Thursday, September 25, 2014

SEAMANSHIP



Seamanship- is the art of operating a ship or boat.
It involves topics and development of specialized skills including: navigation and international maritime law; weather, meteorology and forecasting; watch standing; ship-handling and small boat handling; operation of deck equipment, anchors and cables; rope work and line handling; communications; sailing; engines; execution of evolutions such as towing; cargo handling equipment, dangerous cargoes and cargo storage; dealing with emergencies; survival at sea and search and rescue; and fire fighting.
The degree of knowledge needed within these areas is dependent upon the nature of the work and the type of vessel employed by a mariner.

Navigation- Navigation is the art and science of safely and efficiently directing the movements of a vessel from one point to another. Piloting uses water depth and visible references, while dead reckoning uses courses and distances from the last known position.[1] More than just finding a vessel's present location, safe navigation includes predicting future location, route planning and collision avoidance. Nautical navigation in western nations, like air navigation, is based on the nautical mile. Navigation also includes electronic such as GPS and Loran(Long Range Navigation). Celestial Navigation, taking sights by sextant on the planets, moon, stars, sun and using the data with a Nautical Almanac and sight reduction Tables to determine positions. Accurate time information is also needed.

Ship-Handling- A fundamental skill of professional seamanship is being able to maneuver a re’p/;77r5’

Ship-handling is about arriving and departing a berth or buoy, maneuvering in confined channels and harbours and in proximity to other ships, whilst at all times navigating safely. Two other types of operations, berthing alongside another ship and replenishment at sea, are occasionally included. A key ability for a ship-handler is a good understanding of how the wind, tide and swell, the passage of other vessels, as well as the shape of the seabed, will affect a vessel's movement, which, together with an understanding of a specific vessel's performance, should allow that vessel a safe passage.




Fundamental to low-speed maneuvering is an understanding of the configuration and handedness of the propeller(s). An effect known aspropeller walk will kick the stern of the vessel to port or starboard depending on the configuration and the type of propeller when large variations on propeller rotation speed or changes of propeller rotation direction take place. (In single-screw vessels where the rotation of the propeller is reversed on an astern bell, a standard was established that the propeller would turn clockwise when viewed from astern. This would mean that the propeller would turn counterclockwise when going astern and the stern would walk to port. This aided in docking operations, where "port side to" was the preferred situation and the vessel would be brought to the dock with a small bow-in angle and backing would flatten the angle, slow or stop the vessel and walk it alongside. An exception to this was the U.S. Sealift class tankers, which used a controllable pitch propeller, where the pitch and not the direction of rotation was reversed to go astern. These propellers rotated counterclockwise at all times and so the "walk" was "normal".) Other variations include what are known as bucket rudders such as the Kortz Nozzle where instead of a conventional rudder a pair of dish-shaped rudders, one either side of the propeller can be swivelled vertically to direct the propeller thrust through 360 degrees.

 Thus to put the vessel into astern mode the rudder can be rotated through 180 degrees without altering the speed and direction of the engine. Since with the conventional propeller or rudder configuration the propeller is designed to operate at maximum efficiency when going ahead, it produces far less thrust when going astern. But with the Kortz Nozzle, the ahead and astern thrust is the same. Other advantages of the nozzle are the ship can be steered astern which a conventional rudder cannot, and the ship can be steered fully under control to a standstill switching between ahead and astern mode to give complete control over speed. In addition to being fully conversant with the principles of seamanship and ship-handling, a good pilot will have developed his or her sense of 'situational awareness' to a point well beyond that of a member of a ship's crew; his reactions will appear to be instinctive, positive and at all times safe.
Most commercial vessels in excess of size limits determined by local authorities are handled in confined areas by a marine (or maritime) pilot.





 Marine pilots are seafarers with extensive seafaring experience and are usually qualified master mariners who have been trained as expert ship-handlers. These pilots are conversant with all types of vessel and propulsion systems, as well as handling ships of all sizes in all weather and tidal conditions. They are also experts in the geographical areas they work.

 In most countries, the pilot takes over the 'conduct' of the navigation from the ship master. This means that the master and crew should adhere to the pilot's orders in respect of the safe navigation of the vessel when in a compulsory pilotage area.

The master may with good cause resume 'conduct' of the vessel's navigation. However this should never be done lightly. In situations where the pilot is an "advisor" even though he has the con, the pilot or his "Association" have no responsibility or liability in the case of an accident. The master, upon realizing there is a dangerous situation developing, must take such action as to avoid an accident or at least to minimize the damage from one that can't be avoided. In some countries and areas (e.g. Scandinavia and the U.S.A.), the pilot's role is as an advisor. However, in practice, they are likely to have the conduct of the vessel, especially on larger ships using tug boats to assist. The general rule of thumb is that a pilot assumes command of a vessel and is not classed as "an advisor" in the Panama Canal, crossing the sill of a drydock, or in any port in Russia (or, perhaps, all the old Soviet states). This distinction is important because when a pilot is in command, the master can not take any action, but is limited to advising the pilot on any circumstance that creates what he considers a dangerous situation.

Progression in Seamanship- In the days before mechanical propulsion, an able seaman was expected to be able to "hand, and reef, and steer". Training is more formal in modern merchant marines and navies, but still covers the basics.
The crew of a large ship will typically be organized into "divisions" or "departments", each with its own specialty. For example, the deck division would be responsible for boat handling and general maintenance, while the engineering division would be responsible for propulsion and other mechanical systems.





Crew start on the most basic duties and as they gain experience and expertise advance within their area. Crew who have gained proficiency become "able seamen", "petty officers", "rated", or "mates" depending on the organization to which they belong.
On smaller commercial craft, there is little or no specialization. Deck crew perform all boat handling functions. The officers of the ship are responsible for navigation, communication, and watch supervision.

Captains must pass formal examinations to demonstrate their knowledge. These examinations have a progression based on the size and complexity of the craft. In the U.S., the progression begins with what is known as "the six pack", a license that allows fishing guides to operate with up to six passengers.

International Maritime Law-a fraudulent breach of duty by the master of a ship that injures the owner of the ship or its cargo; includes every breach of trust such as stealing or sinking or deserting the ship or embezzling the cargo.

Weather and Metreorological forecasting- is the application of science and technology to predict the state of the atmosphere for a given location. Human beings have attempted to predict the weather informally for millennia, and formally since the nineteenth century. Weather forecasts are made by collecting quantitative data about the current state of the atmosphere on a given place and using scientific understanding of atmospheric processes to project how the atmosphere will evolve on that place.
Once an all-human endeavor based mainly upon changes in barometric pressure, current weather conditions, and sky condition, weather forecasting now relies on computer-based models that take many atmospheric factors into account. Human input is still required to pick the best possible forecast model to base the forecast upon, which involves pattern recognition skills, teleconnections, knowledge of model performance, and knowledge of model biases.






The chaotic nature of the atmosphere, the massive computational power required to solve the equations that describe the atmosphere, error involved in measuring the initial conditions, and an incomplete understanding of atmospheric processes mean that forecasts become less accurate as the difference in current time and the time for which the forecast is being made (the range of the forecast) increases. The use of ensembles and model consensus help narrow the error and pick the most likely outcome.
There are a variety of end uses to weather forecasts. Weather warnings are important forecasts because they are used to protect life and property. Forecasts based on temperatureand precipitation are important to agriculture, and therefore to traders within commodity markets. Temperature forecasts are used by utility companies to estimate demand over coming days. On an everyday basis, people use weather forecasts to determine what to wear on a given day. Since outdoor activities are severely curtailed by heavy rain, snow and the wind chill, forecasts can be used to plan activities around these events, and to plan ahead and survive them.

Watch Standing- sea an AB watchstander's duties include standing watch as helmsman and lookout. A helmsman is required to maintain a steady course, properly execute all rudder orders and communicate utilizing navigational terms relating to heading and steering. A watchstander may be called upon to stand security-related watches, such as a gangway watch or anchor watch while the ship is not underway.

Operation of Deck Equipment- The many and varied duties of the deck department are probably the most important and interesting aboard a merchant ship. Upon those who spend their working hours topside falls a burden that ranges from chipping and scaling paint to the actual navigation of the vessel.
Merchant ships differ in size and complement, but the average ship that sails the seven seas today, bringing war material to our armies and those of our allies, generally conforms to a single pattern of manpower. The duties of those men also run true to form, more or less, but as the saying goes among seamen -- “different ship, different long splice.”




 All of which is translated as meaning that different ships and masters have their own way of doing things. Generally, however, they are similar.
Starting at the bottom is the Ordinary Seaman (OS) whose duties actually are to assist the able seaman. In reality, however, he is the deck utility man and may be called upon to do any one of many tasks.
The ordinary may be called upon to stand a lookout, to scale and chip paint, to paint, handle lines in the mooring of the ship, and to assist in the actual tying up and letting go of the vessel. The ordinary also assists in the handling and operation of all deck gear such as topping, cradling and housing of booms and he may also be asked to aid the carpenter in repair work.
It is likely that the ordinary may be allowed to act as helmsman, to read the draft markings or to act as cargo watch in the loading and discharging of cargo.
Calling the watch (the awakening of men, including officers, who are slated to go on watch, or to so remind them if they are awake) is another of the important duties of the ordinary. He also assists in emergency drills (lifeboat, abandon ship and fire) and keeps the passageways and heads in shipshape condition on the 4 to 8 watch. He may also work aloft or over the side.
The Able Seaman (AB), by law, must be able to perform any deck duties aside from the actual navigation of the vessel. In general his duties include the ability to splice wire or fibre line, to work aloft and over the side of the ship, to operate the deck machinery such as the windlass or winches, to paint and mix paint, to know the principles of cargo stowage, to be a good wheelsman and competent lookout, to overhaul and install any running or standing rigging on the ship, and to be able to sew, repair and mend canvas.
The AB must be a competent and certified lifeboatman, able to handle a lifeboat under oars or sail. He must know lifeboat equipment and be able to assume the duties of the cox’n or man in charge of the lifeboat. It will also be the duty of the AB to maintain the bridge in a clean and shipshape condition.








Next on the way up the deck department ladder is the Bo’sn (Boatswain), senior unlicensed man on the ship. He is the direct contact between the crew and the chief mate and he may be likened to a foreman in any industrial plant.
The Bo’s’n must be an experienced seaman and is held responsible for anything and everything in the maintenance, care and protection of deck equipment and deck cargo. He also supervises the securing of the ship for sea and the loading and discharging of cargo. In addition, the Bos’n assists the chief mate in ordering the deck stores.
The duties of the ship's Carpenter (Chips) are numerous. He is likely to be called upon to perform work which, in many cases, is beyond that which the term carpenter implies ashore. In short, he is both a seaman and a mechanic.
In addition to doing temporary or permanent wood construction aboard ship with hand tools, he is responsible for the operation of the anchor windlass, seeing that hatch wedges are driven properly, that the deck cargo is properly lashed and that the hatch battens are in place and secure.
The carpenter also repairs blocks, keeps the lifeboat davits in good order, builds temporary or permanent partitions, shores or braces weakened or damaged bulkheads, rigs a collision mat, builds a soft patch in the event of bulging or collision, replaces broken rivets and he will assume command of an emergency crew to repair damage in event of a collision.
A Quartermaster is not a fixture on all vessels. On the larger ships, he is primarily a wheelsman and maintains the bridge and its equipment in shipshape order. He is conversant with signaling procedure, stands a gangway watch in port (responsible for the safety and security of the ship as well as escorting persons aboard who have business) and he is able to perform the duties of an able seaman (splicing line, reaving a halyard, etc.).
“Day men,” those who work with the Bo’s’n, are usually picked for outstanding ability. They work from 0800 to 1700 and stand no night watches. Their duties are the maintenance of the ship, which includes operating the anchor windlass, winches and other deck machinery.







“Holding on” in an unfamiliar anchorage in bad weather can be the most anxious time of any cruise. It is foolish and false economy to proceed on a cruise with anchors & cable inadequate for the very varied bottom conditions and weather that will be encountered during any voyage. It is a common sight in many vessels that the ground tackle supplied is often far to light for the conditions an ocean going passage maker will be expected to anchor in. The types of bottom most often encountered in anchorages are one of the following:
1) Mud 
2) Sand
 
3) Rock
 
4) Rock overlaid with sand or mud
At one time or another each of these bottom types will be encountered so the type of anchor should be suitable, as far as possible, for each of these conditions. Broadly, anchors are of two types:
1) Stock type 
2) Stockless type
The old style ‘Pick” or Kedge anchor, the Danforth, Moorfast and Stato anchors are all stock anchors. The stock in this type of anchor is designed to keep the anchor upright on the bottom. The big disadvantage with stock anchors is they are difficult to stow neatly on deck. This problem is overcome with the pick anchor by making the stock portable. Most other anchors are of the stockless type; their stability on the bottom is dependant on the size and weight of their “crown” or “head”. 
The following is a diagram showing the most common types:
Anchor Types
Anchor Types



Of the types shown the Hall, Spek, AC 14, Pool, Danforth, Bruce and the CQR anchors are the most suitable for Trawler Yachts.

Holding Power

The efficiency of an anchor is expressed as its holding power in lbs versus its weight in lbs. The holding power is proportional to its projected fluke area, shear strength of bottom material and depth of penetration of the anchor into the bottom. The following is a table showing the approx.





holding power, for comparison purposes, of each anchor type in mud and sand:


Holding Power
Anchor
Mud
Sand
Hall
3:1
7:1
Spek
3:1
7:1
AC14
5:1
12:1
Pool
6:1
14:1
Danforth
9:1
20:1
CQR
9:1
20:1
Bruce
9:1
20:1
The Hall and Spek type are classed as low Holding Power (LHP) anchors and are most commonly seen on merchant ships.
The AC14 and Pool types are classed as High Holding Power (HHP) anchors.
The Danforth, CQR and Bruce anchors are classed as Very High Holding Power (VHP) anchors.

On the face of it the best choice of anchor for a Trawler Yacht would be one of the VHP types and certainly this is the case for bottom types 1 & 2. The trouble is in the other bottom types 3 & 4. No anchor can develop any bottom penetration and an anchors only asset in this situation is its dead weight. A better choice would be one of the HHP types which are smaller physically weight for weight than the VHP types. The HHP types are also much easier to stow on deck or in a hawse pipe. Weight of Anchor & Cable The best approach for assessing the weight of anchors and chain sizes is to use one of the Classification Societies Rules such as Lloyds. Each Society has formulae to calculate the Equipment Numeral (N.A.) for all types of Ships and Navigation Notations. The N.A. formulae is a very complex calculation which takes into account the vessels displacement, beam & length, frontal & profile areas, number of decks and freeboards. A table is provided from which the required number of anchors, their weight and the size and length of chain cable is derived.






The following is an example of one of these tables.
Windlass

21. As a rule a windlass of suitable power for the mass of anchors and the size of the chain is to be securely attached to the deck which is to be
efficiently strengthened and pillared.
22. The windlass is to be installed so that the chain
run between the hawse pipes and the chain locker
is as direct as possible. The moving parts of the windlass that are likely to cause accidents are to be properly guarded.

NA
Stockless Anchors
Chain Cables
Greater than
Less than
or
equal to
Number
Mess (kg)
Length of each
mooring line (m)
Nominal Diameter (mm)
Studless
Chain Cable
Stud Link chain cables
01
02
10
12
1
15
35
7
12
14
1
19
40
7
14
16
1
23
45
8
16
18
1
26
50
8
18
20
1
30
55
9
20
23
2(1)
33
60
9
23
26
2(1)
39
65
10
26
30
2(1)
45
70
10
30
35
2(1)
52
75
11
35
40
2(1)
62
80
12
40
45
2(1)
72
85
13
45
50
2
82
90
14
12.5





50
60
2
91
95
14
12.5
60
70
2
113
100
15
14
12.5
70
80
2
135
105
16
14
12.5
80
90
2
155
110
16
14
90
100
2
180
110
16
14
100
110
2
205
125
16
14
110
120
2
230
125
19
17.5
120
130
2
255
140
19
17.5
130
140
2
128
140
19
17.5
140
150
2
310
140
19
17.5
150
170
2
340
140
20.5
17.5
170
190
2
405
150
20.5
17.5
190
210
2
455
150
22
19
210
230
2
510
150
22
19
230
250
2
550
150
24
20.5
250
300
2
600
150
26
22
In the example in bold it can be seen that a vessel with N.A. between 70-80 requires 2 x 135kg (300lbs) anchors and 105 metres (345ft) of 14mm (9/16ths) chain.

The anchor weights in the table are for L.H.P. anchors. A reduction factor of 0.75 is allowed if a H.H.P. anchor is chosen. Q1 chain is mild steel and Q2 chain is high tensile steel. H.H.P. anchors must be coupled with Q2 chain.
 

Therefore the vessel in question could be equipped with the following: 2 x 100kg (220lb) Pool (N) Anchors 105metres (345ft) 12.5mm (1/2 inch) Q2 Cable This would provide holding power in mud of 600kg (1323lbs) and 1400kg (3100lbs) in sand.
 








The Watson 48™ for example has an N.A. of 50 and is specified with the following: 2 – 60Kg (132lb) Pool “N” High Holding Power Anchors. 180 metres (590ft) 13mm (1/2 inch) Short Link Chain.

Anchor Stowage

Anchors much over 60lbs are impossible to man handle and must self stow. This can be done with difficulty, by fitting a tilting bow roller system. By far the best is to have the anchors self stow in hawse pipes in the hull. This is not possible with most V.H.P types because they cannot be made to stow neatly against the hull. In steel vessels the hawse pipes need to be stainless steel with a stainless steel striker plate against the hull for the anchor to stow against. Yachts should always have both anchors connected for immediate deployment. Having the second (spare) anchor stowed on deck is not good practice.
A pair of 60Kg (135lb) Pool “N” anchors fitted to the Watson 48. The hawse pipes and striker plates are fabricated from 316 stainless steel and are designed so anchors self stow. Anchors and chain should always be procured from a reputable manufacturer and be supplied with traceable certificates.
A pair of 60Kg (135lb) Pool “N” anchors fitted to the Watson 48. The hawse pipes and striker plates are fabricated from 316 stainless steel and are designed so anchors self stow. Anchors and chain should always be procured from a reputable manufacturer and be supplied with traceable certificates.



Winches

For vessels up to about 60ft yacht windlasses such as those made by Maxwell and Muir are excellent except that they are not strong enough to ride on and must be fitted with chain stoppers. 24VDC electric systems are fine, however if the ship has a hydraulic system then this may be the preference. Larger vessels almost inevitably need custom built windlasses.
http://www.realtrawlers.com/images/stories/winche.jpg
A Lofrans “Titan B” windlass fitted to the Watson 48 showing the chain stoppers fitted for riding on, along with “Devils claws” for keeping anchors stowed tight against the hull while steaming. The chain stoppers are designed to withstand the breaking strain of the cable. The chain self stows directly into the chain locker below deck.








Chain Lockers

A Yacht should have watertight, self stowing chain lockers located immediately below the windlass spurling pipes. For safety their drains must be connected to the ships central bilge pumping system. Stud link chain is always preferable for stowing as it does not become knotted in the chain locker. In conclusion a ships anchoring gear, including the windlass, is of prime importance; it is always better to “kick for touch” when assessing anchor and cable requirements for an ocean passage maker.



Rope Work and Line Handling-
Ropework is commonly defined as the set of processes of making and repairing ropes; some, however, also include any other work that can be done with ropes, such as tying knots and splicing.

Actually, only a few of the "ropes" on a boat are called ropes, most are called lines.

Ropes or wires that hold up masts are collectively known as standing rigging and are called shrouds or stays (the stay connecting the top of the mast to the bow is called the forestay or headstay).





Ropes or wires that control the sails are known collectively as running rigging or lines. Those that

raise sails are called halyards while those that strike them are called downhauls. Ropes that adjust (trim) the sails are called sheets. These are often referred to using the name of the sail they control (eg. "main sheet", or "jib sheet").

Ropes used to tie the boat up when alongside are called docklines.
http://www.molossia.org/milacademy/knots.jpg
Some knots: 1. Splice 2. Manrope knot 3. Granny knot 4. Rosebud stopper knot 5. Matthew Walker knot 6. Shroud knot 7. Turks head knot 8. Overhand knot, Figure-of-eight knot 9. Reef knot or Square knot 10. Two half hitches



There are some ropes: A few examples, the bell rope (to ring the bell), a bolt rope (attached to the edge of a sail for extra strength), a foot rope (on old square riggers for the sailors to stand on while reefing or furling the sails), and a tiller rope (to temporarily hold the tiller and keep the boat on course). A rode is what keeps an anchor attached to the boat when the anchor is in use.

Making a rope

To make a rope, take a long length of twine or yarn and tie it to a rod of strong material. Loop it around a second rod, held at a distance. Take it back to the first rod, loop it around, and then once more back to the second, to which it is then tied. There should be three lengths of twine running between the two rods. Each person holding a rod then moves backward until the lengths are taut and then begins turning his rod counterclockwise. This continues until the twine has been tightly twisted; at this point, the securing knots are untied. The twine is then secured to the rods again (as if the piece of three twisted lengths is one) and run between them as before was, with three lengths between the rods. The holders again pull the material taut and begin turning, this time in the opposite direction. When the rope is tightly twisted, each end is whipped (see below) and then cut between the whipping and the rod.






Whipping frayed ropes

A whipping knot is a type of knot used to hold the frayed end of a rope together. The simplest sort, the common whipping, is done by taking a two-foot-or-greater length of strong string, forming a loop with it, three or four diameters of the rope in length, and lying it on the rope near the frayed end. The rest of the length is then tightly wrapped without overlapping around the rope, moving up the loop. When the end of the loop is nearly covered, pull the remaining free length of the string through the loop and then pull on both ends, which will pull the end of the loop under the whipping. Cut off the end of the rope close to the edge of the whipping and then cut off the two free lengths of string.


A somewhat simpler method is merely to cut off the fraying and wrap a few layers of tape, usually electrical tape, around the cut end.

Fusing frayed ropes

Fusion is a method of repairing a frayed end of a nylon or plastic rope through use of heat. Cut off the fraying at the end, light a candle or cigarette lighter, and hold the cut end a few inches above the flame until the fibers have melted and fused together. Allow the end to cool before touching it or setting it down.

Another method of fusing, somewhat weaker, is simply to cut the end, dip it in paint, and allow it to dry.









Sailing-

Sailing is motion across a body of water in a sailing ship, or smaller boat, powered by wind.

How sailing works

The force of the wind is used to create motion by using one or more sails. The movement of air over the sails acts in the same way as air moving over an aircraft's wing. Just like on an airplane, air flowing over the sail is deflected and accelerated. This generates lift, which acts to pull the sail, and thus the boat ahead, but also slightly downwind. The downwind component is offset by an underwater hydrofoil (centerboard or keel), whose shape resists lateral movement while offering little resistance to forward motion. Without a keel or centerboard, sailing upwind or across the wind would be virtually impossible. (Other sailing hydrofoils include daggerboards and leeboards).

The lifting force of the sails also acts to lean the boat over to one side, which is called heeling. This is counteracted by ballast, either in the form of dense material located in the keel (usually lead or iron) or in the form of human or water ballast located near the windward rail.

Today, for most people, sailing is a hobby. Pleasure sailing can be further divided into two areas: Racing and Cruising.

In ancient times (see Odysseus), ships used following or rear-quarter winds. Therefore, they had to wait in port or at sea for the right wind directions.

Basic sailing techniques

Turning a sailing boat

There are four basic maneuvers a sailing boat can perform while underway. They are:

Tacking is turning the boat so that the bow passes through the eye of the wind (or "no go zone").
Gybing (or wearing) is turning the boat so that the stern of the boat turns through the wind. Gybing causes the boom to swing from one side to the other, sometimes rapidly, as the wind catches the leach of the mainsail on its new upwind side.



Heading up is turning the boat to sail closer to the direction the wind is coming from.
Bearing away (or falling off) is turning away from the direction the wind is coming from.

Trim
An important aspect of sailing is keeping the boat in "trim". And remembering to let go of the rope. To achieve this a useful mnemonic (memory aid) is the phrase:

Can This Boat Sail Correctly?

This helps the crew to remember these essential points;

Course to Steer - Turn the boat using the wheel or tiller to the desired course to steer. See points of sail. This may be a definite bearing (e.g steer 270 degrees), or towards a landmark, or at a desired angle to the apparent wind direction.
Trim - This is the fore and aft balance of the boat. The aim is to adjust the moveable ballast (the crew!) forwards or backwards to achieve an 'even keel'. On an upwind course in a small boat, the crew typically sit forward, when 'running' it is more efficient for the crew to sit to the rear of the boat. The position of the crew matters less as the size (and weight)of the boat increases.
Balance - This is the port and starboard balance. The aim, once again is to adjust weight 'inboard' or 'outboard' to prevent excessive heeling.
Sail - Trimming sails is a large topic. However simply put, a sail should be pulled in until it fills with wind, but no further than the point where the front edge of the sail (the luff) is exactly in line with the wind.
Centreboard - If a moveable centreboard is fitted, then it should be lowered when sailing "close to the wind" but can be raised up on downwind courses to reduce drag. The centreboard prevents lateral motion and allows the boat to sail upwind, and also provides stability to keep the boat from rolling over. A boat with no centreboard will instead have a heavy permanent keel built into the bottom of the hull, which serves the same purposes.

Running Downwind

Sailing the boat within 30 degrees of straight downwind is called a run. This is the easiest point of sail, but it can also be the most dangerous. Sailing upwind gives you the everpresent possibility of stopping the boat easily by steering into the wind. Running gives a sailor no such easy out. Be careful and either use your boom vang or adjust the mainsheet to prevent an accidental gybe.



Beating an upwind course

A basic rule of sailing is that it is not possible to sail directly into the direction the wind is coming from. Generally a cruising boat can sail 45 degrees off the wind, a racing boat may aproach 35 degrees. However since it is often necessary to move towards the wind direction, it is necessary to 'beat' upwind.

Beating is simply a series of 'tacks' where the boat sails as close to the wind on each tack as possible, and then switches sides and repeats the process. By this method, it is possible to travel directly into the wind. The heavier the wind the harder the beat, and since you are sailing into oncoming waves at an angle, boat movement can be heavy. This movement can feel like the boat is beating its hull into the waves, hence the name. Since the boat is sailing over oncoming waves, a beat will feel faster than its actually moving.

During a beat, it is important to watch your heading, since the wind will tend to push an unbalanced boat into or away from the wind, depending on the balance problem. If you find yourself having to overcorrect at the helm for sail pressure into the wind, then you are in a condition called weatherhelm, and you are actually slowing the boat with your rudder. To correct this, reduce sail.
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Reducing sail

An important safety aspect of sailing is to adjust the amount of sail to suit the wind conditions. As the wind speed increases the crew should progressively reduce the amount of sail. On a small boat with only jib and mainsail this is done by furling the jib and by partially lowering the mainsail, a process called 'reefing the main'.

Reefing basically means reducing the size of a sail without changing them. Ideally reefing does not only result in a reduced sail area but also in a lower center of effort from the sails, keeping the boat more upright.

There are three core methods of reefing the mainsail: - Slab reefing, which involves lowering the sail by about one-quarter to one-third of its luff length and tightening the lower part of the sail using an outhaul through a cringle at the new clew, and hook through a cringle at the new tack. - In-mast (or on-mast) roller-reefing. This method rolls the sail up around a vertical foil either inside a slot in the mast, or affixed to the outside of the mast. It requires a mainsail with either no battens, or newly-developed vertical battens. - In-boom roller-reefing, with a horizontal foil inside the boom. This method allows for standard- or full-length horizontal battens.

Mainsail furling systems have become increasingly popular on cruising yachts as they can be operated shorthanded and from the cockpit in most cases, however, the sail can become jammed in the mast or boom slot if not operated correctly. Mainsail furling is almost never used while racing because it results in a less efficient sail profile. The classical slab-reefing method is the most widely used. Mainsail furling has an additional disadvantage in that its complicated gear may somewhat increase weight aloft. However, as the size of the boat increases, the benefits of mainsail roller furling increase dramatically.

Sail trimming

As noted above, sail trimming is a large subject. Basic control of the mainsail consists of setting the sail so that it is at an optimum angle to the wind,(i.e. no flapping at the front, and tell tales flowing evenly off the rear of the sail).

Two or more sails are frequently combined to maximise the smooth flow of air. The sails are adjusted to create a smooth laminar flow over the sail surfaces. This is called the "slot effect". The combined sails fit into an imaginary aerofoil outline, so that the most forward sails are more in line with the wind, whereas the more aft sails are more in line with the course followed. The combined efficiency of this sail plan is greater than the sum of each sail used in isolation.





More detailed aspects include specific control of the sail's shape, e.g.:

reefing, or reducing the sail area in stronger wind
altering sail shape to make it flatter in high winds
raking the mast when going upwind (to tilt the sail towards the rear, this being more stable)
providing sail twist to cope with gusty conditions

Heeling

When a boat rolls over to one side under wind pressure, it's called 'heeling'. As a sailing boat heels over beyond a certain angle, it begins to sail increasingly inefficiently. Several forces can counteract this movement.

The buoyancy of that part of the hull which is being submerged tends to bring the boat upright.
Pressure on the centreboard or keel moving at a slight 'leeway' angle through the water tends to balance the rolling force.
Raising the centreboard can paradoxically increase leeway, and therefore reduce heeling.
A weighted keel provides additional force to right the boat.
The crew may move onto the high (upwind) side of the boat, called hiking, changing the centre of gravity significantly in a small boat.
They can trapeze where the boat is designed for this. The underwater shape of the hull relative to the sails can be designed to make the boat tend to turn upwind when it heels excessively: this reduces the force on the sails, and allows the boat to right itself.
The boat can be turned upwind to produce the same effect.
Wind can be spilled from the sails by 'sheeting out', i.e. loosening the sail.
Lastly, as the boat rolls farther over, wind spills from the top of the sail.
Most of the above effects can be used to right a heeling boat and to keep the boat sailing efficiently: if however the boat heels beyond a certain point of stability, it can capsize.

Sailing close to the wind
How close a boat can sail to the wind depends on the wind speed, since what the boat "sees" is the apparent wind, i.e., the vector sum of the actual wind and the boat's own velocity. The apparent wind is what the windex on top of the mast shows. Because of this, people often talk about how close a boat can sail to the apparent wind. A good, modern sloop can sail within 25 degrees of the apparent wind. An America's Cup racing sloop can sail within 16 degrees, under the right conditions. Those figures might translate into 45 degrees and 36 degrees relative to the actual wind. The angles at which the wind meets the boat are described by the points of sail.





Sailing safety

First and foremost:

Learn to swim!
Wear a life vest!
Sailing is intrinsically dangerous, since water is not our natural element. All sailors therefore should take precautions, and when engaged in publicly organised activities they must take certain precautions, as detailed by the authority which regulates the training or racing.

Safety measures include:

Provision of a safety boat for rescue purposes
Appropriate first aid and firefighting equipment
Carrying of a knife suitable for cutting rigging or netting which may entrap a sailor underwater
Wearing of buoyancy aids
Understanding and practice of man overboard procedures such as the Anderson turn, the Williamson turn, and the Scharnow turn.

Also, know the 'rules of the road':

Port tack gives way to Starboard tack (when the paths of two boats on opposite tacks cross, the boat with its port side to windward must give way)
Windward gives way to the leeward, or downwind boat (if on the same tack)
Overtaking boat gives way if above do not apply
Non-Commercial Powerboats usually give way to sailboats (but be careful in shipping lanes, and use common sense)
It is everybody's responsibility to avoid a collision, and avoiding action must be taken if these rules are ignored.

Sailing hulls and hull shapes

Sailing boats can have one, two, or three hulls. Boats with one hull are known as monohulls, while those with two or more are known as multihulls. Multihulls can be further subdivided into catamarans (two hulls), and trimarans (three hulls). A sailing boat is turned by a rudder which itself is controlled by a tiller or a wheel. Smaller sailing boats often have a stabilising, raisable, underwater fin called a centreboard (or daggerboard); larger sailing boats have a fixed (or sometimes canting) keel. As a general rule, the former are called dinghies, the latter yachts. 





Multihulls use flotation and/or weight positioned away from the centre line of the sailboat to counter the force of the wind. This is in contrast to heavy ballast that can make up to 1/3 of the weight of a monohulled sailboat. In the case of a standard catamaran there are two similarly sized and shaped narrow hulls connected by a deck superstructure. Another catamaran variation is the proa. In the case of trimarans, which have an unballasted centre hull similar to a monohull, two relatively smaller amas are situated parallel to the centre hull to resist the sideways force of the wind. The advantage of multihulled sailboats is that they do not suffer the performance penalty of having to carry heavy ballast, and their relatively smaller hulls reduce the amount of drag caused by friction and inertia when moving through the water.

Types of Sails and layouts

On a modern yacht, the mainsail or main is usually the primary driving sail, triangular in shape, and fixed to the largest (or often the only) mast. A headsail, either a jib or genoa, is set in front of the mainsail, attached in such a way that the trailing edge extends back alongside the main. This is also known as an overlapping headsail (pronounced hedsal). Two or more headsails can be used. In addition, some sailboats, ketches and yawls, have another smaller mast called the mizzen mast, on which is set a smaller sail similar to the mainsail and called the mizzen sail.

A spinnaker is a large, full sail that is only used when sailing off wind either reaching or downwind, to catch the maximum amount of wind.

Sailing regulations

There are two very basic rules for avoiding a collision at sea: 1) Power gives way to sail 2) Port gives way to starboard. This second point means that yachts who have their sails set for a breeze coming from the left hand side of the boat (the port side) must give way to yachts that have their sails set for a breeze coming from the opposite side of the boat (the starboard side). If both yachts have their sails set on the same side of the boat, then the yacht closer to where the wind is coming from must give way. This rule is described as the windward boat must keep clear of the leeward boat.

However there are many other rules besides and sailors are expected to know the essentials of boating safety which include;

The rules of the road or International Regulations for Preventing Collisions at Sea set forth by the International Maritime Organization are particularly relevant to sailors because of their limited maneuverability compared to powered vessels.
The IALA International Association of Lighthouse Authorities standards for lateral marks, lights, signals, and buoyage and various rules designed to support safe navigation. 



The SOLAS (Safety of Life at Sea) regulations place the obligations for safety on the owners and operators of any boat. These regulations specify the safety equipment needed and emergency procedures to be used.

Sailing traditions and etiquette

There are many, more esoteric, etiquette rules, traditions, and customs that will demonstrate to others advanced knowledge of boating protocol. Fenders should be pulled up outside ports, the flag of the host country should be shown, flags are to taken down at night, one should not walk on other's forecastle, no whistling aboard etc



















                                                 PARTS OF THE MODERN SHIP


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                                                 PARTS OF THE PASSENGER SHIP

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                                          PARTS OF THE PASSENGER SHIP
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