Romeo in the phonetic and .-. in Morse. No meaning in the International Code.

A fast-running stream or current, usually caused by the tide and occurring where the stream is constricted, either because a channel narrows or because it shoals. Eddies and Overfalls are commonly found in a race.

A small rectangular flag or burgee, formerly flown at the masthead to indicate that the boat was actually participating in a race, discontinued in 1976

A way of binding two ropes together (or Seizing them) by wind­ing the line between and round so as to make a number of figure-eight turns.

A radar beacon with a transponder, which detects a ship’s radar emission and responds to it by transmitting its own signal. (Please see Radar reflector and Ramark.)

A passive reflector of radar emissions, usually made of three plane surfaces meeting at right angles to each other. The result forms eight three­-sided funnels. Such reflectors are mounted on buoys and beacons so that ships equipped with radar can locate them. Any private craft, of whatever material of construction, should carry a radar reflector if she moves in waters where she may encounter ships. The reflector should be as large as feasible, and certainly not less than 15 inches, and preferably at least 18 inches, across the diagonal. The reflec­tor should be hung from three of its corners, so that one ‘funnel’ faces up to the sky as if to collect rain. That will leave six funnels to face outward around the horizon.

Two-way communication at sea is still commonly conducted using radios on medium frequency (MF), high frequency (HF), or very high frequency (VHF). VHF is most commonly used by private boat owners because it is cheaper and more compact than the other kinds – but its range is much less. In what is called simplex working both parties speak over the same channel, and you cannot receive while your ‘transmit’ button is pressed. Hence each party must say ‘over’ to signal to the other that he has fInished speaking and is ready to listen. Duplex operation works on two channels, and permits ordinary conversation without need for the ‘over’ drill. Single Side band (SSB) is capable of transmitting across oceans.

A fixed radio transmitter, (now rarely used) usually identifying itself by a Morse code signal, on which a bearing can be taken with a Radio direction-finder. Marine radio beacons are sited specifIcally to assist sea vessels, but a small-boat skip­per can also make use of aero beacons if they are sited near the coast. (But some aero beacons transmit on VHF, whereas marine beacons are usually in the low frequency band.)

Commonly known as RDF, and even more commonly as DF, this useful navigational aid is now rarely used. Lighthouse authorities would maintain transmitting beacons at well-chosen locations, anyone of which can be identifIed by its own call sign in Morse code. The receiver’s aerial is rotated until the reception reaches a minimum – the null point. When the signal is at a null, the aerial is pointing towards the station.

A small triangular or square sail set flying from the masthead in clippers and other big sailing craft.

To moor several boats side by side, all lying to the single anchor or mooring of one of them.

Very often called a Toe-rail nowadays, the rail is the piece that forms the deck edge. Not as high as a Bulwark, it may nonetheless have a capping piece. In the past it was made of timber, but nowadays it may be of angle-section aluminium alloy, with close-spaced holes which provide useful attachments for this and that. An undecked boat does not have a rail, but has a Gunwale. The railing that stops you falling off some decks is best called the Guard rail.

To raise the land, or a light, is to approach suffIciently near that it appears above the horizon.

Of a mast, is forward or aft inclination. If not specifIed, it will generally be aft. Used also as a verb, and of other parts of a boat too, notably the Transom.

A radar beacon that transmits a signal without need of being triggered by a ship’s emissions. (See also: Racon.)

(1) The alignment of two objects to give a Position line. Better known in England as a Transit.

Range (2) The difference in level between successive High and Low waters – in other words the amount the tide rises or falls on a particular day. The Rise of the tide is the amount that High water is above Chart datum, (See also: Height)

To layout an anchor cable or the like on deck or some such convenient place

Moving at 35 to 45 knots

Or rat’s tail, is a pointed end to a rope, made by removing strands. Seen at the termination of a Bolt rope on a sail, for example.

(1) The speed of a tidal stream or current is its rate. Usually given in knots. Rate(2) The daily amount by which a ship’s chronometer gains or loses. If the rate is consistent it is easy enough to make allowance.

Moving at 25 to 35 knots

The ‘handicapping’ of a racing yacht based on extensive measurements and the application of more than a few formulae to see ‘how she rates’.

A step formed between a pair of shrouds, and made of timber or rope. Ratlines form rungs and offer a way to the masthead, or at least to the Hounds. A fIne seaman-like term which may come in handy one day is to ‘rattle down’ the rigging. It means either that you fItted ratlines, or that you adjusted them for neatness and tautness.

Royal Cruising Club

European Recreational Craft Directive. A series of requirements for leisure boats under 24m LOA built in Europe since 1998. Divided into four categories (A-D) by intended sea area.

To sail with the wind abeam or forward of the beam. You may sail a close reach, but that is not so close to the wind as close-hauled. There is a noun from this word, as in, ‘We crossed the bay in a single reach’, meaning that the boat was on the wind the whole way, but did not have to tack. (See also: Beat and Board.)

A line, used to improve headsail shape on a reach. Taken from the clew of a headsail to a point further outboard and forward than an upwind sheet lead, to close the leech of the sail.

In effect a spreader to give a spinnaker guy a more effective angle when reaching. The inboard end of the strut is housed on the mast, the outboard bears on the guy. The same device is more often known as a jockey pole in the UK.

A helmsman’s warning to sheet-hands (and to the cook below) that he is going to tack, so headsail sheets must be trimmed, and the cook must brace both herself and the saucepan. After giving a few seconds’ warning the helmsman puts the helm down with the cry of ‘lee-oh’.

To make navigational calculations. The reckoning may be the task itself, but is more commonly the result, expressed as a position or perhaps a distance.

A tidal stream that runs in more or less a straight line, on flood and ebb. The other kind is Rotary.

Reduction Of soundings is to correct your depth readings to what they would have been if taken at Low water, the chart depths being those which obtain at that state of the tide.

A kind of Foghorn which uses a vibrating reed to make the sound. (Well, what did you expect?)

A knot for joining two ends of line together. Take one in each hand and wrap left over right, then right over left. If done wrong, you end up with a Granny knot, which is harder to undo.

To reduce sail area by rolling or folding part of the cloth – usually along the foot in mainsails and along the luff in headsails, though either form is found in either sail. The process of making a reef is commonly called ‘tucking-in a reef, even where roller-reefing is used and there is no actual tucking. The reverse procedure is ‘shaking out a reef, an expression that suits a condition where cloth has been bundled and crumpled up. A reef is in fact that area of a sail between the foot and a set of reef points, or between two sets of reef points. Hence the expression to ‘take in a reef. In times past the lowest reef was sometimes called the ‘slab’ and this term has been revived for the folding type of reef, where a pre-determined area of cloth is taken in (ie. jiffy and points). The Slab reef contrasts with the rolled reef where the amount of cloth accommodated on the boom is continuously variable and not in discreet steps. All types of slab reef make use of Cringles (eyes) on the luff and leech of the sail, and these are first hauled down to form the new tack and clew of the sail. It is then necessary to tidy up the excess cloth along the foot of the sail, which is known as the Bunt. Whether or not there is a boom, the bunt can be firmly held by short lengths of cord, called Pennants or Points, which pass through eyelets in the sail cloth. Alternatively, but no so conveniently a continuous length of line may be threaded through the eyelets and around the bunt. The modern jiffy reefing for boomed mainsails makes use of elastic cord, a length of which is permanently threaded through the reef eyelets from luff to leech. After the tack and clew cringles have been hauled down to the boom, bights of the shock cord are stretched down and tucked under hooks on each side of the boom.

Mechanical apparatus for roller reefing, either of a mainsail around its boom or of a headsail around its luff-spar or rod.

To pass a rope through a block or an eye in the same sense as ‘to thread’ a needle. Rove is the past tense, and participles.

The notional carrying capacity of a vessel used for port dues, taxation and so forth. National authorities calculate the figure by subtracting from the hull volume various allowances for crew’s quarters, navigation room, engine rooms, and so forth. Even small private yachts may have a register tonnage, which may be a bit of fun and may be written on forms by petty officials who ‘welcome’ you in this port or that. But for private craft the whole thing is a nonsense. The one thing you can say for sure about Register Tonnage, is that it is not a matter of weight.

A commercial ship is registered with her appropriate national authority (for example the Registrar of British Ships). The process takes note of her Register tonnage which is a basis for the calculation of harbour dues. Private craft maybe registered with national authorities (and in some countries they must be).

A non-stick coating applied to the inside of a mould so that the gel coat of a moulding (for example, a hull) will not stick to it. An owner is not normally concerned, but carelessness in preparing the mould may result in a need for force to extract the moulding, with the loss of some areas of gel coat. These scars must then be patched in, and if detectable may be an indication of the working standards of the builder.

To ease a rope through a Block or round a Samson post. The rope itself renders if it runs freely through a block, dead-eye or the like. Ashore one might say ‘runs freely’ where one would say ‘renders’ afloat.

The buoyancy provided by that part of the hull which is above the normal waterline and which can be immersed without flooding. An open boat with little Freeboard has less reserve buoyancy than a decked boat with cabin and watertight portholes.

Three main types used in boat building: Polyester resin is reinforced with glass fibres (Resinglass). An amateur can use polyester resin for repairs and odd jobs – just buy it and follow the instructions diligently. Epoxy resin is a first-class adhesive also available for DIY-ers, and no boat should be without a supply on board. Epoxy resin also forms the basis of good paints and surface treatments, as does Polyurethane, another synthetic resin.

A method of laminating a structure, such as a hull, whereby resin is forced into the dry mat or laminate material. Benefits include lower emissions and greater control of the resin-to-fibre ratio.

This is what you get when you draw a straight line between two points on a Mercator (ie. ordinary) chart. Unfortunately it is not in fact the shortest distance between two points because the chart shows a distorted picture of the face of the earth. The shortest distance would be a ‘Great circle’, and it would be a curved line on your chart. But for distances of less than 100 miles, the difference is negligible.

A form of rolling motion which is induced by the interaction of sail and sea forces acting in harmony. For example, when running, a sea-induced roll may cause the spinnaker to start swinging, and that may in turn augment the roll. Another cause is the shedding of air vortices from the trailing edges of a sail.

The ribs of a wooden boat are sometimes called Frames, usually if cut to shape, and sometimes called Timbers, usually if steamed to shape. You will appreciate that only wood of small scantlings is likely to be bent, so timbers are small and frames large.

l) A boat rides to her anchor. When anchored by night she must show an all-round white light (two in some cases) known as a Riding light. In ordinary English a boat will ‘ride out’ a storm, but that has nothing to do with being anchored, she can do it while hove-to, or with bare poles, and the implication is one of riding the seas. 2) A rope is said to ride on another when it crosses over and jams it. The most common use of the word is in connection with the sheet winches of modern sailing boats, when the loaded part rides over the hauling part and nips it tight, a situation known as a Riding turn.

A rope is said to ride on another when it crosses over and jams it. On a sheet winch, when the loaded part rides over the hauling part and nips it tight, this is a situation known as a Riding turn.

The general term for the arrangement of spars and sails on a boat, as in ‘cutter rig’. One also says of a boat that ‘she’s cutter-rigged’. But the spars, stays and sails themselves are not collectively ‘the rig’ in the sense that one might want to say, ‘We removed the rig and stored it under cover’. In fact that case you would have to say that you have ‘removed the spars, sails and rigging…’. The rigging includes the wire stays and shrouds and their associated rigging screws. Various common rigs are discussed under their own entries: Bermudan, Cat, Cutter, Gunter, Ketch, Lug, Schooner, Sloop and Yawl.

To assemble and fit the rigging and sails up to, but not including, the point when sails are raised.

The actual wires and ropes comprising the rig. They fall into two sets, the Standing rigging which sustains and steadies the mast, and the Running rigging which raises and controls the sails and movable spars.

A tensioning device of shrouds and the like. It has two eye-bolts threaded into opposite ends of a central body. One bolt is threaded left-handed and the other right-handed, so that when the body is turned the ends move simultaneously either in or out. (That’s to say they move in opposite directions.) Rigging screws are the norm on modern boats for tensioning the rigging. They are commonly called bottle screws, though small ones may be called turnbuckles.

Not a very good term in relation to sea rules. The Collision Regulations are phrased in terms of duty to ‘keep clear’ or to ‘give way’, rather than in terms of any rights.

A propeller which, when viewed from astern, rotates clock¬wise. (See also: Wheel effect.)

The force acting to bring a heeled yacht back to an upright position.

Pronounced ‘wriggle’ (with a bit more of the ‘o’ at the end though), it means a small waterway or water channel, of which there may be several on a boat. In particular it describes the Eyebrow or miniature eave which arcs above a Scuttle to keep drips of water out.

Royal Institute of Naval Architects

‘Rise of the tide’ is the amount by which High water on that day is above Chart datum. Technically ‘height’ may refer to any hour, whereas in the past ‘rise’ was the height just at High water.

Pressure change of 1.6 to 3.5 mb in the preceding three hours.

Pressure change of 3.6 to 6.0 mb in the preceding three hours.

Pressure change of 0.1 to 1.5 mb in the preceding three hours.

Pressure change of more than 6.0 mb in the preceding three hours.

A light fore-and-aft member in a wooden boat providing support for a Thwart or some other fitting. It is like a Stringer, fitted inside the timbers.

Royal National Lifeboat Institution

The outward and rearward curve of the leech of a mainsail, an unnatural shape which is maintained by Battens. Roach makes a pretty shape, and gives untaxed area to the racing man whose sail area is calculated on straight corner-to-corner measurements. Little aerodynamic advantage can be expected, except in fully-battened sails of high Aspect ratio where the sail can be given a markedly elliptical profile. In that case the resulting aerofoil can be very efficient for fast close-hauled sailing. Otherwise, one is better off without roach or battens.

Both or either mean the same thing – a sheltered place where boats can lie at anchor. ‘Roads’ is an alternative to road.

A rope-band or short length of rope for tying around a sail or the like. Sailor’s speech and sailors’ spelling have resulted in variants such as roban and robbin.

The fore-and-aft curve to the keel or bottom of a boat. A punt has no rocker, for example, her bottom being a straight line.

Not the signal rocket you may use in distress, but the line-carrying rocket which is fired from shore to ship, or ship to ship, usually as a preliminary to sending over a heavier stay for breeches-buoy rescue.

1) Noun. An anchor cable, especially one of rope rather than chain. It is also the rope that drags a trawl. Rode (2) As a verb (present or past participle) it describes the behaviour of a moored vessel under the influence of wind or tide. If she is lying head to wind, she is ‘wind-rode’. If she went aground when lying head to tide, she was ‘tide-rode’ at the time.

A coloured yarn embodied in the lay of a rope to identify either its composition or its ownership. Like the devices embodied in bank-notes, it was originally a deterrent to those rogues who sought to earn a little extra by selling government property from the dockyards.

Both verb and noun, describes the lateral movement of a vessel. The other principal motions of a boat are Pitch, Yaw, Heave, and Scend. (See Rhythmic rolling.)

A general term for jibs or headsails which can be rolled around their own Luffs, whether for reefing or just for furling. The first, using a wooden Luff spare turning on a wire threaded through its length, was introduced by Captain du Boulay in 1887. Modern versions of the same idea use an aluminium alloy spar. Both these kinds may be used for reefing – that’s to say with the sail partially deployed. The all-or-nothing furling gears have wire at the luff, as in the Wykeham Martin gear.

A system for reducing the area of a sail by rolling it around its luff, or sometimes foot, for reefing or stowing. Headsails are most usually found on roller furling gear, and mainsails can either be reefed in-mast, on gear mounted behind the mast or in-boom.

A knot used when the pull is to be along a spar or a rope.

A type of river-bank anchor. Its single fluke must be pressed home by the weight of your foot, and once in the ground it presents no danger to passing people or cattle. But such an anchor will not penetrate of its own accord, so it cannot be used for bottom anchoring.

The root of a pier or jetty is the shoreward end. The seaward extremity is the Head.

A sleeping berth made of canvas or the like. One edge of the canvas is attached to the ship’s side, and the other to a bar of wood or metal. In the daytime the whole is rolled up against the ship’s side, but for sleeping it is extended and the bar lodges in suitable supports in bulkheads or ports. (See also: Pipe cot)

A saucer-shaped copper washer which fits over a copper boatnail before it is riveted up tight. Also known as a rove or a ruff, though in the USA it is known as a Burr.

Lines, sheets, guys, ties, strings that can be of fibre or of wire. Rope is of various ‘constructions’, plaited, braided, or the ordinary laid (which means twisted). Furthermore, laid rope may be Hawser-laid, which means three strands twisted together in the usual manner, or Cable-laid, which consists of hawser-laid ropes twisted together. Cable-laid ropes are most commonly used for big hawsers, by the way, while hawser-laid ropes are used for sheets, halyards and the mooring lines of small craft.

Royal Ocean Racing Club.

A tidal stream that changes direction during the ebb or flood, or both, so as to swirl round in a large eddy. Such streams are found near promontories. Its contrary is called a Rectilinear stream.

This is a mast which is free to turn about its own axis, not in complete circles but from port to starboard. This means that a mast of stream-lined section can turn to present its best aspect to the wind on either tack, and when close-hauled or on a broad reach. The Finn dinghy is an obvious example as are many multihull designs

Wave height of 2.5 to 4m.

The conventional form of boat hull where the sides turn into the bottom in a curve. (See also: Bilge)

Colloquial term for racing round a buoyed course

One of the most widely used and useful of hitches. A double turn is even better.

To bring a boat’s head up to the wind.

Filaments of glassfibre, bundled loosely together to make a thicker string. These strings may be woven into a cloth which is known as Woven rovings, which can be used as reinforcement for polyester resin in hull construction. Although woven rovings is a very strong material, Chopped strand mat is often preferred because it is difficult to get woven rovings to absorb sufficient resin. A mixture of the two types of reinforcement can be very effective in certain cases.

The use of oars to propel a boat or ‘What you do when the wind drops or the outboard stops’.

Technically the rowlock is the hole into which the U-shaped metallic or plastic rowlock crutch drops, although the term rowlock crutch is very rarely used in leisure boating

A Wale, usually of timber fitted along the outside or bottom of a hull to protect it from wear. A rubbing strake should be fitted in a way that allows easy replacement when it is sufficiently battered.

The foil(s) used to steer a vessel. A rudder has a Blade, the part which acts on the water, and a Stock above it to transmit torque from Tiller or steering gear. The lower extremity of the blade is the Heel, and the upper extremity of the stock is the Head. A Lifting rudder has a pivoted blade that swings up to reduce its Draught. The blade is then fitted between Cheeks, which are in turn fitted to the stock. A rudder may be of several kinds, notably outboard or inboard. The transom-hung rudder is outboard and easily accessible: its hangings are the simple Pintle and Gudgeon. The inboard rudder’s stock passes through a trunk or tube, at the bottom of which there may be a watertight gland similar to that used with a propeller shaft. A Spade rudder stands in clear water, away from Keel or Skeg, an arrangement which may minimise drag but which leaves the rudder exposed to stray ropes, painters or plastic bags. A Balanced rudder is one which has some of its area ahead of the pivotal axis, thus reducing loads on the tiller. Something between ten and fifteen percent of the total blade area is enough to have ahead of the hinge line .

The colloquial term for that section of the Collision Regulations which is headed ‘Steering and Sailing Rules’.

A means of estimating the rise or fall of tide for each hour of the six. In the first hour the change is assumed to equal one-twelfth of the range: in the second hour two-twelfths; in the third and fourth hours three-twelfths each; in the fifth two, and in the sixth one.

1) The distance covered in a stated time. The ‘day’s run’ implies a 24-hour day, noon to noon.

Run (2) The after part of the underwater part of a hull. A pretty Buttock-line is always noticed by a sailing man.

To sail before the wind. To ‘run under bare poles’ is a heavy-weather tactic, all sails being furled and lashed down.

This is a small open motor boat capable of a fairly high speed – say 10-15 knots. If she were slower she would be a dinghy, if slower and a little bigger a launch, and if faster a sports boat.

Short for ‘running backstay’ (See also Backstay)

A noose made in a rope by making a bowline round the standing part. The noose is what a sailor would call a Bight, but a ‘bowline on a bight’ is not a slipknot like this – it is a bowline formed in a doubled rope. That’s to say the bight itself is formed into a bowline.

Sailing downwind with mainsail out to the windward side. Evidently there is every chance of a gybe in such a situation

A useful non-GPS navigational technique. Whereas the ordinary fix crosses Position lines taken from two or more objects as nearly simultaneously as possible, the running fix uses observations separated by an interval of time. One or more objects may be used to provide the position lines. The essential third item of knowledge is the distance and track made good between observations. For example, two position lines are obtained from a single wireless mast ashore at an interval of, say, ten minutes. If they are now drawn on the chart and the vessel’s track is drawn to scale, there can be only one position where it will fit between those lines. (The technique might equally be known as a ‘running fit’ and it may become clearer.) For success the boat must be steered on a constant heading and distance must be assessed as carefully as possible with allowance for stream, current and leeway due to the wind.

Navigation lights as prescribed for a vessel making way in the International regulations for Preventing Collisions at Sea

The rigging used to raise, lower and control sails – as opposed to standing rigging.

Royal Yachting Association