Chapter 6
Seamanship: Continued

A. Boats

6A1. Types and uses. Boats used by the United States Navy are divided into two general classes: power boats, and (2) pulling boats (propelled by oars). As a war measure, the number and types of boats carried aboard naval vessels have been reduced greatly, the largest ships carrying not more than two boats, or possibly four in the case of aircraft carriers. However, in and around navy yards, operating bases, and anchorages a variety of types are still in use.

Power boats may be classified as follows:

  1. Motor whaleboats are light, double-ended, open boats with high bows and sterns. Their interior is divided into three distinct compartments with the engine (ordinarily Diesel) occupying the middle one. They are equipped with watertight, metal air tanks to increase their buoyancy and are particularly well adapted for use at sea, as lifeboats, or for any other service for which boats are necessary. Generally speaking, the motor whaleboat has replaced all others aboard ships since our entry into the war.

  2. Motor launches are heavy open boats with square sterns ranging from 24 feet to 50 feet in length. They are no longer carried aboard ship but are used in port for heavy work, and for carrying stores and liberty parties.

  3. Motorboats are fast, decked-over boats with square sterns. They are used principally to carry officers. Motorboats assigned for the personal use of officers of flag rank are called barges. Those assigned for the personal use of commanding officers, chiefs of staff, etc., not of flag rank are called gigs.

Pulling boats may be classified as follows:

  1. Whaleboats are similar to motorboats except that they have no engine and are pulled with either 5 or 6 oars single-banked, or 12 oars double-banked. They carry air tanks for buoyancy and are generally used as lifeboats. They are generally used at shore training stations, but may be found aboard many of our smaller ships today.

  2. Dinghies are square-sterned open boats pulled with 4 oars in a single bank. They are used chiefly for training, recreation, and light work.

  3. Wherries are square-sterned open boats which are light, handy, and can be pulled by one man.

  4. Punts are rectangular, flat-bottomed boats used for painting and general cleaning around the waterline.

  5. Cutters are double-banked, square-sterned boats pulled with 10 oars. They are used for training purposes at shore stations.

Each boat has a label plate containing data applicable to that particular boat, similar to that shown in Figure 6-1.

6A2. Nomenclature of boat parts. The recognized nomenclature of the principal parts of boats and their fittings is as follows:

  1. Apron: a timber fitted abaft the stem to reinforce the stem and give a sufficient surface on which to land the hood ends of the planks.

  2. Beams: transverse supports running from side to side to support the deck.

  3. Bilge: the part of the bottom, on each side of the keel, on which the boat would rest if aground.

  4. Binding strake: a strake of planing, fitted next to and under the sheer strake.

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  1. Blade, oar: the broad flattened part of an oar as distinguished from the loom.

  2. Boatfalls: lead blocks and tackles with which the boats are hoisted aboard at davits.

  3. Boathook: a pole with a blunt hook on the end to aid in landing or hauling alongside.

  4. Boat plug: a screwed metal plug fitted in the bottom planking of the boat at the lowest point to drain the bilges when the boat is out of the water.

  5. Boom: a spar rigged to a mast or kingpost for use in handling heavy weights.

  6. Bottom boards: the fore-and-aft planks secured to the frames, or to floor beams, forming the walking flat of the boat, frequently removable for access; sometimes called floor boards or footings.

    Figure 6-1. A boat label plate.
    Figure 6-1. A boat label plate.

  7. Braces, rudder, upper and lower: straps of metal secured to the rudder, the forward ends of which are formed into eyes or gudgeons which fit over the rudder hanger or pintles of the transom or sternpost, thus securing the rudder and forming a pivot upon which the rudder swings.

  8. Breaker: a small cask for carrying potable water.

  9. Breastbook: a wood or metal knee fitted as a bracket behind the stem structure.

  10. Cabin: a compartment, usually for passengers, in a covered boat.

  11. Capping: a fore-and-aft finishing piece on top of the clamp and sheer strake, at the frame heads, in an open boat; called a coverng board or margin plank or planksheer in a decked-over boat.

  12. Carling: a fore-and-aft beam at hatches.

  13. Chain plate: a metal plate with an eye in the upper end fitted at the deck edge or gunwale to take the shroud whips; also used for steadying lines (side legs) during lifting.

  14. Chock: a metal casting used as a fairlead for a mooring line or anchor chain.

  15. Clamp: a main longitudinal strength member at the side and under the deck beams in decked over boats, and in open boats at the gunwale.

  16. Cleat: a horned casting for belaying lines.

  17. Cockpit: an uncovered compartment, in a boat, usually for passengers.

  18. Deadwood: timber at the after end of the boat connecting the keel to the end timbers.

  19. Fenders: portable wooden or rope sennit bumpers hung over the side during landings to protect the hull.

  20. Flat: a walking surface in the engine room or any special platform, such as the coxswain's flat.

  21. Floors: transverse timbers which reinforce the frames and carry the strength athwartship across the keel.

  22. Footings: bottom boards of walking flats attached to the insides of the frames on boats not fitted with deep floors.

  23. Foresheets: the portion of the boat forward of the foremost thwarts.

  24. Frames: the ribs of the boat; curved members, usually steam bent, secured to the keel and extending upward to the gunwale or deck. In some types of construction sawed frames are used.

  25. Garboard: the lowest strake of outside planking next to the keel.

  26. Gripes: the fittings used to secure a boat in its stowage position on board ship. For boats secured at the davitheads, gropes are made of tarred hemp woven into a sword mat and faced with canvas,

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    to hold the boat against the strongback; for lifeboats, the lower ends of the gripes are usually fitted with a slip-hook. For boats secured in cradles, the gripes are usually of metal, tightened with turnbuckles, and arranged to prevent the boat from shifting in the cradles due to the motion of the ship in a seaway.

  1. Gudgeons: metal fittings, provided with eye sockets, secured to the sternpost to receive the rudder pintles.

  2. Gunwale: the upper edige of the side of an open boat.

  3. Hanger, rudder: a vertical strip of metal, secured to the sternpost, forming the traveler upon which the rudder braces are secured.

  4. Hoisting pads: metal fittings inside the boat usually attached to the keel to take the hoisting slings or hoisting rods.

  5. Keel: the principal longitudinal timber of a boat, extending from stem to stern at the bottom of the hull and supporting the whole structure.

  6. Keel stop: a small metal fitting on the keel, at the after end, to act as a stop in locating the boat in a fore-and-aft position on the keel rest when stowing the boat in the cradle.

  7. Keelsons: fore-and-aft structural timbers fitted either above or outboard of the keel.

  8. Knee: a shaped timber for connecting structural members installed at an angle to each other.

  9. Leather: that portion of an oar which rests in the rowlock. This is usually covered with leather.

  10. Loom: the rounded portion of an oar extending from blade to handle.

  11. Painter: a rope used in the bow, for towing or for securing the boat.

  12. Pintles: metal pivot pins secured to the rudder and fitting in the gudgeons on the sternpost, thus supporting the rudder. Pintles and gudgeons are used in place of rudder braces and hangers fitted on some boats.

  13. Planksheer: the outermost deck plank at the side.

  14. Risings: the fore-and-aft stringers inside a boat,secured to the frames, on which the thwarts rest.

  15. Rowlocks: forked pieces of metal in which the leathers of oars rest while pulling. Sunken rowlocks are those which are set down into the gunwale of the boat.

  16. Sheer: the line of form at the side which the gunwale or deck edge follows in profile.

  17. Sheerstrake: the uppermost strake of planking at the side, following the line of sheer.

  18. Side fender: a longitudinal timber projecting beyond the outside lines of the hull planking, often metal-faced, to protect the hull.

  19. Slings: gear made of wire rope and close-link chain for handling boats at booms or cranes.

  20. Steering rowlock: a form of swivel rowlock, fitted near the stern of a whaleboat, in which the steering oar is shipped; sometimes called a crutch.

  21. Stem: the upright timber in the forward part of a boat, joined to the keel by a knee.

  22. Stemband: a metal facing or cutwater fitted on the stempost.

  23. Stemheel or forward deadwood: a timber often called the sole piece forefoot, and used to connect the stem knee to the keel.

  24. Stern fast: a stern painter for use in securing the stern of a boat.

  25. Stern hook: same as breasthook, for stern on a double-ended boat.

  26. Sternpost: the principal vertical piece of timber at the after end of a boat, its lower end fastened to the keel or shaft log by a stern knee.

  27. Stern sheets: the space in a boat abaft the thwarts.

  28. Strake: continuous line of fore-and-aft planking. Each line of planking is known as a strake.

  29. Stretchers: athwartship, movable pieces against which the oarsmen brace their feet in pulling.

  30. Stringers, bilge: longitudinal strengthening timbers inside the hull.

  31. Strongback: the spar between the davits against which a boat is griped in.

  32. Thole pin: a pin fitted in the gunwale capping for use in place of a rowlock; used with a Manila ring about 5 inches in diameter called a thole pin grommet.

  33. Tiller: a bar or lever, fitted fore-and-aft in the rudder head, by which the rudder is moved.

  34. Topping lift: a line used for supporting or topping up a beam.

  35. Towing bitts or towing posts: vertical timbers securely fastened, for use in towing or mooring.

  36. Trailing lines: small lines secured to the boat and around the oars to prevent the latter from getting adrift.

  37. Transom: the planking across the stern.

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Figure 6-2. Motor whaleboat at the davits.
Figure 6-2. Motor whaleboat at the davits.

  1. Yoke: athwartshp piece fitting over the rudder head, and by which the rudder is moved by yoke ropes when the tiller is not shipped.

6A3. Handling and stowage of boats. In most cases, only two motor whaleboats are carried aboard ship, although some of the larger vessels may carry two motor launches in addition. Occasionally, in the case of smaller ships, pulling boats may be aboard. When two boats are furnished, one boat is carried on each side, amidships, or on the quarters. They are ordinarily carried at davits swung outboard and ready for immediate disposal or use. While all boat cranes have been removed so that their topside4 weight may be replaced with additional armament, some ships use a boom and topping lift to handle boats. In this case, the boom is so rigged that the hauling part of the falls may be led to a power winch. When handling boats from davits, the falls may be led to a winch or manned by the crew. Aircraft carriers may carry as many as four boats, usually rigged to power davits beneath the overhang of the flight deck on each side and on a level with the hangar deck.

Slings. When a motor whaleboat is to be handled with a boom, there is only one set of falls and only one hook from which to suspend the boat. Therefore, it is necessary to provide a three-legged wire rope sling, rigged as in Figure 6-3 with a ring which engages the hook of the boom block.

Releasing gear: safety runner. For releasing the sling rung from the hook after the boat is lowered into the water, and for placing it over the hook when hoisting out, a tripping line and safety runner are used. The safety runner is a wire about 31/2 fathoms long. One end is secured to the bill of the hook (see Figure 6-4). The wire runs along the hook and through the ring (the ring being placed on the hook and over the bight of the runner), and then up and inboard, where it terminates in an eye to which the tripping line is bent by means of a snap hook or a hitch. The tripping line is then led through a block on the boom and thence down to the deck, where it is belayed and coiled free for running. When the boat is water-borne, a pull on the tripping line from deck straightens the bight of the safety runner, and lifts the ring clear of the hook. In hooking on, the bight of the safety runner is lowered so that it may be reached and disconnected at the snap hook or shackle by the boat's crew. It is then passed through the

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Figure 6-3. Handling a boat with slings.
Figure 6-3. Handling a boat with slings.

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Figure 6-4. Left, hooking on. Upper right, safety runner and tripping line. 
Lower right, safety runner ready for unhooking.
Figure 6-4. Left, hooking on. Upper right, safety runner and tripping line. Lower right, safety runner ready for unhooking.

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Figure 6-5. Raymond releasing hook.
Figure 6-5. Raymond releasing hook.

ring and connected to the tripping line. A pull on the tripping line will then cause the hook to engage the ring (see Figure 6-4).

Raymond releasing hooks. When a motor whaleboat is handled from davits (see Figure 6-2), it is, of course, suspended at the bow and stern from separate falls. The lower fall block usually has attached to it an automatic hook known commercially as the Raymond releasing hook. The gear consists simply of a tumbling hook (see Figure 6-5) made in two parts and pivoted. The outer part, which forms the end of the hook, is so weighted that when the boat is water-borne, the point of the hook "tumbles" releasing the boat. When the boat is not water-borne, its weight prevents the tumbling of the hook. To facilitate attaching the hook to a water-borne boat prior to hoisting, a lanyard made fast to the point of the hook is rove through the boat shackles.

6a5. Sea-painter. To sheer the boat clear of the side of the ship when it is water-borne, a sea-painter is used. This is a long line secured by a toggle over the inboard gunwale in the bow of the boat. It is led outboard of all rigging and well forward where it is tended on the deck of the ship. A pivoting point is thus created on the inboard bow of the boat. As the boat and ship have headway, the resultant pressure of water on the bow of the boat causes it to sheer away from the side of the ship (see Figure 6-6). This is always supplemented by action of the coxswain with the rudder.

6A6. Boats ready for lowering. Boats carried aboard must now serve a variety of purposes, but whatever use may be be required of them, they are always ready for use as lifeboats. For that reason the instructions regarding lifeboats are followed generally.

    Pulling boats. A pulling lifeboat is ready for lowering when in the following condition:

  1. The crew of the watch have been mustered, each man abreast of his own thwart (or station) of the lee boat, and each man understands his duties at "Man overboard." This includes the men for lowering, for observing the man overboard, unhooking the falls, tending the sea-painters, and for signaling.

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Figure 6-6. Acting of sea-painter and method of securing.
Figure 6-6. Acting of sea-painter and method of securing.

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  1. Boat at the davits, griped in securely against the strongback, with chafing pads between the boat and the strongback, and the gripes secured by toggle or pelican hook, ready for instant freeing.

  2. In older installations, the falls are rove continuous between davit heads; in later installations, separate falls are used. In either case, automatic releasing hooks are fitted. At night, the falls are coiled down on deck or in racks and clear for running; during the day, coils may be triced up to the davit with becket and toggle.

  3. Detaching apparatus (including automatic releasing hooks) ready for detaching at the order.

  4. The sea-painter led from a point well forward on the ship, outside of everything, half hitched around the inboard end of the second thwart and secured with a toggle, and if necessary, stopped up out of the water by a rope yarn.

  5. The knotted life lines, one for each member of the crew, hang from the span, for use in case of emergency in lowering or hoisting.

  6. Life jackets, one for each member of the boat crew and passengers, stowed in a locker adjacent to the lifeboat so that the crew may don them before manning the boat. If this is not practicable, life jackets secured in place, one under each position occupied in the boat when the boat is lowered.

  7. Steering oar shipped in crutch.

  8. Oars fitted with trailing lines and ready for getting out quickly.

  9. Rowlocks shipped and fitted with lanyards.

  10. Bilges dry.

  11. Boat plugs in place.

  12. Lantern filled and trimmed and placed in bucket when not in use (and at night, lighted).

  13. Suitable light for blinker signaling.

  14. All articles of boat equipment, except sails and spars, ready for use.

  15. Two day's supply of water and provisions for the crew.
    Power boats. A power boat is ready for lowering when:

  1. The crew of the watch have been mustered each at his station in the boat or at the falls or boom and each man understands his duties at "Man overboard." This includes the men for handling the boom or falls, steadying lines, tripping line, sea-painter, and for signaling.

  2. Boats set up in chocks and griped down securely with gripes fitted with quick releasing pelican hooks or toggles. If at the davits, see Pulling Boat.

  3. Power on the winch or if at the davits, the falls rove at davitheads and automatic releasing hooks fitted. At night, the falls are coiled down on deck or in racks and clear for running; during the day, the coils may be triced up to the davit with becket and toggle.

  4. The sling ring hooked on the boom block and the tripping line, used to release the sling ring from the hook on the boom fall, rove off, clear,and coiled down ready for paying out as boat is hoisted out and lowered. If at the davits, detaching apparatus is ready for detaching at order.

  5. Forward and after steadying lines rigged and coiled down ready for paying out when the boat is hoisted out and lowered.

  6. Sea-painter secured to thwart as in the pulling whaleboat, and led clear.

  7. Fuel tank full.

  8. Lubricating oil reservoir full and reserve can of lubricating oil in boat.

  9. Engine tested twice daily, once just before sundown.

  10. Required fire-extinguishers in boat.

  11. Life jackets, one for each member of the crew, stowed in a locker adjacent to the lifeboat so that the crew may don them before manning the boat. If this is not practicable, life jackets must be secured in place, one under each position occupied in the boat when the boat is lowered.

  12. Bilges dry.

  13. Boat plugs in place.

  14. Lantern filled and trimmed and placed in bucket when not in use (and at night, lighted).

  15. Suitable light for blinker signaling.

  16. All articles of boat equipment ready for use.

  17. Two day's supply of water and provisions for the crew.

6A7. Lowering. At "Man overboard," all members of the lifeboat crew of the watch, and men for hoisting out and lowering away, go to their stations on the run. The lee lifeboat or the lifeboat designated by the officer of the deck's order, "Clear away the starboard (or port) lifeboat!" is manned.

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Figure 6-7. Lowering a pulling lifeboat.
Figure 6-7. Lowering a pulling lifeboat.

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The crew don life jackets and immediately take their positions in the boat. If the boat is at the davits, the crew then, if not otherwise engaged, seize life lines as a safety precaution in case of accident. When all members of the crew are in the boat, the gripes are tripped and, if the boat is in the skids, the grips are cleared away.

To keep the boat from swinging, frapping lines, lizards running on jackstays, or steadying lines should be used. The frapping lines are passed around the boatfalls and the ends led to, and handled on, deck. The lizards are kept in hand in the boat, after passing a turn with each around a thwart. Under no conditions are the lizards to be so secured at the boat that they can jam. The steadying lines may be secured in the boat or held in hand, after taking a turn with each around a thwart. They are tended by men on deck. Members of the crew, in the waist, man boathooks to breast off the ship's side. They must be careful to hold the ends of the boathooks above the outer gunwale to avoid the possibility of staving a hole in the boat.

Members of the boat crew stand by the releasing gear or to clear the sling ring in case the tripping line fouls. One member stands by to slip the sea-painter.

When all is ready, the one in charge commands "Lower away together," or if the boat is on the boom and in the chocks, "Hoist away," and "Swing out and lower away."

Strain is taken on frapping lines, lizards, and steadying lines, and the boat is steadied by men in the waist with the boathooks. The necessary slack is taken in on the sea-painter. The sea-painter toggle is pulled and the end held in hand by a man in the boat. One turn of the painter should be taken about the inboard side of the second thwart. In boats at davits, men must tend the falls to keep them clear and to keep the blocks from striking other members of the crew when they are let go. In case a tumbler hook is used, these men grasp the tumbler lanyard to unhook the falls in case they do not unhook automatically. If the boat is not supplied with detaching apparatus, these men unhook the falls.

The boat must be lowered smartly, especially in rough weather. When the boat is at the davits, the falls must invariably be lowered together. While being lowered, the crew not otherwise engaged stand by their oars, or the engineer starts the engine.

If being lowered from davits, the boat officer, or in his absence the coxswain, lets go the detaching apparatus or gives the command"Let go," when the boat is a short distance from the water. If the boat is not fitted with detaching apparatus, the boat officer, or in his absence the coxswain, commands "Let go the after fall," then "Let go the forward fall," as soon as the boat is water-borne. The after fall is always let go first.

If being lowered from a boom, the hook is tripped when the boat is water-borne and the sling ring thereby unhooked.

At this instant the greatest hazard in lowering the lifeboat exists, as there is then the danger of the boat being dashed against the ship's side. Smartness in handling the boat is demanded. Lizards and steadying lines are cast off. The coxswain gives the stern a sheer in with the steering oar or rudder to get the bow out. The strain on the sea-painter sheers the boat clear of the side. When clear of the side, the officer (or coxswain,in case no officer is present) commands "Cast off sea-painter."

An ax or hatchet should be ready for use to clear a jam at this critical moment.

When the boat is clear, thwartmen get out oars or the engineer engages the clutch, and the boat makes the best of her way to the rescue.

It is important that the ship have some headway, and under no circumstances sternway, when the lifeboat is launched.

Hoisting. The same general principles of seamanship apply as in lowering. It is preferable for a ship to have a little headway on in case she is underway. The important point is to keep the boat off the ship's side to prevent its being damaged.

The boat should never had to wait for preparations on deck. Boatfalls should be well overhauled, led along the deck and well manned or taken around the drum of the winch, which should be turned at the desired speed before the order "Hoist away." The boom hook should be lowered clear of the heads of the crew. The frapping lines, lizards, or steadying lines, and the sea-painter should be made ready to pass to the boat. The boom hook tripping line, which is used in hooking on, is made ready for passing to the boat.

All being ready on deck and a lee having been made, the boat comes alongside and takes the sea-painter which is hove to her. The sea-painter is passed with one turn about the inboard end of the forward thwart, and its end held in hand.

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Figure 6-8. Boat beginning to back, left rudder.
Figure 6-8. Boat beginning to back, left rudder.

The ship has some way on her, and once the sea-painter is passed about the thwart and a strain taken thereon, by proper use of the steering oar or rudder the coxswain can hold the boat at the desired position off from the ship's side. By judicial easing of the oar or rudder, the sheer in of the stern may be lessened and the boat brought in slowly to the ship. If the boat should lurch toward the ship, the danger of being crashed against the side may be quickly offset by increasing the sheer in of the stern and sheer out of the bow, with the oar or rudder. The strain on the sea-painter will then pull the boat clear. Do not make the sheer off so radical that swamping of the boat must be offset by casting off the sea-painter.

The boat is hauled under the davits or boom by manning the sea-painter on the deck.

The frapping lines, lizards, or steadying lines, and the tripping line are now passed. When hoisting in with the boom, the tripping line is rove through the sling ring and made fast to the eye of the safety runner.

If the ship has much way on, a line should be led from the stern of the boat to a point well aft on the ship, to prevent the boat from lurching forward when it leaves the water.

All being ready on deck and in the boat, stand by and wait for relatively steady conditions. Then (1) if at the davits, hook forward, then aft, haul taut, and hoist away as the ship rolls toward the boat, hoisting the boat quickly and steadily; (2) if at the boom, hook the sling ring on the boom fall hook by a pull on the tripping line from on deck, start the winch as the ship rolls toward the boat, and hoist the boat quickly and steadily.

Frapping lines, lizards, and steadying lines should be tended and the boathooks used as in lowering to keep the boat from sheering into the sides.

6A9. Elements of power boat handling. The following elements enter into the handling of a single-screw power boat.

Figure 6-9. Backing rapidly, rudder hard left.
Figure 6-9. Backing rapidly, rudder hard left.

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Figure 6-10. Boat backing rapidly, rudder hard right.
Figure 6-10. Boat backing rapidly, rudder hard right.

  1. Rudder. When the propeller is stopped and the boat is making way through the water, the bow will swing to the right when the rudder is placed right, and vice versa. This is due to the pressure of the water on the forward face of the rudder, which tends to push the stern away from the side toward which the rudder is swung and to cause the bow to swing opposite. The verse effect is noted,k but to a lesser degree, when going astern.

  2. Screw current. When the propeller turns over going ahead, it takes water from ahead of the propeller and expels it astern. In backing, the direction of this current is reversed. The water expelled by the screw travels about parallel to the line of the keel and strikes the rudder diagonally if the rudder is over. When the rudder is amidships and the propeller going ahead, the combined effect of the upper and lower halves of this rotary screw current has a tendency to cause the bow to swing starboard as the speed increases. When the rudder is amidships and the boat and propeller backing, the effect of this screw current causes the stern to swing to port.

  3. Sidewise pressure of the blades of the screw. As the blades turn, they exert a force which tends to push the stern away from the side toward which they are moving.The upper blades exert a force which is opposite in direction to the lower blades. But the lower blades are moving in greater water pressure, so the force of the lower blades is the greater, and in going ahead, the stern tends to starboard. In going astern, this same effect causes the stern to tend to port. A right-handed propeller is assumed, that is, one which turns clockwise when viewed from aft and going ahead.

  4. Wake current. The wake current is caused by friction between the hull of the boat and the water in going ahead. It is a surface current and is maximum in velocity and volume directly under the stern. It affects steering only when the boat is going ahead as follows:

Figure 6-11. Boat going ahead, screw going astern, rudder amidships.
Figure 6-11. Boat going ahead, screw going astern, rudder amidships.

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Figure 6-12. Boat going ahead, screw going astern, rudder hard right as screw is reversed.
Figure 6-12. Boat going ahead, screw going astern, rudder hard right as screw is reversed.

    1. It decreases the efficiency of the rudder.

    2. It increases the resistance offered by the water to the upper blades. Therefore, it decreases the advantage the lower blades gain by being in water of greater pressure.
We will now consider four cases that show how these factors affect the maneuvering of power boats.

6A10. Boat and screw going ahead. When the boat is dead in the water and the propeller starts turning ahead, the screw current hits the rudder and causes the boat to turn the way the rudder is put over. As the boat gathers way, the effect of this screw current diminishes. The normal steering effect of the rudder then controls the boat's head.

When the boat is proceeding ahead in the normal manner and the rudder is suddenly put over to one side or other, the boat will first fall off away from the side on which it is desired to go. The stern goes away most, but the whole boat is thrown more or less to this side. The boat advances along the line of the original course two or three boat lengths before she commences to gain in the desired direction. In this case, the speed of the boat has little effect on the amount the boat advances, but the more speed, the faster the turn will be executed. So if, by this method, you attempt to avoid a danger suddenly discovered two or three boat lengths ahead, you will probably fail. Of course, if you wish to avoid a moving object while making considerable speed, the time of turning may be to your advantage.

The greatest turning effect in going ahead is when the screw is turning over slowly.

6A11. Boat and screw going astern. In this case, maneuvering is more complicated because the effect of the propeller is as important as that of the rudder.

Four distinct forces are involved in the steering of a boat when backing:

  1. The discharge current from the propeller. This tends to throw the stern to port.

Figure 6-13. Boat going ahead, screw going astern, rudder hard left as screw is reversed.
Figure 6-13. Boat going ahead, screw going astern, rudder hard left as screw is reversed.

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Figure 6-14. Boat going astern, screw going ahead, rudder amidships.
Figure 6-14. Boat going astern, screw going ahead, rudder amidships.

  1. The suction current caused by the propeller drawing in water from astern of the propeller. This merely increases the normal steering effect of the rudder. It is not effective when the rudder is amidships.

  2. The sidewise pressure of the blades which forces the stern to port.

  3. The normal steering effect of the rudder.

When the boat first starts to back, the steering effect of the rudder is negligible. The suction current tends to force the stern to the side on which the rudder is placed. The propeller discharge and sidewise pressure both force the stern to port. Even with a hard right rudder the boat will usually back to port, because the suction current force is less than the combined effect of the propeller discharge and sidewise pressure from the blades (see Figure 6-8).

As the boat gathers sternway, the steering effect of the rudder increases. All four of the above forces combine to make the stern go rapidly to port if the rudder is hard left (see Figure 6-9).

Usually, after the boat is moving rapidly astern, it will be possible to steer the stern to starboard if the rudder is put hard right (see Figure 6-10). In this case, the combined force of the suction current and the steering effect overcomes the combined effect of the sidewise pressure of the blades and the discharge current of the propeller.

In spite of all that can be done, the boat will almost invariably back into the wind. The wind has less effect as the speed astern is reduced.

We may then summarize:

When the boat first begins to back, the stern will go to port regardless of the position of the rudder. As the boat gathers sternway, and the rudder is put hard right, the stern will usually swing to starboard, but if the rudder is put left, the stern will go rapidly to port. The stern will back into the wind under all conditions except when the speed of the boat is very slow or the wind is quite light.

Figure 6-15. Boat going astern, screw going ahead, rudder hard right.
Figure 6-15. Boat going astern, screw going ahead, rudder hard right.

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Figure 6-16. Boat going astern, screw going ahead, rudder hard left.
Figure 6-16. Boat going astern, screw going ahead, rudder hard left.

6A12. Boat going ahead, screw going astern. The same four forces affect the steering: (1) the discharge current of the propeller; (2) the suction current; (3) the sidewise pressure of the blades; and (4) the normal steering effect of the rudder. This is, in many respects the most important case, for it is the usual condition when danger is discovered suddenly close aboard. It is assumed by those who have not studied the question that the rudder will continue to affect the boat's head in the usual way as long as the boat has headway, even though the propeller is gradually reducing speed. This is not the case. New forces are brought into operation the instant the screw starts backing.

If the rudder is left amidships, the head will fall off to starboard and the boat will gain to the right as it loses way. This is because the sidewise pressure of the blades and the discharge current from the propeller are the only forces affecting the stern and both are forcing the stern to port (see Figure 6-11).

If the rudder is put hard right at the instant the propeller backs, the boat will change course to starboard (stern swings to port) at first. The bow may continue going to the right but usually it will stop, then slowly swing to port, the stern swinging to starboard (see Figure 6-12).

If the rudder is put hard left at the instant the propeller backs, the boat's head may go slightly to port at first, but as the speed decreases it will fall off rapidly to starboard, since all forces tend to swing the stern to starboard see (Figure 6-13).

The greatest turning effect of the screw in backing is when the screw is going astern fast.

6A13. Boat going astern, screw going ahead. In this case, the following forces influence the steering of the ship: (1) the discharge current from the propeller, part of which acts inboard on the rudderpost, forcing the stern to port; (2) the sidewise pressure of the blades; and (3) the direct steering effect of the rudder.

Figure 6-17. Using a boat line in lying alongside a gangway.
Figure 6-17. Using a boat line in lying alongside a gangway.

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If the rudder is amidships, the sidewise pressure of the blades and the discharge current striking the rudderpost counterbalance each other, and it is impossible to predict which force will be the stronger (see Figure 6-14).

If the rudder is put hard right, the discharge current opposes and greatly exceeds the forces of the steering effect and sidewise pressure. The stern goes off to port rapidly (see Figure 6-15).

If the rudder is put hard left, part of the discharge current that strikes the rudderpost and the steering effect are overcome by the other component of the discharge current and the sidewise pressure. The stern then swings rapidly to starboard (see Figure 6-16).

Throughout this discussion, a single-screw boat with a right-handed propeller is assumed. The twin-screw arrangement presents quite a different problem and will not be discussed. It must be remembered that it is possible for a boat not to act as described here. Differences in trim, wind, sea, tide, size of rudder and propeller, etc., all produce new forces or modify existing forces. However, if the cases shown are thoroughly understood, it will greatly simplify the estimation of the effect of outside forces.

6A14. Notes on power boats. In making a landing, it is a common mistake to keep too much headway on and rely on backing the engines full speed to stop the boat. This is poor seamanship, as the engine may fail to back promptly, causing a collision or smash-up. Therefore, landings should be made at low speed. Sudden reversals and hard backing put excessive strains on the engines and reversing gear, and will eventually result in breakdowns.

In coming alongside a gangway in a strong current, the tide should not be allowed to catch the boat on either bow. If it catches the boat on the inboard bow, it will sweep the boat away from the gangway; whereas, if the tide catches the boat on the outboard bow, it may sweep the boat underneath the gangway. The boat line from the deck forward should in all cases be used (see Figure 6-17), the boat being kept off a little from the side until it is fast, and then sheered in by the rudder. A boat may lie alongside with safety in a strong current on a line from the inner bow and with the rudder slightly over for sheering out.

When running in a seaway, speed should be reduced somewhat, not only to avoid shipping seas but to reduce the strain on the machinery due to the racing of the screw. In running into a sea, it is possible by careful nursing to make fair speed, watching the seas and slowing or even stopping for a moment as heavy seas are seen bearing down upon the boat. In running more or less across the sea, it is well to head up momentarily for a heavy wave. A lantern, filled and trimmed, should always be in the be in the boat, and a boat should never leave the ship for a trip of any great length without a compass. Weather is liable to thicken at any time, and a boat without a compass would have difficulty in reaching a landing or returning to the ship. For this reason, boat officers and coxswains should at all times know the compass course between ship and landing, and if they are away from they are away from the ship and it begins to thicken, they should at once observe the compass course before the ship is shut in.

If caught in a gale in an open boat, a sea anchor should be rigged by lashing spars, sails, or other suitable material together. A span should be fitted to this and the boat allowed to ride by the bow painter. If there is oil in the boat, a bag of it may be secured to the sea anchor.

6A15. Handling a power boat in surf. One of the most dangerous duties which a boat may be called upon to perform is landing through a surf. Special training and study are necessary in order to make the landing safely.

From seaward, surf always appears less dangerous and less severe than it actually is. Never make the mistake of underestimating the danger, and remember that is safer to overestimate the severity of the surf than to underestimate it.

The most dangerous place in the surf is the area from where the crest of the wave starts to topple over to a point some distance farther up the beach, depending chiefly on whether the beach is flat or steep. For this reason, as you approach the beach study it carefully to determine whether the place where the waves are breaking is steep and rocky or flat.

On a flat beach, the waves break well out from the shore, and after a boat has passed through this toppling area, it is in fairly safe waters. On a steep beach, the waves may break so close in to the shore that the bow of the boat in grounded while the stern remains in the breakers. Obviously such a situation is very dangerous indeed.

In landing through a surf, the greatest danger is that of broaching to, an action in which the boat pivots on its bow, swings broadside to the breakers, and capsizes. If the stern can be kept at right angles

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Figure 6-18. Navy type stock anchor.
Figure 6-18. Navy type stock anchor.

to the breakers, the danger of broaching to is materially reduced. One method of keeping the stern in the correct position is by towing a heavy drag over the stern. A better method is by using two anchors in tandem on a single anchor line. The first of the anchors is a heavy anchor separated from a lighter anchor by 10 fathoms of line. Northill anchors (see Section 6B5) should be used if possible.

Safest procedure for landing through a surf is to proceed in smartly and drop one anchor 5 or 6 boat lengths before reaching the breakers. Drop the second anchor as soon as the line connecting it to the first anchor has run out. Keep the anchor line taut and pay out the line as the boat takes it. The line should be not more than lightly snubbed until the boat grounds on the beach.

As the boat reaches the breakers, judge its position carefully and try to time the boat so that it follows directly behind a breaking wave. If this is not possible, do not hesitate but go right on in. As the boat follows the breakers, keep the anchor line taut and exercise care to keep the stern at right angles to the breakers. If the anchor line is properly handled, the boat will not broach to.

When the boat grounds on the beach, secure the anchor line. If the beach is steep, keep the engine and propeller going and use the rudder to help keep square on the beach. If the beach is flat, disengage the clutch to keep the propeller from being damaged.

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Figure 6-19. Stock anchor on bottom and biting.
Figure 6-19. Stock anchor on bottom and biting.

B. Ground Tackle

6B1. Introduction. Ground tackle is the name given to the equipment, considered collectively, used in connection with anchoring. It includes:

  1. All anchors.

  2. Chain, wire rope cables, or cable composed of both chain and wire rope for use with ships' anchors.

  3. Chain cable appendages consisting of connecting shackles, bending shackles, mooring swivels and shackles, gear and tools used on shackles, clear-hawse pendants, dip ropes, shackle tool sets, chain stoppers, wrenches for chain stoppers, and bending shots for various special anchors.

6B2. Types of anchors. At present, five types of anchors are used by the Navy. They are:

  1. Navy type, or old-fashioned anchors which have stocks.

  2. Stockless, or patent anchors.

  3. Short-shank stockless anchors.

  4. Special light-weight anchors.

  5. Mushroom anchors.

6B3. The old-fashioned anchor. The old-fashioned anchor, or stock anchor, is still in use, although it has been replaced to a great degree by stockless anchors. Since the corresponding parts of all types of anchors have the same names, and because the stock anchor has all the parts that the others have, with some additional, its nomenclature is indicated in Figure 6-18.

  1. Ring (shackle, or jew's harp): the ring to which the cable is bent. It is at the top of the anchor and is attached to the shank by a riveted pin.

  2. Stock: the cross arm just below the ring.

  3. Shank: a bar, vertical when the anchor is suspended by the jew's harp. The stock runs through the shank in a direction at right angles to the lower section of the anchor, the shank and the lower section being built in one piece.

  4. Crown: the rounded part of the anchor at the lower end, directly below the shank.

  5. Arms: the pieces extending from each side of the crown.

  6. Throat: the upper curved part of the arm, where it joins the shank.

  7. Palm or fluke: a broad, shield-shaped piece attached to the top of each arm; the holding or biting surface of the anchor.

  8. Blade: the part of the arm beneath the fluke.

  9. Bill or pea: the part of the arm beyond the fluke.

When a stock anchor first comes to rest on the bottom, is assumes the position shown in Figure 6-19,

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Figure 6-20. Patent anchors.
Figure 6-20. Patent anchors.

with the arms parallel to the bottom and with the shank supported at an angle by the stock. In this position, any pull on the anchor chain results in tipping the anchor until the stock is more or less parallel to the bottom and the arms perpendicular with one fluke pointed fair for biting. Further drag on the chain forces the fluke into the bottom, the heavier the pull, the farther the fluke digs in. As compared to a patent anchor of a given weight, a stock anchor has the greater holding power by far.

Stock anchors are stowed horizontally on platforms near the bow called billboards. In some cases, they are merely lashed to the weather deck in the eyes of the ship. TO get an anchor on the billboard requires catting and fishing. Catting consists of getting the anchor to the hoisting davit, or cat head, which plumbs the billboard; fishing consists of placing it on the billboard. The main disadvantage of the stock anchor lies in the difficulty involved in this type of stowage especially in the case of the larger anchors.

6B4. Stockless anchors. Patent or stockless anchors are of numerous makes, but the Navy uses chiefly the Dunn and Baldt. The distinguishing features of stockless anchors may be determined by referring to

Figure 6-21. Danforth, Northill and mushroom anchors.
Figure 6-21. Danforth, Northill and mushroom anchors.

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Figure 6-20. A patent anchor differs from a stock anchor mainly in that the patent anchor has no stock; its flukes are long and almost at right angles to the arms in the same plane as the shank. The unit consisting of the arms, crown, and flukes, is pivoted on the shank so that it can swing from 30° to 40° on either side. It should also be noted that the crown has projecting shoulders which catch on the bottom and force the anchor to take hold by throwing the flukes downward as the force of the drag exerts itself, both flukes biting. Generally speaking, a longer scope of chain must be used with the stockless anchor than with the stock type to insure holding, due to the fact that an upward pull on the ring has a tendency to "break out" the flukes, whereas on the stock anchor, this pull drives the flukes in deeper.

Patent anchors will ball easily in mud bottom and drag as a result of this mud coating. The stock anchor will pull slightly through the mud and bury itself deeper if there is sufficient scope; otherwise, the shank has a tendency to lift. In this case, the Baldt or Dunn anchor tends to roll the flukes out of the bottom, and the stock anchor to break out in a series of jumps.

Patents anchors possess a great advantage over the stock type in convenience of stowage. Since these anchors have no stock, they are handily stowed in the hawsepipes, and it is only necessary to continue hoisting until the shank is drawn into the housing, its flukes lying against the side. This does away with the lengthy and sometimes dangerous catting and fishing. The absence of a stock makes them less liable to fouling when in use.

Short-shank stockless anchors are ordinary patent anchors with a shank which is shorter than normal. They are used on ships whose design does not permit a long hawsepipe.

6B5. Light-weight anchors. Special light-weight anchors have come into use to an increasing degree, largely in connection with aircraft, landing craft and subchasers. The Danforth anchor (see Figure 6-21) is thus far the most widely used type of light-weight anchor for surface craft. It has extremely long, sharp flukes and an anti-rolling rod extending through the crown. It is claimed that this anchor has 3 times the holding power of a stock type anchor of similar weight and about 10 times that of the Baldt or Dunn anchors. Danforth anchors have been cast up to 3000 pounds for use as stern anchors on LST's. The Northill, which is a folding type of anchor, is carried aboard all aircraft which land on the water, and is extremely light, with large fluke areas.

6B6. Mushroom anchors. Mushroom anchors are metal weights, shaped like a mushroom and built with a shank. The rounded part, or crown, strikes the bottom first and the upper surface of the mushroom is cupped to provide a biting surface. The shank projections form the center of the cupped side (see Figure 6-21). This type of anchor is issued to submarines for anchoring while submerged, but is frequently used by them for all purposes due to its ease in handling.

6B7. Anchors carried aboard ship. A ship may carry bower, stream, stern, kedge, and boat anchors. These names are derived from the position or use of the anchor and apply regardless of the type.

Bower anchors are carried in the bow and are used for all anchoring except in special circumstances. The newer, large ships carry two; thus, starboard bower and port bower.

Stream anchors are anchors of medium weight wherever stowed and for miscellaneous use.

Stern anchors are anchors carried at the stern, regardless of weight or purpose.

Kedges are small anchors, usually of the stock type, the heaviest of which does not weigh more than a ton. They are intended for kedging, that is, moving a ship ahead a small distance at a time, by taking one of the anchors out in a boat, letting it go, and then hauling the ship up to it. If this is done to change the heading of the ship, as by hauling the stern around, it is called warping.

Boat anchors are small stock anchors for use in boats.

Anchors are usually made of cast steel; the fittings and the shanks for housing anchors, of forged steel. They vary in weight from wherry anchors that weight 30 pounds, to those carried by our newest battleships weighing 35,000 pounds. Anchors have their weight stamped on them near the base; a Bureau of Ships serial number and the date of manufacture are stamped near the top.

6B8. Anchor cables. Anchor chains are usually made up of 15-fathom lengths called shots connected by shackles. Standard cables vary in length form 105 fathoms for destroyers to 170 fathoms for larger ships. The chain is of the cast steel, or die-lock type, except where old issue wrought iron or forged mild steel is still in use.

The first shot, the one made fast to the anchor is called the bending shot, or outboard shot. It is usually heavier than the rest of the chain. It varies in length up to 5 fathoms and is referred to as the 5-fathom shot, or the outboard swivel shot. All succeeding shots are 15 fathoms in length. The bending

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Figure 6-22. Chain links.
Figure 6-22. Chain links.

shot contains a swivel and is limited in length to prevent the swivel from riding the wildcat when the anchor is housed, and to permit unshackling when mooring with two anchors or to a mooring buoy.

The links of a chain may be either open or stud (see Figure 6-22). The stud link gets it name from the cross piece at its center. Links are further subdivided into: (1) common links, which are standard, having the stud at the center; (2) enlarged links, which are spread more than common links; (3) end links, which have straight sides and are longer than ordinary links; and (4) the long end link, which has a stud near one end. Most ships have stud-link chains, although occasionally open-link chains with the links shorter than standard are used. This shorter link is called a close link.

In making up anchor chain, links are designated as follows (see Figures 6-22 and 6-23):

  1. A-links are common links.
  2. B-links are heavier than A-links.
  3. C-link is the long stud link.
  4. E-link is an open link.
  5. F-link is a special link for outboard shot.
  6. G-link is an open link and takes the bending shackle.

The size of the chain is designated by the diameter of the metal from which the common links are made. This dimension is called the wire diameter. In the U.S. Navy, the standard sizes range from 1/2 inch to 31/2 inches, the variance between successive sizes being 1/16 inch. Standard links are 6 times as long as their wire diameter, except that some of those still in use comply with the old standard and are 5.7 times as long as their wire diameter.

6B9. Shackles and swivels. Shots of chain are joined by some form of connecting shackles. They may be (1) U-shaped shackles, (2) bending shackles, (3) Kenter shackles, or (4) detachable links.

The U-shaped shackle was the old standard. It is a piece of steel forged in a U-shape with a hole in each of the flattened ends. To connect two shots, the shackle is first passed through an enlarged end link on the shot nearest the anchor, that is, bowed part outboard. The U-opening is next closed through the end link of the other shot by passing a bolt through the flattened ends of the shackle.

Bending shackles are used for connecting the chain to the anchor. They are shaped like U-shackles, but are larger. They are bent on with the open end forward instead of aft, as was the case of the U-shackles. The pin projects through one side of the shackle and is secured by a keying forelock pin.

Kenter shackles are pictured in Figure 6-24. The T-neck and T-slots of each of the two parts are fitted together through the links which are to be joined, and are locked in place by the stud and a tapered locking pin. The stud has shoulders which hook over projections on each half of the shackle and hold the two together. The tapered locking pin is then passed diagonally through both halves of the shackle and through the stud, thus combining the whole as a unit. A Kenter shackle can be made so that it is of approximately the same size and shape as any other link of a stud-link chain. This permits the chain to ride more smoothly over the wildcat, eliminates the need for the enlarged end links, and since there are no projections, does away with loss of anchors caused by the opening of the U-shackles, which may spread due to fouling on deck fittings or projections in the hawsepipe.

Figure 6-23. Make-up of anchor chain.
Figure 6-23. Make-up of anchor chain.

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Figure 6-24. Kenter shackle and detachable link.
Figure 6-24. Kenter shackle and detachable link.

Detachable links are based on the same principle as that of Kenter shackles, and they have replaced the Kenter shackles in most cases. A detachable link has a C-shaped part, comprising about 3/4 of the link. Projecting into the C-opening, from each side of the part, are ends which look like the upper part of a bolt with a circular head. The coupling plates slot over these projections, fill the C-opening, and form the stud which fits a pocket n the closed side of the C-part. The two parts are held together by a tapered pin which is locked at the large end by a lead plug.

Swivels (see Figure 6-25) are appendages which allow a section of chain to revolve without twisting, although one end of the chain is fixed. A swivel is included near the inboard end of the outboard swivel shot. When the ship swings about the anchor, the small fitting revolves on the rivet-shaped bolt, which projects into the oval part. In this way, the chain is prevented from twisting.

A mooring swivel accomplishes the same purpose, but is heavier and has two connecting links at each end. The chains of two anchors may be connected to the outboard (eye) end of it when mooring.

6B10. Chain markings. To aid in judging the amount of anchor chain which has run out, distinctive markings are usually placed on a chain at intervals of 15 fathoms. Although the type of markings may vary slightly on different ships, the following is the system commonly used:

  1. At 20 fathoms (the 5-fathom bending shot and the first 15-fathom shot puts a shackle at 20 fathoms), the first studded link on each side of the shackle has a turn of wire around its stud and is painted white.

  2. At 35 fathoms (20+15), the second studded link on each side of the shackle has 2 turns of wire around its stud and the 2 links on either side are painted white.

  3. At 5o fathoms (35+15), the third studded link on each side of the shackle has 3 turns of wire and the 3 links on either side of the shackle are painted white; etc.

This system of wire and white paint marking is supplemented by color systems employed variously on individual ships. Usually the shackles joining the shots are painted with different colors. Sometimes two colors are used alternately, or three colors may be used, and again a wide range of colors may be used with each shackle having a distinctive color. Also the links of the last shot (or last two shots) before the bitter end may all be painted a certain color as a warning mark. Color systems are adopted for a purpose, and it is important in handling ground tackle to know the color meaning of the system in use.

6B11. Chain stoppers. Riding chain stoppers and housing chain stoppers consist of a turnbuckle inserted in a short section of chain, a slip hook or pelican hook attached to one end of the chain, and a shackle at the other (see Figure 6-26). The stopper is secured by the shackle to a permanent pad on the vessel's deck. When in use, it is attached to the anchor chain of the ship by straddling a link with the tongue and strongback of the pelican hook.

The purposes for which chain stoppers may be used are as follows:

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Figure 6-25. Swivels.
Figure 6-25. Swivels.

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Figure 6-26. Chain stopper.
Figure 6-26. Chain stopper.

  1. To ride to when at anchor, in addition to the use of the brakeband on the windlass.

  2. For letting go the anchor more quickly than can be done by the brakeband when vessels are moving in formation.

  3. As an emergency fitting in case the brakeband of the windlass should get out of order.

  4. To hold a chain cable from running out, while it is being taken off the wildcat, to permit another cable to be put on for heaving in.

  5. To hold the anchors taut in the hawsepipes when housed.

  6. To hold an anchor chain when disconnected for the purpose of attaching the mooring swivel.

Depending upon the type of ship either 1, 2, or 3 stoppers are fitted in the way of each chain cable. Chain stoppers on all vessels but destroyers have strength equal to 40 percent of the chain cable in use. Hence, when used to ride by, all available stoppers, generally speaking, should take hold of the cable and care should always be used in seeing that the strain on all chain stoppers is equalized. They should not

Figure 6-27. Adjusting tension on a chain stopper.
Figure 6-27. Adjusting tension on a chain stopper.

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Figure 6-28. Anchor windlass.
Figure 6-28. Anchor windlass.

be relied upon solely for holding the anchor. The windlass brakebands should first be set up hard, then the chain stoppers attached and their turnbuckles tightened. The wildcat should then be disconnected from the engine.

6B12. Stress in chain. When coming to anchor, excessive strains on the anchor chain should be avoided. The practice of reducing the ship's headway by means of her ground tackle may introduce strains sufficient to fracture the links and will, in any event, be very apt to strain the chain beyond its safe service working load. The force necessary to stop a ship displacing 27,000 tons, traveling at 4 knots, in 100 feet is 429,000 pounds. If the ship is moving at 6 knots, the force necessary to stop her in 100 feet is 965,000

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Figure 6-29. Standing by to let go.
Figure 6-29. Standing by to let go.

pounds. To stop the ship traveling at 4 knots in 50 feet requires a force of 858,000 pounds, which is, of course, greatly in excess of the strength of the anchor chain.

SCOPES OF CHAIN

Depth in fathoms (outboard lip of hawsepipe to bottom) 5 71/2 10 15 20 25 30 35 40 45
Wrought iron chain (fathoms) 54 66 76 93 107 120 130 140 149 157
Cast-steel chain (fathoms) 64 78 91 110 127 142 155 166 178 188
Die-lock nickel steel chain (fathoms) 78 95 109 133 154 174 188 202 216 228

The scopes of chain indicated in the preceding table apply substantially, regardless of the size of the ship, provided the ship is furnished with a properly balanced outfit of ground tackle, and should not be exceeded except in cases of emergency. The scopes given are optimum scopes. If longer scopes are used, the chain may be strained beyond its safe service working load; if shorter scopes are used, the anchor will tend to drag before developing the full safe load on the chain. If greater holding power than that given by the anchor with the scope shown in the table is necessary, it is better practice to drop a second anchor, even with moderate scope, than to rely on the one anchor with a longer scope. In extreme necessity, when the greatest holding power is necessary, all anchors should be dropped and the chain veered the greatest possible scope, although if there is ample sea room, it would be better to reduce the scope to the amount shown in the table and accept the possibility of dragging anchor, rather than risk breaking the chain.

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6B13. Care of ground tackle. Anchors, chains, and moorings should be kept in good condition by the ship's force. The chain cables should be overhauled whenever necessary and precautions taken to insure that the various shots are properly marked and in good order. As the chain comes in when getting underway, each link should be examined for cracks in the weld and for other defects. Two competent observers, preferably petty officers of the artificer branch, should be detailed to examine the chain.

Once each quarter, and more often if necessary, all anchor cables in size up to and including 11/2 inches shall be ranged on deck and examined throughout their entire length. If necessary, they should be scaled, cleaned of rust and other foreign matter. Shackle bolts, locking pins, and swivels should be carefully examined and put in order, and such parts as require it coated with special black chain paint furnished vessels for this purpose.

Chain of sizes in excess of 11/2 inches should be overhauled, wire-brushed, and placed in a good state of preservation as often as routine inspections indicate is necessary. At least once each 18 months, all anchor chain cable, regardless of size, including shackles and shackle pins, shall be examined, overhauled, and placed in a good state of preservation. To distribute the wear uniformly throughout the entire length of the cable, the shots should be shifted to new positions as necessary.

To prevent fractures resulting from the dropping of the G-link on the jew's sharp, a hardwood block should be securely seized in place in the bending shackle between the lower end of the open G-link and the crown of the jew's harp. This block should be renewed every time the anchor is made ready for letting go.

6B14. Handling ground tackle. Anchor chain and anchors are hove in by means of an anchor windlass (See Figure 6-28). That part of the windlass above decks which engages the chain is known as the wildcat. It is a circular member with a toothlike arrangement around its circumference which engages the links of chain as it revolves around its vertical axis. It is fitted to a vertical shaft which is connected to a motor or engine below decks, and may be either rigidly locked to the shaft or left free to rotate independently. Beneath the wildcat is a braking surface against which a friction band may be set up to create a braking effect. Some newer windlasses have magnetic brakes on the motor s well as a friction brake on the wildcat. Above the wildcat, or set off to one side and connected by gears, there may be a concave metal barrel called a capstan. This too, operates free or on the shaft. It is used for handling heavy weights, mooring lines, etc.

The windlass may be powered by steam engine, or more frequently by an electric motor, or a hydraulic motor located below decks and controlled from the weather deck in the vicinity of the wildcat. Recently on smaller ships, windlasses powered by electricity in which the wildcat and the motor are a self-contained unit, have been installed. The trend on larger ships has been toward the hydraulic type.

As the chain comes aboard through the hawsepipe, it passes along the deck over flash plates (on large ships) over the wildcat and down through the chain pipes into the chain locker. The chain goes into a bin, and its bitter end is rove through a ring bolt at the bottom of this bin and secured to a pad eye on the upper part of the bulkhead by a pelican hook. Another method of securing the bitter end of the anchor chain in the chain locker is by means of a shackle so weakened as to carry away when subjected to a strain beyond a certain number of pounds. This is to prevent damage to structural members of the ship in case the chain gets beyond control.

6B15. Letting go. Preparatory to anchoring, all but one of the stoppers are slipped, the brake is released so that the anchor is supported by the remaining stopper, and if there is a long space between the anchor and the wildcat, a few links of the cable are roused up on deck. If the ship is anchoring in deep water the anchor may be walked out slowly by the engine. An order is given to stand clear of the chains and it is very important that this order be obeyed, because practically nothing will stop an anchor cable which parts, or whips, and there is a possibility that everything on the forecastle may be wiped clean. On the command to "Stand by," before letting go, the toggle is taken out of the pelican hook and a man stands by with a top maul. On the order "Let go," the bale shackle is knocked off the pelican hook with a top maul, the pelican hook opens, and the anchor chain is released. If necessary, the anchor is given a start. It is frequently necessary to give old-fashioned anchors a start, as they rest on the billboard and do not exert as much pull on the chain as an anchor which is suspended by a stopper. They are released by tripping a trigger on a retaining tumbler.

As the chain runs out, the amount, strain, and its angle relative to the bow are reported, such as, "Thirty fathoms on deck, Sir," "No strain," "Chain tending slightly aft," etc. (Tend is used with chain,

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Figure 6-30. Weighing anchor.
Figure 6-30. Weighing anchor.

as a verb, to state the direction of the chain relative to the bow.) The amount of cable payed out should be based on the scopes tabulated on page 115. One anchor with a long scope of chain has better holding qualities than two anchors with half as much chain, because a short scope causes a pull on the anchor that may loosen the flukes.

As a rule, a small anchor buoy is attached to the crown of each anchor by a light line. An anchor buoy indicates the actual position of the anchor to which it is attached by floating above it. Each buoy is usually painted a distinctive color, such as green for starboard anchor, and red for port anchor. If an anchor buoy floats on the surface, it is said to be watching. An anchor buoy may fail to watch because its line is too short, or is fouled in the chain, or because the buoy itself is waterlogged.

Before anchoring, the line which attaches the buoy to the anchor should be adjusted to a length which is a couple of fathoms greater than the depth of water at the anchorage. This extra length is to allow for slight fouling and for the fact that variation of the tides, sinking of the anchor in mud, etc.,

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cause the actual depth to be greater than that shown on the chart. However, there should not be so much spare line on the anchor buoy that it will be permitted to drift to some distance from the actual position of the anchor. The expected depth of water of the anchorage may be secured from the navigator. The anchor buoy and line must be laid up along, and outboard of, the life lines. It should be put overboard, or streamed, well clear of the ship the instant the anchor is let go.

6B16. Weighing anchor. Prior to hoisting the anchor, the engine is warmed up, of of the steam type, and tested in any case. The wildcat is then engaged with the shaft, the brake released, a strain taken on the chain, and the stoppers cast loose. Before the time set for getting underway, and after the main engines have been tested, the anchor is usually hove in to short stay, a condition in which there is no more chain out than is necessary to keep from pulling the anchor loose from the bottom. Usually the amount of chain to be hove in is designated as, "Heave in to 10 fathoms."

When ready to get underway, the anchor is hove in as ordered from the bridge, and the amount of chain out is reported to the bridge from time to time. Orders may be given to heave in to any number of fathoms or to heave right up. In any case, report is usually made when markers are at the water's edge, "Fifteen fathoms at the water's edge, Sir," when the anchor is at "short stay," "up and down," "aweigh," "in sight," and "secured," or "ready for letting go." The anchor is "up and down" when the stock has been pulled up from the bottom, but the crown is still touching. The action of the chain signifies this condition of the anchor and it is judged either by the officer in charge of the forecastle or by the boatswain. Accompanying the report that the anchor is in sight, is a report regarding its condition; as, "Anchor in sight, Sir; clear (or foul) anchor."

The three elements of information to include in each report to the Commanding Officer when heaving in are: (1) amount of chain still out, (2) direction the chain or anchor tends (leads), (3) the strain on the chain. Thus these three elements, used together, would result in a report that might be as follows: "Thirty fathoms at the water's edge, chain tending on the port bow, moderate strain." The amount of chain can be measured "at the water's edge," "in the hawse," "on the windlass," etc. The direction is indicated as "ahead," "on the port or starboard bow," "on the port or starboard quarter," "aft," "under the forefoot," etc. The strain is indicated as: "no strain," "light strain," "moderate strain," "heavy strain," "breaking strain," etc.

As the chain comes in, a hose is played on it to remove all mud and other fouling. Also, the markings are usually repainted, the old mark having first been wiped. Each link is tested by striking it with a hammer. If a link rings, it is all right, but if it sounds flat, the first lieutenant or the boatswain should be notified immediately, although the flat sound may be caused by the link's touching something or by its being dirty. Care should be taken to remove all dirt from the chain. This cleaning helps to preserve the chain and keep dirt and odors out of the chain locker. Where the bottom is extremely muddy, it may be necessary to slow down the rate of heaving in; this slowing down is preferable to dirty chain.

6B17. Dragging. A ship may drag her anchor due to a swift tideway or current, bad weather, or the poor condition of the bottom for holding an anchor. To be safe, always consider that your ship might drag her anchor, and therefore you must keep an alert watch for the first signs of dragging. One means of detecting dragging is to put over a drift lead. A drift lead consists of a heavy lead, 30 to 50 pounds, secured to the end of a line. Enough hand leads to make up the necessary weight may be used if a heavy lead is not available. The drift lead line is not marked.

Place the lead on the bottom abreast of the bridge and close to the side of the ship. The line should be secured to the ship at a point about 30 to 50 feet (depending on the depth of water) forward of the bridge and thus have the line tending distinctly aft. If you observe that the line tends up and down or forward, this is a definite indication that the ship is dragging anchor. The drift lead should be taken up before a swing, and replaced immediately after the swing. A ship is particular liable to drag as the current starts to run after a swing, because the swing may loosen the anchor, and the growing current then "breaks it out."

Another means of detecting dragging is by observing the riding anchor chain. If the chain is observed or felt to be giving characteristic jumps (continually being taut, then easing momentarily, and again becoming taut with a jump), the anchor is dragging, and tremors can be felt by standing on the chain.

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A range may be used to check for dragging. A range consists of any two well-defined objects on shore that may be lined up. If you note that these two objects do not line up but are drawing apart (providing the ship is not swinging to a change of tide or wind), it is an indication that the ship is dragging. A range should always be checked from the same point on the ship. With two ranges, one near either beam, the difference between yawning or swinging and actual dragging is easily distinguished. This is not necessarily true of the drift lead, and the drift lead is then most useful as an additional precaution.

A more accurate method of checking for dragging is by a fix obtained by compass bearings of objects ashore as lighthouses, smokestacks, beacons, and other prominent and easily distinguished objects. Plotting a fix on the chart will immediately show whether the position of the ship is changing andn thus whether the anchor is dragging.

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