Parts of the boat
Know her, part by part
Rotate a 3D sloop and tap any part — hull, keel, rudder, mast, rigging, sails, deck hardware — to learn its name and what it does. The full parts-of-the-boat reference for RYA Competent Crew and Day Skipper. Drag to rotate, scroll to zoom, and tap any part of the 3D boat — or read the full reference below. Original artwork, RYA terminology.
Interactive 3D boat — the full parts list is below.
30 parts, grouped by where they live and what they do.
Hull & foils
The body in the water and the blades beneath it.
- Hull
- The watertight body of the boat — everything else floats on it. Its shape is the great compromise: fine forward to cut the waves, full amidships for stability and room, narrowing aft to leave a clean wake.
- Bow
- The front of the boat — the end that meets the sea first. A fine, flared bow knifes through chop and throws spray clear of the foredeck.
- Stern
- The back of the boat. Modern cruisers carry a broad, flat stern for form stability and a roomy cockpit; it also hangs the rudder and often a bathing platform.
- Keel
- The deep fin below the hull. It does two jobs at once: it resists the sideways slide a sail creates (so you can sail across and into the wind), and it carries ballast low down to keep the boat upright.
- Rudder
- The steering blade hung at the stern. Turn it and the passing water pushes the back of the boat sideways, swinging the bow the other way. It only bites while water flows over it — a stopped boat will not steer.
- Transom
- The flat athwartships face that closes the stern. It carries the boat’s name, often the rudder fittings, and on many cruisers folds down into a bathing platform.
Rig & spars
The mast and the wires that hold it up.
- Mast
- The vertical spar that holds the sails up. It stands not by its own strength but by the standing rigging pulling evenly on every side — slacken one wire and the whole rig is in danger.
- Boom
- The horizontal spar along the foot of the mainsail. It controls the sail’s lower edge and angle; it also swings across the cockpit in a tack or gybe — which is why “mind the boom” is the most repeated phrase afloat.
- Spreaders
- The horizontal struts partway up the mast that push the shrouds outboard. Widening the angle the shrouds make with the mast lets thin wires hold a tall spar — guy-ropes spread wide on a tent pole.
- Forestay
- The wire from the masthead to the bow. It stops the mast falling aft and gives the taut leading edge the headsail is set on.
- Backstay
- The wire from the masthead to the stern. It opposes the forestay, stopping the mast pitching forward; tensioned, it bends the mast to flatten the mainsail in a breeze.
- Shrouds
- The wires from the mast down to each side of the hull, over the spreaders. They stop the mast falling sideways — cap shrouds reach the masthead, lowers steady the middle of the spar.
Sails
The engine — cloth that turns wind into drive.
- Mainsail
- The principal driving sail, set behind the mast. Hoisted on its halyard, its foot tensioned along the boom, its angle set by the mainsheet — constantly trimmed for the wind of the moment.
- Headsail (genoa / jib)
- The sail forward of the mast on the forestay — a large overlapping genoa for light winds, a smaller jib for strong. With the mainsail it forms the slot that drives a sloop to windward.
- Battens
- Thin stiffening strips slid into pockets across the mainsail’s trailing edge (the leech). They hold the sail’s curved shape so the leech does not flutter and spill power.
- Telltales
- Short wool or ribbon tufts on the sail that show the airflow. Streaming aft means the sail is set; lifting or stalling means trim — ease until they lift, trim until they fly.
Running rigging
The ropes that hoist and trim the sails.
- Mainsheet
- The block-and-tackle that controls the boom, and so the mainsail’s angle to the wind. Ease it and the sail spills wind; harden it and it powers up — the throttle of a sailing boat.
- Halyards
- The ropes that run up the mast to hoist a sail and hold its head aloft. Each sail has its own — main, genoa — usually led back to the cockpit so sails set without anyone leaving the helm.
- Kicker (boom vang)
- A tackle from the boom down to the mast foot that stops the boom lifting. It holds the mainsail’s shape when the sheet is eased on a reach or run, keeping power in the lower sail.
- Genoa sheets
- The ropes that control the headsail, one each side. The working sheet is winched in to set the sail; the lazy sheet is released across the foredeck each time you tack.
Deck hardware
The fittings that take and hold the loads.
- Winches
- A geared drum that multiplies a crew’s pull, so one person sheets a large sail against tonnes of load. Wrap the rope clockwise, crank the handle, and keep fingers clear of a loaded turn.
- Cleats & clutches
- The fittings a rope is made fast to. A horn cleat takes a figure-of-eight; a jammer or clutch bites the rope at the flick of a lever — between them they hold every line on the boat.
- Fairleads & cars
- Guides that lead a rope to a fair angle without chafe. The genoa cars on their track set the headsail’s sheeting angle; bow fairleads lead the mooring lines ashore.
- Traveller
- A car on an athwartships track that slides the mainsheet’s lower block side to side. It sets the boom’s sideways position independently of sheet tension — fine control of mainsail twist.
Cockpit & steering
Where the crew steer and trim.
- Tiller / wheel
- The lever (or wheel) that turns the rudder. Push a tiller one way and the boat turns the other — simple and direct; larger boats fit a wheel and cables for the leverage.
- Cockpit
- The working well where the crew steer and trim. A good cockpit keeps the crew secure and the controls to hand, and drains itself fast when a wave comes aboard.
- Coachroof (cabin)
- The raised cabin trunk over the saloon, lifting headroom below without losing too much deck. Its windows light the cabin and its top carries handrails, the sprayhood and often the mainsheet track.
Guardrails & safety
The fence that keeps the crew aboard.
- Pulpit
- The stainless guard-rail cage around the bow to lean against while handling the anchor or headsail. Its matching frame at the stern is the pushpit.
- Pushpit (stern rail)
- The guard-rail frame at the stern. It carries the danbuoy, horseshoe lifebuoy and often the liferaft, and gives the helmsman something solid behind them.
- Guardrails & stanchions
- The wires threaded through the deck-edge stanchions, joining pulpit to pushpit — the fence that keeps crew aboard. Clip a harness to the jackstay, though, not the guardrail.
Anchoring next? See the anchor types gallery — and learn to set and weigh in the anchoring lesson.