Heavy Weather Sailing Tactics - Reefing & Heaving To

Prerequisites

You should have:

• Day Skipper level boat handling, including reefing and sailing to windward in a Force 5.
• Completed the Advanced Meteorology lesson: fronts, barometer tendency and forecast comparison.
• Completed the Coastal Passage Planning lesson: tidal gateways, wind against tide and contingency harbours.
• Ideally, sea time in Force 6 or more with an experienced skipper. The Yachtmaster Coastal exam does not require you to have sailed in a gale, but the examiner will expect you to know how to prepare a yacht and crew for one, and to reef and handle the boat confidently in the conditions on the day.

Learning Objectives

By the end of this lesson you will be able to:

• Prepare a yacht and crew for heavy weather before it arrives (RYA Coastal Skipper syllabus: heavy weather preparation).
• Interpret gale warnings and pressure-change terms and make a go or no-go decision.
• Manage sea room and lee shores, enter harbour or anchor in heavy weather, and deal with damage and towing (syllabus: coastal storm tactics, emergency management).
• Decide when to reef and carry out slab reefing efficiently.
• Choose and rig storm sails.
• Assess sea state, including wave period, steepness, shoaling and wind against tide.
• Explain and choose between heaving to, running off, sea anchors, drogues and lying ahull.
• Recover from a knockdown and know how to reduce the risk of one.
• Keep crew safe on deck and below in heavy weather.

Syllabus Map

This lesson covers the heavy weather sections of the RYA Coastal Skipper / Yachtmaster Coastal practical syllabus (and prepares you for the Yachtmaster Offshore exam).

On the Coastal Skipper course the instructor will ask you to plan and carry out a passage in Force 5 to 7 if conditions allow, and to describe what you would do in Force 8 or above. Know your numbers: reef points, heel angles, the tide at the headland.

The Best Heavy Weather Tactic: Avoid It

Most yachts that get into trouble do so near land: rounding headlands, crossing bars or approaching harbours in onshore gales. The most important heavy-weather skill is the decision not to be there. For a coastal skipper that means reading forecasts and the barometer critically, leaving harbour only when the boat and crew can handle the worst plausible case, and diverting early. If caught out, sea room is safety: a well-found yacht is usually safer well offshore than trying to enter a harbour with breaking seas across the entrance.

Preparation

Prepare while it is still easy. Once the boat is heeling and pounding, every task takes three times as long and seasick crew lose interest in everything.

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Boat

• Stow and lash everything below: floorboards secured, heavy items (batteries, anchors, tins) restrained, locker lids fastened. A loose tin becomes a missile in a knockdown.
• On deck: lash the dinghy, remove or lash the sprayhood if necessary, secure the anchor so it cannot work loose, check lifelines and jackstays.
• Close all hatches and seacocks not in use; fit washboards, and secure them so they cannot fall out in a knockdown.
• Clear cockpit drains.
• Prepare storm sails, reefing lines, and the trysail track if fitted.
• Pump the bilges dry so you can see any new water.
• Charge batteries; check fuel and fuel filters (rough seas stir up sediment and engines often stop at the worst time).

Navigation

• Fix your position and plot it on the paper chart.
• Reassess the plan: sea room to leeward, tidal streams over the next hours, ports that can be safely entered in this wind.
• Prepare a hot meal and flasks now; make sandwiches.

Crew

• Brief the crew: what to expect, the plan, watch rota, harness rules, MOB procedure.
• Issue seasickness remedies early (they need time to work).
• Everyone in full foul weather gear and lifejackets with harnesses before conditions deteriorate.

Reefing

When to reef

The old rule "if you think about reefing, you should have done it already" still holds. Reef for the gusts, not the mean wind, and reef before dark or before a front.

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A typical 10 to 12 m cruising yacht might reef as follows (adapt for your boat; lighter, tender boats reef earlier):

Signs you are over-canvassed: excessive heel (above 25 to 30 degrees), heavy weather helm, rounding up in gusts, the rail in the water. A reefed boat is faster, drier and much more controllable.

Slab reefing

1. Brief the crew and choose your moment (on starboard tack if you want right of way during the operation).
2. Ease the mainsheet and kicker to depower the main; take the weight of the boom on the topping lift or rigid vang.
3. Ease the halyard to the marked reef point.
4. Hook on or pull down the tack reef cringle and secure it.
5. Re-tension the halyard until the luff is tight.
6. Haul in the clew reefing pennant until the clew is down on the boom and the foot is tight.
7. Retrim the mainsheet and kicker; ease the topping lift.
8. Tie in the reef points loosely around the loose sail (around the sail, not the boom) if needed.

On a boat with single-line reefing, steps 4 and 6 are combined. Practise in moderate conditions until your crew can complete a reef in a few minutes.

Storm sails

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A storm jib should be set on an inner forestay or a dedicated stay, not over a furled genoa: a furled sail can unroll in a gale and is extremely hard to recover. A trysail hoisted on its own track replaces the mainsail, takes no load on the boom and can be sheeted to the quarters. Bend on and practise hoisting storm sails in calm weather. Hoist them before the peak of the blow.

In-mast furling mains can jam; point head to wind to reduce load, never force the mechanism, and if a jam occurs partially unroll to clear it. Secure furling lines so they cannot be released accidentally.

Forecasts, Warnings and the Go or No-Go Decision

Heavy weather is usually forecast. The skill is in reading the forecast critically and having a plan.

Gale Warnings and Forecast Terms

A forecast of "Force 7 to gale 8 later" means the worst may be 6 to 12 hours away. Check the next shipping forecast, inshore waters forecast, Navtex and the latest synoptic chart, and compare them with what you see. Log the barometer every hour in a developing situation.

Beaufort Wind and Sea State

Heights are for a fully developed sea. With limited fetch, such as close under a coast, waves are smaller but steeper, while a tide against the wind can double their effect.

The Go or No-Go Decision

Before leaving harbour, ask these questions and write down the answers in the passage plan:

1. What is the worst forecast for the whole passage plus 12 hours? Can the yacht and crew handle that, and is there a safe harbour to run to?
2. Are the tides, bar depths and entrance conditions of the destination and of every bolthole suitable in that wind direction?
3. What is the weakest crew member's condition, and how many are experienced enough to steer in rough weather?
4. What is the escape plan if the wind arrives early, or the front arrives faster than forecast?

If the answers are uncertain, stay in port. The RYA examiner values a skipper who stays in harbour for the right reasons far above one who sails and has to be rescued.

Sea Room and Lee Shores

A lee shore is a coast onto which the wind is blowing. In a gale a yacht under sail or at anchor can be driven onto one, because a yacht cannot always claw to windward in steep seas. The danger is greatest where there are no harbours that can be entered in the conditions.

• Keep at least 10 miles to leeward of dangers whenever possible when a gale is forecast. At a drift of 1.5 knots, a heaved-to yacht moves 18 miles in 12 hours.
• Allow for leeway (typically 5 to 10 degrees in heavy weather) and for tidal stream in the course you steer.
• Plan to claw off a lee shore with the engine and storm sails together: keep the wind 50 to 60 degrees off the bow, make as much speed as possible and constantly check for tidal set.
• Do not rely on the engine alone. Rough seas stir up sediment in the fuel tank, and the propeller can come out of the water in pitching. Check fuel filters before the weather arrives.
• Anchoring in the lee of a headland is a last resort, not a plan. The holding must be good and the anchor and chain must be sufficient for the conditions.

Sail Balance, Helm and Heel

A well-reefed yacht sails upright and in balance, with slight weather helm of 3 to 5 degrees of rudder. If the helm is heavy, the boat is overpowered. Cures:

1. Flatten the main (more outhaul, cunningham, vang, backstay if fitted) and traveller down.
2. Heavy weather helm usually means the mainsail is too big, so reef the main. If the helm is light or the boat carries lee helm, the headsail is too big, so reduce that first. Aim to keep the sail plan balanced fore and aft.
3. Move crew weight to windward and aft. Keep bunk contents low.
4. Check for the angle of heel: above 25 to 30 degrees, a cruising yacht loses speed and efficiency, and the keel and rudder lose grip.

A well-balanced reefed boat can steer with the autopilot in a surprising amount of wind, but the autopilot can be overwhelmed by a big wave or gust, so be prepared to take over. Keep the helm sheets and halyards clear, and ensure nobody is standing in the loop of a sheet or on a jammed line in a gust.

Headsail and Mainsail Reefing Order

Always practise the sail plan in moderate wind first, and set sail marks (coloured tape) on the halyards and reefing lines so that the crew can find the reef positions at night.

Understanding Waves

Steepness and period

Wave height alone does not tell you how dangerous the sea is. Steepness (height divided by wavelength) and whether waves are breaking matter more.

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A long, regular Atlantic swell of 4 m with a 14-second period is comfortable; a 3 m wind sea with a 6-second period in a tidal race can roll a yacht over. Waves break when steepness reaches roughly 1 in 7. A breaking wave whose height is equal to or greater than the yacht's beam can capsize it if it strikes beam-on.

What makes waves steeper

• Wind against tide: a strong stream running into the wind shortens and steepens the waves dramatically.
• Shoaling water: as depth reduces, waves slow, shorten and steepen; they break in water roughly 1.3 times their height. Banks, bars and the edge of the continental shelf are dangerous in gales.
• Headlands and races: stream, overfalls and wind acceleration combine.
• Fetch and duration: the longer the wind blows over open water, the bigger the sea. A change in wind direction creates a cross sea that is confused and dangerous.

Storm Tactics

There is no single correct tactic; choose based on the boat, the crew, sea room and the sea state.

Heaving to

Heaving to stops the boat in a stable, controlled attitude, useful for reefing, cooking, resting, navigating or waiting for daylight or tide.

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1. Sail close-hauled under reduced sail.
2. Tack without releasing the jib sheet, so the headsail is backed.
3. Ease the mainsheet partly.
4. Lash the helm to leeward (tiller to leeward, or wheel turned to windward) so the rudder tries to turn the boat into the wind.
5. The backed jib pushes the bow away; the rudder and main bring it up. The boat settles 45 to 60 degrees off the wind, drifting slowly to leeward at 1 to 2 knots.

The turbulent "slick" to windward helps to calm breaking crests. Heaving to on starboard tack gives you right of way over other sailing vessels. Modern fin-keeled yachts may fore-reach or refuse to settle; find the right combination of sail and helm in moderate weather first. It needs sea room to leeward.

Running off

When there is sea room downwind, running off with the waves on the quarter or stern under reduced sail (storm jib or bare poles) reduces the apparent wind and impact of the waves.

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Dangers: surfing too fast, burying the bow (pitchpoling in extreme seas), and broaching, where the boat slews beam-on and is knocked down. Keep enough speed for steerage, steer to take each wave slightly on the quarter, and slow the boat with warps or a drogue towed astern if speeds exceed what the helmsman can control. Running off is demanding on the helmsman; rotate frequently.

Sea anchors and drogues

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Both need strong attachment points, chafe protection and a plan for retrieval (a trip line on the sea anchor; a winch for the drogue). They are mostly offshore tools, but coastal skippers should understand them.

Lying ahull

Lying ahull means dropping all sail, lashing the helm and letting the boat lie as it will, usually beam-on to the sea.

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In moderate conditions it can allow a tired crew to rest, but in breaking seas it exposes the boat's full length to breaking crests and greatly increases the risk of knockdown or capsize. Treat it as a last resort; heaving to, running off with a drogue or a sea anchor are better.

Knockdowns

A knockdown occurs when a breaking wave or gust lays the boat over with the mast near or in the water. Most yachts come back up quickly thanks to the ballast keel.

Immediate actions:

1. Release sheets to spill wind and reduce load.
2. Account for every crew member, on deck and below. Look for anyone in the water.
3. Let the keel bring the boat upright.
4. Check for injuries, water ingress, damaged rig (shrouds, mast step, spreaders) and lines in the water near the propeller before using the engine.
5. Pump the bilge, clear up, reassess the tactic.

A 360-degree roll (capsize) is rarer but can dismast the boat. Prevention: avoid breaking seas, stay off shoals and races, avoid lying ahull, reef early, keep washboards and hatches secured, and stow everything.

Crew Safety

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• Harness and tether: clip on before leaving the companionway and stay clipped on. Use a tether with two clips (short and long) so you are never unattached. Clip to strong points or jackstays, never to guardwires.
• Jackstays: webbing jackstays run fore and aft along each side deck, so crew can move to the bow without unclipping. Webbing does not roll underfoot as wire does.
• Minimise numbers on deck: keep off-watch crew below and warm; hypothermia and seasickness sap decision-making.
• Cockpit: a large cockpit filled by green water weighs tonnes; keep drains clear and washboards in.
• Fatigue: rotate helmsmen every 30 to 60 minutes; ensure people eat and drink.
• Seasickness: a seasick crew member on deck must be clipped on; vomiting to leeward over the guardwires is a common MOB cause.

Entering Harbour in Heavy Weather

Many accidents happen at the harbour entrance. When the wind is onshore and the tide is against it, a breaking bar can be impossible to cross.

1. Check the pilot book, the chart and the harbour authority for the state of entrance at that stage of tide. Many entrances are safe only near high water or when the stream is in the same direction as the swell.
2. Call the harbour master or coastguard by VHF for entrance conditions and advice.
3. Prepare the yacht: lifejackets and tethers on, fenders and warps rigged on the correct side, anchor ready, engine running and checked, and the sail plan reduced. Lower or furl sails inside the harbour pier heads, not before, so there is power to hold position.
4. Enter in line with the leading marks, with the swell coming from astern or on the quarter. Keep the speed up enough to steer, because the yacht can slew sideways and broach when the waves overtake her.
5. If conditions are too rough, do not try. Turn back, heave-to or run to sea room. An abort made in time is not a failure.

Heavy Weather Anchoring

A yacht anchored in a rising wind may drag. If the anchor must be used:

• Veer scope to at least 5:1 (chain) or 7:1 (rope), and more if the depth is increasing as the tide rises. In a gale, 7:1 or more is usual.
• Use a nylon snubber or bridle to absorb shock and prevent chain snatch.
• Set an anchor alarm on the GPS and keep an anchor watch. Take transit bearings to check for dragging.
• Run the engine and be ready to motor up to the anchor in a gust. Know how and when to leave the anchorage.
• Consider a second anchor in a V (about 45 degrees apart) if the wind is likely to veer. This needs space to swing.

Damage Control and Towing

• Steering failure: fit the emergency tiller, hand-steer, or steer with sails and a drogue.
• Rig damage: ease the sheets, head up or down to take the load off, support the mast with halyards and tackles, and clear the wreckage if the mast falls.
• Flooding: follow the lesson on fire, flooding and abandon ship; collision mat, bungs, putty, pumps.
• Towing: as the tug, use a long tow with a bridle, a snatch protector, and a slow start. As the towed yacht, prepare a bridle from two strong points (such as the mooring cleats led through fairleads) and check chafe. Agree terms (towage not salvage) before you accept any tow.
• Helicopter rescue: clear the deck of loose items, lower the sails, hold the course and speed the helicopter crew request (usually with the wind on or just forward of the bow), and follow their instructions. Do not attach the winch wire to the boat before earthing it (let the wire touch the water first).
• Lifeboat: the RNLI coxswain will say how to approach. Keep fenders ready.

Watertight Integrity

In a knockdown the sea can enter through the companionway, hatches, vents and cockpit lockers. The aim is that no single failure can flood the boat. Check:

• Companionway washboards fitted in sequence, with lanyards, and strong enough to resist a breaking wave.
• Hatches dogged down, and no leaking opening ports.
• Cockpit lockers latched with proper clips, because a locker lid blown open can flood the hull via the stern.
• Cockpit drains clear, of adequate size, and fitted with non-return valves where necessary.
• Seacocks closed on the lee side in heavy heel, particularly for the heads and sink.

Worked Example: Caught by a Front

You are on passage along the south coast in a 34 ft yacht with four crew. The forecast was SW 5 to 6. At 1600 the barometer has fallen 5 hPa in three hours and the wind is gusting 30 knots. You are 12 nm from your destination, whose entrance has a bar that breaks in strong onshore winds; 20 nm downwind is a large all-weather harbour.

1. Recognise. A 5 hPa fall in three hours is "quickly": expect Force 7 to 8, and a cold front later with a sharp veer to the west or north-west.
2. Prepare. You put in the third reef and roll the genoa to a scrap, then rig the inner forestay and hank on the storm jib ready. Hatches and washboards secured. Crew briefed, harnesses on, hot drinks in flasks.
3. Decide. The destination bar will be breaking; abort it. You bear away for the all-weather harbour, running with the wind on the quarter. Tide over the next four hours is fair and the route has no headland races.
4. Execute. The wind reaches 38 kn in squalls as the front passes at 1900. You hand the main and continue under storm jib, steering to take seas on the quarter. Speed is 7 kn, within control; no drogue needed.
5. Arrive. Pilotage plan prepared before arrival, approach in the lee of the breakwater. Log written up: decision times, barometer readings and reasons.

Worked Example: Wind Against Tide at a Headland

You plan to round a headland with a tidal race on the way to a destination 30 miles away, in a forecast of SW Force 6 gusting 7. The tidal atlas shows a south-going stream of up to 3 knots running into the south-west wind for three hours around mid-tide.

1. In light winds the race would be a lively patch. With 27 to 33 knots from the SW and the stream running into it at 3 knots, the waves are much shorter and steeper. A 3 m sea at 8 seconds period would become closer to 4 m at 5 seconds. Steepness would rise from about 1 in 20 to about 1 in 10, and waves are close to breaking at 1 in 7.
2. The tidal atlas shows the stream slackens and turns, one hour either side of the turn, at HW Dover plus 2. The options are: wait in harbour and pass at slack water, pass outside the race by about 5 miles, or choose another route.
3. You calculate that at 6 knots you could reach the race at HW Dover plus 2 and pass just as the stream turns, with the new stream running in the same direction as the wind and flattening the sea. You write the times in the plan with a reserve of one hour.
4. You decide to leave harbour 90 minutes later than planned. You reduce to the second reef and storm jib or working jib before the race, and check every crew member is clipped on before you enter.

The lesson: the timing of the tide often decides whether a headland is a Force 6 problem or a Force 8 one. Always consult the tidal atlas as part of the heavy weather decision.

Worked Example: Heaving To with a Lee Shore

You are 25 miles from a lee shore in a Force 8 gale, with a tired crew. The yacht heaves to well on starboard tack, drifting at 1.5 knots.

1. Calculate: at 1.5 knots the yacht drifts 18 miles in 12 hours, leaving a margin of 7 miles. The gale is forecast to last 14 hours. The margin is therefore not enough.
2. Add tidal drift. If the stream runs towards the shore at 1 knot on average over 12 hours, add 6 nm to the drift. The margin is now 1 mile.
3. Decision: do not rely on heaving-to alone. Set the storm jib and trysail (or deep-reefed main), claw off at 40 to 50 degrees off the wind while there is daylight, and use the engine to maintain steerage. If the yacht cannot make progress, then deploy the drogue or sea anchor as a last resort to slow the drift.
4. Calling the coastguard early with a PAN PAN allows them to plan for a possible rescue.

Lessons from the Heavy Weather Literature

Rolling and wave dynamics: why boat size and wave size matter

Breaking waves most dangerous to a yacht are those with a height approaching a third to a half of the boat's waterline length, particularly in short, steep seas over shoaling water, tidal races and wind against tide. A 10 m yacht is at risk from a breaking crest of 3 to 4 m, while a 15 m yacht needs a crest nearer 5 to 6 m. In deep water a wave travels at roughly 3 knots for every second of its period, so a 10-second swell moves at about 30 knots and a 12-second swell at about 36 knots. A yacht running at 8 knots cannot outrun a wave; she is overtaken by it.

Wave height and wind: what to expect

As a rule of thumb, a steady Force 8 (about 37 knots) with sufficient fetch and duration gives a significant wave height of about 5.5 m, with the highest individual waves nearly twice that. Fetch and duration limit the size: in a short fetch, such as the Solent or the Bristol Channel in a westerly, a lower height but steeper and shorter sea develops. Add tide against wind and the seas steepen markedly. As a rule of thumb, a stream running against the wind at 3 knots in Force 6 can double the wave height.

Storm tactics: the Coles approach to deciding

Adlard Coles' classic study of storm tactics, from his own experience and from many other skippers, reaches the same conclusion repeatedly: no single tactic is best for every boat and every storm. The decision depends on sea room, the boat's design, crew strength and the type of sea. The tactic must be chosen early while the crew is fresh. In general:

• Under sail, close-hauled or hove to is best while the boat can make some progress to windward with a trysail and storm jib, or when she heaves to well. Many modern fin-keelers heave to comfortably with a deep-reefed main and backed storm jib; some will not, and you must know before the storm arrives.
• Running off under bare poles or storm jib with warps or drogue is the choice when sea room allows and the boat can be steered. The danger is broaching and pitchpoling, and the loss of control as speed rises. A drogue can reduce speed to 3 to 4 knots and keep the stern square to the sea.
• Lying to a sea anchor is a last resort for most cruising yachts, and is best deployed from the bow only on boats known to lie head to wind.
• Lying ahull is only a short-term solution in moderate seas and has repeatedly led to knockdowns in steep seas.

Drogue and warp specifications

A series drogue of 100 to 150 small cones on a long line, designed by Don Jordan, is widely regarded as the most effective stern device for a yacht. It reduces speed to 1 to 2 knots and keeps the stern to the waves. Anchor the line to strong points on both quarters through a bridle; each cone adds a few kilograms of drag; the total load can reach several tonnes in a storm, so the attachment points need backing plates. A conventional drogue (a single large cone) is faster to deploy but gives less control. Warps trailed in a bight are a classic alternative: use 100 to 150 m of 20 mm rope in a loop, with tyres or chain, and adjust the length until the stern holds square.

Worked example: choosing storm tactics

A 12 m cruiser is 45 M offshore in the Western Approaches, with a southwest Force 9 forecast building to Force 10 within 6 hours. Sea room downwind is over 200 M. The barometer has fallen 14 mb in 6 hours. Crew of four; one is seasick.

1. The wind is forecast to veer rapidly to the northwest as the front passes, which will bring a cross sea.
2. The skipper decides to reduce to the storm trysail and storm jib while the crew can still work on deck, rig the jackstays and ready the series drogue.
3. Heading southwest would be close-hauled to a rising sea. Heave to on starboard tack, sailing slowly west of north, lets the boat drift gently to leeward with the slick. The log notes drift of 1.5 knots.
4. If the veer produces a confused sea, switch to the drogue running east-northeast, with the helm lashed and the hatches secured.
5. Every hour the barometer and sea state are logged, and the plan reviewed.

Care of the crew and boat after the storm

After the storm, inspect the rig, the rudder, steering, hull and hatches. Check the engine and batteries. Pump bilges, sort out any wet lockers, and have everyone eat and sleep before resuming the passage. Make a safe landfall rather than pressing on; accidents happen disproportionately in the exhaustion after heavy weather.

Common Mistakes

• Reefing too late. Reefing in 35 knots is dangerous and slow; reef at the first sign.
• Preparing too late. Do the checklist before the weather arrives.
• Heading for a dangerous harbour entrance. Sea room is often safer than shelter behind a breaking bar.
• Storm jib over a furled genoa that then unrolls.
• Lying ahull in breaking seas.
• Unclipping on deck, even briefly, or clipping to guardwires.
• Ignoring the barometer because the forecast was benign.
• Exhausting the skipper. A tired skipper makes poor decisions; delegate and rest.

Summary

• The best heavy-weather tactic is to avoid it through planning and early diversion; sea room is safety.
• Prepare boat, navigation and crew before conditions deteriorate.
• Reef early, for the gusts; practise slab reefing and storm-sail hoists in calm weather.
• Wave steepness, breaking and wind against tide matter more than height; avoid shoals and races.
• Heave to for a controlled stop, run off when sea room allows, use drogues to control speed and sea anchors when sea room is limited; lying ahull is a last resort.
• After a knockdown: release sheets, count crew, check rig and hull before starting the engine.
• Harnesses on and clipped to jackstays; minimise exposure; manage fatigue and seasickness.

Check Your Understanding

1. List five things to prepare on board before heavy weather arrives.

Answer: For example: stow and secure everything below, lash deck gear, close hatches and fit washboards, rig jackstays, clear cockpit drains, prepare storm sails and reefing lines, pump bilges, fix position, prepare food, brief crew and put on harnesses.

1. Why should you reef for the gusts rather than the mean wind?

Answer: Gusts can be 30 to 50% stronger than the mean wind and arrive suddenly; a boat reefed only for the mean will be overpowered, hard to steer and at risk of rounding up or damage in each gust.

1. Describe how to heave to.

Answer: From close-hauled, tack without releasing the jib so it is backed, ease the main, and lash the helm to leeward so the rudder steers into the wind. The boat lies around 45 to 60 degrees off the wind, drifting slowly to leeward.

1. Why is wave period as important as wave height?

Answer: Short-period waves of the same height are steeper and more likely to break. A breaking wave as high as the boat's beam can capsize it, while long-period swell of greater height is relatively safe.

1. When would you use a drogue, and when a sea anchor?

Answer: A drogue from the stern controls speed when running off, preventing surfing and broaching. A sea anchor from the bow holds the boat almost stationary, bow to sea, when sea room is limited or awaiting rescue.

1. Why is lying ahull dangerous in breaking seas?

Answer: The boat lies beam-on with no control, exposing its full length to breaking crests, which greatly increases the risk of knockdown or capsize.

1. What should you check before starting the engine after a knockdown?

Answer: That no lines, sheets or rigging are in the water near the propeller, as well as the condition of the rig, hull, crew and the engine itself.

1. Why should a storm jib be set on an inner forestay rather than over a furled genoa?

Answer: A furled genoa can unroll in gale-force winds and is then extremely difficult to recover; the inner stay also brings the sail's centre of effort inboard and aft, improving balance.

1. Your destination has a bar that breaks in onshore gales. A gale is approaching. What should you consider?

Answer: Do not attempt to cross a breaking bar. Divert to an all-weather harbour, or stay at sea with ample sea room until conditions improve.

1. A forecast says "Severe gale 9 soon" and the barometer has fallen 7 hPa in the last three hours. How soon should you expect the wind, and how would you describe the barometer change?

Answer: "Soon" means within 6 to 12 hours of the time of issue. A fall of more than 6 hPa in 3 hours is "falling very rapidly" and indicates a deep or fast-moving depression. Prepare the yacht immediately and expect the wind earlier than forecast.

1. At 3 knots of tide against a Force 6 wind, what happens to the waves, and how would you plan around it?

Answer: Wind against tide makes the waves shorter and steeper, which can double the effective danger, and may cause breaking waves at a headland race. Plan to pass at slack water or when the stream turns to run with the wind, or stay well outside the race.

1. Describe the safe procedure for entering a harbour with a bar in heavy weather.

Answer: Check the pilot book and harbour authority for conditions at that state of tide, call by VHF, prepare crew, fenders, warps and anchor, enter in line with the leading marks with the engine running and enough speed to steer, and abort and stay at sea if the bar is breaking.