550 likes | 600 Views
PRACTICAL SEAMANSHIP SAR Crew Manual Chapter 05. DEC 2011. Seamanship. Seamanship is covered by three fundamental principles 1. Order - every to be kept in its place so it can be easily found when required 2. Redundancy - critical systems doubled up - actions and procedures double checked
E N D
Seamanship • Seamanship is covered by three fundamental principles 1. Order - every to be kept in its place so it can be easily found when required 2. Redundancy - critical systems doubled up - actions and procedures double checked 3. Habit - ingraining habits e.g. lines are coiled, closed loop communication is used, and correct helm orders are used
Types of Rope Lay • Cable laid (Left hand) • Hawser laid (Right hand) • Plaited • Braided
Types of Rope Lay • Cable (Left Hand) Laid • In this example three right laid ropes (top) are turned into the cable laid rope (bottom).
Types of Rope Lay • Hawser (right hand) laid
Types of Rope Lay • Plaited
Types of Rope Lay • Braided
Rope Materials • Ropes may be made out of many materials. • Natural fibres - sisal, manilla, hemp, and cotton - not generally used on rescue vessels • Artificial fibres - polypropylene, nylon, polythene, polyester and certain proprietary materials.
Rope Materials • There are other sorts of artificial fibre rope such as Kevlar, Bahamas, Tendon, Kapron, which have their own properties.
Polypropylene • The most common rope in use is polypropylene. It melts at 160 degrees celcius and therefore has the lowest melting point of the artificial fibre ropes. • If you are putting a wet polypropylene rope under tension, if you see rising steam from it, stand back as it could be about to break. • It is light and it floats. • It is susceptible to ultra violet damage.
Line Handling • Line handling is carried out by the crew. This involves: 1. crew safety in their part of the vessel 2. ensure that the docking/undocking plan is clear 3. inspecting lines are in good condition 4. stow away loose gear and coil lines 5. keep colleagues safe by warning of bights and lines under tension
Line Handling 6. keep lines clear of the propeller and warn coxswain when they are not 7. give feedback on progress of operations involving lines
Samson Posts • When making fast a line on a samson post, first make one full turn, before starting belaying the line around the staghorns.
Samson Posts • On turning up on a samson post or tow post, locking tucks are not to be used.
Heaving Line Use • Ensure line’s bitter end is secure to own vessel. • The best way to prepare a heaving line is to make a small diameter (18”) coil. Once enough line has been coiled, split the coil in two, holding half the coil and heaving line knot in the right hand, and the other half of the coil in the left hand.
Heaving Line • Extend both arms to your right, look at where you are throwing. • Swing the heaving line coils anti clockwise and upwards at about 30 degrees, releasing both parts of the coil when on line with the target.
Line Inspection • All lines should be checked regularly along their length for: 1. Broken fibres, cuts, abrasion, unlaying, reduction in diameter, all of which mean a reduction in strength. 2. Powder within the lay which can be a sign of excessive wear. 3. Absorption of oils or chemicals that may adversely affect the rope.
Signs of Overload during Use • Warning signs 1. Groaning, creaking or popping sounds 2. Rotating and/ or stretching 3. Shrinking in diameter 4. Loss of shape 5. Yarns or fibres (and ultimately strands) breaking and peeling 6. Steam rising from a wet rope (polypropylene)
Dangers of Overload • The biggest danger with overload of a artificial fibre lines, where they have a larger capacity for stretching or shock absorbency, when they do break they will return instantly to their unloaded length, causing a severe whip lash. • This can injure an inattentive crew member.
Knots • All good knots should 1. Be easy to tie 2. Be easy to undo after being loaded 3. Be safe when properly used • Knots in ropes will reduce the breaking strain of that rope in way of the knots, by about 50%
Reef Knot Used for joining two ropes of the same size together Not to be used for lines under load
Clove Hitch Perhaps the most widely used of the hitches is the clove, or ratline, hitch. It is especially practical for making a rope fast to a pole or similar object.
Round Turn and Two Half Hitches This is a very useful knot for tying a rope to a post. It can be tied in a rope that is under tension making it useful for boat mooring
Figure of Eight This knot is best when acting as a stopper knot, tied at the end of a line to stop it being pulled through an eye.
Bowline The Bowline is by far one of the best-known and oft used knots. Used to form a fixed loop at the end of a line, the Bowline can be tied with one hand, does not jam and is reasonably secure.
Sheet Bend • The sheet bend is very fast to tie and when slipped, is one of the easiest bends to work with. It is also useful when joining two ropes of different diameters. In this example the red line would be the smaller diameter.
Mooring Lines When one end of the mooring line is made fast on the vessel, and is to be a slip rope, the line is to be passed under the object on the dock before returning on board and making fast.
Cleats Mooring rope should be belayed on a cleat, without use of any locking tuck
The Anchor Shank Fluke Stock Crown
The Anchor • Shank - aids in setting and weighing the anchor • Flukes - dig into the bottom to increase holding power Shank Fluke
The Anchor • Crown - the swivel between flukes and shank • Stock - the part of the anchor to discourage toppling or turning of the anchor Stock Crown
The Anchor • At the top of the anchor shank, there is a swivel and then a length of chain, normally the length of the boat, to which is attached the anchor line. • The chain adds weight to the anchor and also takes the chafing of the sea floor.
The Anchor • Once the chain or rode is shackled to the anchor, the shackle must be moused with a wire to stop the pin coming out.
Anchoring • Anchoring is a process with steps that cannot be skipped. • If you wish to do it right the first time, double check your gear. • The bitter end of the anchor line must be tied to the boat, generally with a weak link - a line of lesser diameter and strength to the rode. • Know the type of sea floor where you are intending to anchor - rocks, sand, or mud.