anchors to reduce the scope of the anchor when tides change from ebb to flood. In this case vessel is approaching on the ebb. A final anchor position must be selected and number of cables determined. This must not be more than half your available anchor chain. Both anchors must be lain in line with the ebb/flood tide direction. A helpful transit bearing should be identified.

Drop anchor. Run double the intended length of anchor chain out as vessel runs forward. Proceed into tidal flow at slow speed.
As weight comes onto the chain drop the port anchor.
Take up weight on starboard anchor and pay off the port anchor. Adjust length of anchor chain to suit desired transit position.
Ship should only be allowed to swing at tide changes between position 3 & 4.

If the ship swings inshore of the anchor position the hawse will foul. This can be controlled by use of helm or helm and engine at tidal changes.

Standing Moor

A standing moor uses two anchors to reduce the scope of the anchor when tides change from ebb to flood. In this case vessel is approaching on the ebb.
A final anchor position must be selected and number of cables determined. This must not be more than half your available anchor chain. Both anchors must be laid in line with the ebb/flood tide direction. A helpful transit bearing should be identified.

Pass the transit position, head to tide. Drop anchor then drift astern. Run double the intended length of anchor chain out as vessel drops astern.
Hold onto the port anchor when astern of the transit and on the second anchor position.
Take up weight on port anchor and pay off the starboard anchor as you run ahead. Adjust length of anchor chain to suit desired transit position.
Ship should only be allowed to swing at tide changes between position 3 & 4.

If the ship swings inshore of the anchor position the hawse will foul. This can be controlled by use of helm or helm and engine at tidal changes.

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