Sailing a Catamaran: Reefing, Anchoring with a Bridle and Docking on Two Engines

A cruising catamaran doesn’t tell you when it’s overpowered the way a monohull does, it doesn’t steer like one in a marina, and it needs a bridle to lie quietly at anchor. This guide to sailing a catamaran covers reefing by numbers from the builders’ own manuals, what actually puts cats at risk of capsize, anchoring with a bridle, handling in harbour on two engines, Med-mooring and getting the tender on and off the davits.

Last checked: November 2026. General information only. The reefing figures come from specific owner’s manuals and apply to those boats; your own boat’s manual is the one to follow, and conditions at sea may call for more caution than any table.

Why a cat needs a reefing table

A monohull heels and rounds up when it carries too much sail. A cat stays flat and accelerates. Lagoon’s owner’s manual for the 450S says a catamaran resists heeling about six times more than a monohull, and warns that the lack of heel can hide the fact that you’re carrying too much sail. Both Lagoon and Leopard warn in their manuals that a boat carrying too much sail can capsize; Lagoon adds that it would likely stay inverted.

So you reef on the wind instrument, not on feel. Nikki Henderson, in a 2025 Yachting World piece on multihull skills, makes the point that a cat has no heel to bleed off a gust; the load just keeps building in the rig. Reef early.

What the builders’ tables say

Two examples show how differently builders write their tables. The Lagoon figures come from the current 450S manual; the Leopard ones from Robertson & Caine’s original 2006 manual for the Leopard 46, so a newer Leopard’s manual may differ.

Wind (knots)	Lagoon 450S, apparent wind 30–70°	Lagoon 450S, apparent wind over 70°	Leopard 46 (2006 manual)
Up to 15	Full main, full genoa	Full main, full genoa	Full main, full genoa
15–20	Full main, full genoa	Full main, full genoa (to 20)	1st reef, full genoa
20–25	Full main, full genoa (to 26)	1st reef (20–24), 2nd reef from 24	1st reef, 3 rolls in genoa
25–30	1st reef from 26	2nd reef, genoa 75% (24–30)	2nd reef, 3 rolls in genoa
30–35	1st reef, genoa 75% from 31	3rd reef, genoa 60% (40% from 34)	2nd reef, 6 rolls in genoa
Above 35	2nd reef from 36 (genoa 60%, then 40% from 40), 3rd reef and no genoa 45–55, nothing set above 55	No main from 38, 25% genoa to 50	Storm jib only

A few things stand out. Lagoon’s figures are apparent wind and split by angle: off the wind it wants a reef at 20 knots apparent, upwind not until 26. Leopard gives one set of figures (the 46 manual says they already include a margin for gusts) and starts reefing at 15. Lagoon also tells you to make each change at a wind speed about 10% lower in rough seas, 18 knots instead of 20, for example, and its third-reef line means no main at all if your sail has only two reefs.

The apparent-wind point matters most downwind. Sailing fast off the wind, apparent wind can be far below true wind. Don Margraf, writing in Cruising World (2018, updated 2026), wants reefing checklists written around true wind for exactly that reason, and treats owner’s-manual figures as ballpark numbers: choose cautious ones and keep to them until you know the boat. Henderson adds that builders’ tables seldom allow for sea state.

Our rule: write the numbers on a card at the helm, and reef at the lower of the true and apparent thresholds when you’re heading off the wind. If you’re asking yourself whether to reef, reef.

Getting the main down

A cat’s mainsail is big, fully battened and often slow to come down because the cars bind on the mast. Henderson recommends a topping lift, since many cats have no vang and the boom drops onto the coachroof when the main is lowered, and some kind of downhaul on the luff or roller-bearing cars. Margraf ties a downhaul to the top slide before hoisting so the sail can be hauled down from the mast base. He suggests learning to reef at the dock first, then in around 15 knots on a close reach with plenty of sea room, and only later downwind.

Capsize and pitchpole: the real risk factors

Cruising cat capsizes are rare, but they happen in a few predictable ways. Practical Sailor’s 2021 multihull capsize risk review and the builders’ manuals agree on the main ones:

Too much sail in a gust or squall. Several of the capsizes Practical Sailor reviewed began with a squall or microburst, and it calls sailing on autopilot a common thread. Reef before the squall arrives, not in it.
Turning across the wind. The Leopard 46 manual warns that turning from a run onto a beam reach raises both apparent wind and the heeling force. Turn slowly and reduce sail first.
Burying the bows in following seas. Overtaking a wave at speed can bury the bow, stop the boat abruptly and spike the apparent wind. Practical Sailor points out that heavily flared bows add drag quickly once submerged, and that modern designs have largely dropped that flare.
Breaking seas on the beam. Cats tend to slide sideways rather than roll, but a big breaking wave abeam can still throw one over.

What to do when a gust hits: the Leopard 46 manual says free the sheets; close-hauled, luff up; with the wind on the beam, free the sheets; with the wind aft of the beam, bear away. Keep the mainsheet and traveller ready to run, which means not cleated behind a winch you can’t reach.

For heavy weather, Practical Sailor describes multihull sailors using drogues more than monohull sailors, with a properly sized drogue holding speed to about 4–6 knots to stop the boat surfing. Multihull designer Gregor Tarjan, answering questions for Soundings in 2007, suggests running at a slight angle to the waves rather than dead downwind, because the boat’s diagonal is longer than its length and the bows are less likely to dig in. He keeps a sea anchor for the very last resort on a cat. He also warns that overloading a cat lowers its bridgedeck clearance, which leaves it more exposed in breaking seas.

Anchoring with a bridle

A cat lying to its chain alone sheers around, snatches and grinds the chain on the bow roller or the forward beam. A bridle fixes that. It’s two lines, one from each bow, joined at the chain, so the load sits between the hulls.

On the Lagoon 450S, the manual has the bridle’s legs fixed to the chainplates at the ends of the forward beam rather than to the bow cleats. Henderson’s version for any cat: two identical-length lines from the bow cleats, tied to the chain at the same point with a prusik or rolling hitch. Practical Sailor’s test boat used two 50 ft legs of 11 mm climbing rope, with only about 30 ft of each in use, and suggests 12 mm nylon, three-strand or eight-plait, as the equivalent.

Lower the anchor and pay out chain as you drift back.
When you have the scope you want, attach the bridle to the chain at the windlass.
Pay out more chain until the bridle takes the load and a loop of slack chain hangs below it.
Secure the chain on a stopper or cleat. Lagoon’s manual is clear that the windlass must not be the only thing holding the chain.

To leave, motor up over the anchor rather than winching the boat forward; Lagoon specifically warns against using the windlass to pull the boat. Bring the bridle in before the chain comes up. On the Lagoon 450S the windlass only works with an engine running, which is worth knowing on your own boat before you need it.

Check the strong points too: Lagoon says lines and chain shouldn’t exceed 80% of the anchor point’s breaking strength, and publishes those figures for its boats. If you’re adding a bridle to an older cat, look at where the load goes.

Docking on two engines

Widely spaced engines are a cat’s best feature in a marina. With one ahead and one astern at the same power, a cat turns in its own length without moving forward. Cruising World’s Tony Bessinger (2013) describes the basic rule this way, and both he and the German magazine YACHT advise leaving the rudders centred and steering with the throttles. Gavin Le Sueur, in Yachting Monthly, sees little point in using the helm below about 2 knots on a cat with well-spaced engines.

Prop walk and windage

Many cats have propellers that both turn the same way. Le Sueur’s Multihull Seamanship warns that short, hard bursts then pull the stern noticeably sideways, and in Yachting Monthly he adds that this makes one side the easier one to come alongside. Counter-rotating props largely remove the effect, but then you need bigger rudder movements to move the stern. Find out which you have and which side the boat favours.

Windage is the bigger issue. A cat has high topsides, a tall cabin and shallow keels, so it slides sideways in a crosswind. Practise in open water: stop the boat, see how fast it drifts and which end goes first. If in doubt, Le Sueur suggests a false run past the berth to test windage and current before committing.

Coming alongside

Approach slowly. “Slow is pro,” in Bessinger’s words.
Get a spring on first. Coming alongside to port, a spring from the port quarter, then the port engine slow astern and the starboard engine ahead a little more holds the boat against the dock while the crew sets the other lines.
Use springs from both bow and stern, at least the length of the hull, as Le Sueur recommends; springs from amidships let the ends swing.
Fender the whole hull side; a cat’s straight topsides touch along their length.

Henderson’s advice is to park in reverse with the stern to the wind where possible: better visibility, easier talking to the person on the stern line, and in a tight spot you can do a multi-point turn one engine at a time.

Med-mooring a cat

Stern-to with lazy lines is how most Mediterranean marinas berth you, and a cat does it well. The RYA’s Med-mooring advice adapts directly:

Fenders on both sides and the stern; two stern lines rigged from each quarter, long enough to go ashore and back.
Reverse in. Get the windward stern line on first.
Pick up the lazy line, lead it forward and make it fast at the bow; on a cat, the windward bow cleat keeps the bows from blowing off.
Hold position with small nudges ahead on the leeward engine while the second stern line goes on.
Ease the stern lines, take up the bow line, then haul the stern lines tight so the transoms stay clear of the quay.

On a town quay without lazy lines, drop the anchor about four boat lengths out, as the RYA describes, and reverse in paying out chain. Starting straight and well upwind matters more on a cat because the bows blow off quickly.

The RYA also suggests going bows-to if you’re unsure of the depth near the quay, to keep the drives in deeper water. On a cat, the rudders and saildrives are at the stern; the quay base is the last thing you want to touch them on. Bows-to also needs a passerelle or plank long enough to clear the bow.

The tender and the davits

Most cruising cats carry the tender on davits between the hulls. Lagoon’s 450S manual gives a 200 kg maximum davit load and a 3.5 m maximum tender length, says nobody should be in the tender while it’s being raised or lowered, and tells you to take the outboard off and stow it on board before going to sea. Raise and lower bow and stern alternately so the tender stays level, and avoid it altogether in strong wind or a big swell.

Henderson’s advice is to keep the ends of the boat light: light gear only in the bow lockers, and the outboard stowed off the tender. A lighter tender and a smaller outboard are easier on the davits and on you.

Get some training in sailing a catamaran

Monohull experience transfers, but harbour handling and reefing by numbers are different skills. US Sailing’s Cruising Catamaran Endorsement, taken with or after Bareboat Cruising, has you leave and return to a dock under power, hold station, pivot around the centre and around each hull, manoeuvre on one engine, deploy and recover a bridle and shorten sail. The RYA’s Multihull Seamanship Skills course asks for Level 3 Better Sailing or Stage 4 on a multihull and starts with launching and recovery, which points to beach and sports cats rather than 40-ft cruising boats.

Whichever boat you end up with, start with its own manual; the reefing numbers differ even between builders. The specs database lists sail areas and engine set-ups for the models we cover, including the Leopard 46. If you’re still deciding between types, our sailing vs power catamaran guide may help, and the catamarans for sale are a good way to see which models come up in your price range.

Related guides

Sources

Cover photo: Val Vesa on Unsplash.