It's good that John has remembered what it was like surfacing alongside his upturned Cornish Coble, and has shared his thoughts with us all in his astute comments on 'Last Tack at the Needles' (Bulletin 179).

I'm not sure whether I dare admit that I have spent a large part of my sailing life in... er... er... racing dinghies... and quite a number of my formative years swimming in the water alongside them trying to get a handhold on the immaculately finished bottoms. But the capsizes were always when racing, not 'cruising' – and we did 'cruise' them, all over the Solent.

When sailing to windward a centreboard dinghy is most likely to capsize a) when overpowered by a squall – e.g. jammed mainsheet or b) immediately after a muffed tack or c) and, less likely, when there is a hole in the wind and the crew can't get inboard fast enough and the boat capsizes to windward. It's when in irons or making sternboard or before picking up way on the new tack that an unlucky wave can seal the fate of a boat.

Planning Your Tacks

So plan your tacks, make sure the boat is empty of bilge water, give your crew plenty of advance warning, make sure they are ready, that the boat is making good headway and then choose your moment - either the flattest piece of approaching sea or if it is uniformly rough, tack the INSTANT your chosen wave crest passes your centreboard (tell your crew in advance which wave). Then the boat will be in the wind with no loss of power at the critical moment because the sails are starved of wind in a trough – I'm talking really rough here – and as the boat pivots around its centreboard the wind will push at the bow, especially if you free the main at the instant of tacking and simultaneously the crew holds the jib aback for a moment until the boat is definitely round. Sheet in the jib smoothly but not fully hard before sheeting the main in again. Then harden the jib. If the main is sheeted in before the jib, the boat will instantly round up and you risk getting into irons.

With a cat boat or a lugger without headsails, bear away a little before tacking to get up speed. Boats with mizzens should let the mizzen sheet fly before tacking otherwise this sail will do precisely what it is intended to do and push the bows back into the wind. Then the correct order of sheeting in after the tack is: jib almost home, main in (and then mizzen), then jib hard in.

Sail Trim in Heavy Weather

But a word of caution – many sailors think that just because it is blowing hard they have to sheet their sails in really hard too. This is confusing correct sheeting with correctly flattened sails: that is to say, sails which can be controlled to reduce the camber (flow curvature). On even the most simply-rigged boats it is possible to hoist the jib really tight so a major crease develops along the luff wire. This is significantly more effective than whanging in the sheet on an over-full sail. The creases will disappear when the wind is in the sail. Ditto mainsails: hoist the luff as tight as you can – create a major vertical crease and do the same along the foot. Luggers should harden their peak outhaul until a big crease develops along the yard. Don't worry what it looks like in the dinghy park – the sails will be fine with wind in them – and much more efficient in a blow.

If you have a Cunningham hole on the luff of your sail (a very cheap and effective way of changing sail draught or camber), then use it – hard – when it is blowing. If you flatten your sails this way you can afford not to oversheet which in turn will give more drive and responsiveness. It goes without saying that if you have a boom vang (kicking strap) then you will use this to help control sail shape and twist and this is especially important off the wind. All of these sail tweakings will help you sail better in a blow.

Helm and Rudder

In any boat the helm movement for a rough weather tack should be progressive, not sudden (unless you want to stall the rudder). By 'progressive' I mean start the helm down movement slowly and then faster and faster as the boat turns. In order for your rudder to work there has to be a water flow over the lift side of the blade. The better the aerofoil section of your rudder the less likely you are to stall. An ideal section is the NACA 0010 for maximum coefficient of lift. Flat plywood rudders or even worse, flat metal plate rudders, are particularly inefficient and will stall more readily and sooner than a correctly aerofoiled blade. The lower your boat speed the greater the likelihood of stalling the rudder. Keep the boat moving at all times. In rough weather a transom-hung rudder is also prone to ventilation (air being sucked down the low pressure side of the blade) which will reduce its efficiency dramatically. This is especially true if your boat carries an undue amount of weather helm. Keeping the boat upright helps avoid this.

Off the wind, when the boat is sailing much faster, is when you will need to be very firm and forceful and often sudden with your rudder movements. To stay upright in very rough weather the absolutely golden rule is steer to keep the boat under the mast. In terms of helm movement this can mean being really brutal at times... will your rudder fittings stand the strain? Replace screws with bolts for more peace of mind. And you probably need less sail up than you think. (My Surprise will do almost 4 knots under bare poles and an unreefed ensign at the top end of Force 7.)

Try to ensure your rudder is in the water when you tack. Incidentally, this is why racing dinghies tend to have fairly deep narrow rudders. Deep rudders are altogether better for keeping control. If your rudder is too small or too shallow, you will experience steering difficulties in rough weather and downwind. As a general rule the slower the boat the larger the rudder needs to be. Next time you are in Greenwich go and look at Cutty Sark's rudder. It appears to be minute – but she was a very fast ship.

The Physics of Capsize

If you do muff the tack, then at this point the boat will be blown to leeward and be without any dynamic stability; windage drag on the rig will make her heel and present more and more of the underwater hull to the wind. For an average 15-footer the surface area of half the hull is at least 50 square feet (of windage). How big are your sails? Once this amount of hull is exposed to the wind your masthead will be in the water.

If you can react quickly enough the moment a rough weather tack is muffed you can sometimes save the day. Practise your helm-reversed and jib-backed manoeuvres sometime earlier.

John says that he doesn't think the tide is a factor in causing inversion since the boat would have to be fixed in relation to it. On the basis of an embarrassing amount of practical experience I beg to disagree.

Effectively a boat is 'fixed' if the mast goes in uptide in a wind-against-tide situation as was probable in Richard Gooderick's case in the Needles Channel. The wave action against the hull combined with the windage of the hull is quite sufficient to hold the boat against the opposing force of the tidal stream, so once the mast dips below the surface it is inevitable that inversion will occur as the hull tries to float 'over the mast'. The tide is doing all it can to help achieve this situation by sweeping the mast under the boat. Sufficient masthead buoyancy is the only way to prevent this.

The windage of a hull is considerable – if anyone doubts this, I can assure you that a racing dinghy which has capsized to windward (as frequently happens on a run) and presents its interior to the wind, will have sufficient windage to keep the mast horizontal and for the boat to blow downwind on its side away from its crew significantly faster than they can swim after it. Even with a strong tidal stream pushing a boat towards the wind, a boat which has capsized to leeward (i.e. presenting its underside to the wind) will also blow away from its crew if they lose hold of it, and will only slow its rate of drift when it inverts which, unaided, it almost certainly will. Stay with the boat at all costs.

Buoyancy and Stability

John is absolutely right in pointing to buoyancy disposition as a possible contributory factor in post-capsize stability (or otherwise). Interestingly, the way a boat is decked can also have a marked effect on its capsizing characteristics. A decked 14 ft Merlin Rocket behaves entirely differently to the undecked International 14 in the early stages of a capsize (the comparison here is between boats of 1960's and 70's vintage). Generally speaking the narrower the side decking (the Int. 14 has no side deck) the slower a boat will flip to horizontal since there is a tendency for water to pour in over the gunwale earlier which slows and 'sinks' the boat's reaction. The more buoyant the hull at its beam (ie the wider the sidedecks or the greater the buoyancy apparatus at deck level) the greater the propensity for the mast to go below horizontal before the masthead hits the water. At that moment any buoyancy apparatus located directly under the side decking will indeed speed up inversion unless the crew are very slick with their capsize drill.

A boat which is awash, full of water but kept afloat by its buoyancy, is inherently extremely unstable. It is the mass of moving water in the boat which creates the source of instability as it will move very freely according to the wave action. Since it is rough, this will be considerable. This is why it is vital to have the additional buoyancy and damping effect of the life-jacketed skipper and crew holding on opposite gunwales amidships to reduce the rolling potential.

Whilst writing this it has occurred to me that to have some form of additional buoyancy high up under the side decks or even at gunwale level which could be activated after the boat comes upright might help stabilise the hull.

To fully understand the instability of the water in a hull you could always try a quick but possibly unpopular (though enlightening) experiment, by carrying a shallow baking tray full of water across your kitchen sometime. As you walk give the tray a slight list to starboard and then try to correct the resulting water movement. Now try the same thing with a ton of water in a dinghy...

I repeat – even with the sails down it is possible to re-capsize a boat very easily unless the helmsman and crew are swimming alongside holding each gunwale while they attempt to bale out (a good reason to have one bailing bucket each side on a long lanyard). Do not clamber back into the boat (over the transom for the first person) until the water level is below the top of the centreboard case unless you are cruising (?) in a completely self-draining boat like the Hornet which will shed the water like a surfacing U-boat.

Once back on board don't forget to close your through-hull self-bailers as soon as you get into the boat. Otherwise you'll be doing a lot more bailing than you need to.

Distress Signals

Now let's imagine that you can't get the boat upright and you have an injured or hypothermic crew. (Full marks for John's space blanket recommendation.) This is when you need pyrotechnics. Absolutely no messing. Despite the answer to Question 14 in Len Wingfield's excellent Safety Quiz (Bulletin 185, p.83), and even if you have got a VHF (hands up all those who have got a current licence – it would be interesting to know how popular VHF sets are amongst members), you should have flares on board.

If you are coastal cruising, you owe it to yourself, your crew and your loved ones ashore to invest in a minimum of two each of hand-held red flares and hand-held orange smoke. Orange smoke in daylight if in sight of land or other craft is the best initial action, followed by a hand-held red. Smoke is effective because even after the pyrotechnic burns out, the pall of bright orange smoke blows downwind for some appreciable time and is very distinctive. A potential rescuer will then look upwind to see the source of the distress signal. That's when a flare comes in handy – fire it off about 30 seconds after the smoke has finished. It will absolutely confirm to any observer that there is an emergency.

You should have enough flares and smoke to a) create the initial alarm/alert and b) to be able to provide pinpoint location when a rescue craft approaches. In very rough weather an inverted dinghy hull is a very small target for a would-be rescuer to spot – even for a lifeboat with radar.

In November 1996 Practical Boat Owner carried an article about a single-handed sailor on passage in a 14 ft Aries class dinghy who capsized off Lyme Regis and couldn't reach his flares. Richard Gooderick could not reach his flares on his Wayfarer and we couldn't reach ours on Surprise when we capsized. Ours are stowed in nice neat watertight sandwich boxes shock-corded under the side decks. All these boats were inverted. John Greene has come up with what seems like a brilliant solution. In his comment number 3 (Bulletin 185, p.32) he uses a special flare jar in the cockpit. If this could be arranged to float free of the hull on a lanyard, with lid also lanyarded to the jar this sounds an excellent idea. Securing the jar near the transom or on (but not under) the stern deck (if fitted) should ensure the jar is reachable. You could keep the bulk store of flares in this container.

On Surprise one of our responses to this safety issue for the 2005 season is to have a ribbon strop linking one hand-held red with one orange smoke, and have crew and helmsman each wear this around their necks (but under oilies) in heavy weather. Smoke to Starboard (i.e. hanging on your right hand side) and Red flare to Port makes it easy to remember which is which in an emergency. Then even if we are separated from the boat our survival chances are greatly improved.

We should all realise that the DCA cannot afford to lose subscription paying members.

The writer has built or owned a 12 ft Cherub, Merlin Rocket, 15 ft Ghost, Jollyboat and National 18 and has sailed or crewed (some at championship level) in Laser, Firefly, National 12, Fireball, International 14, Albacore and Flying Dutchman and has capsized in almost all of them. He also completed both of the (two) Lee on Solent to Poole Long Distance Dinghy Races in an International 14.