Jonty Sherwill explains 5 tips for staying afloat when you’ve gone aground.

“The others are in there out of the tide, so let’s tack back in,” you might think in the heat of a close race. But beware; following the others can end up with you going aground. In shoal waters you need concentration and sound navigation; you also need to do your homework to avoid getting caught out by known hazards. Just ask the skippers in Cowes Week or the Round the Island Race!

Even though chartplotters and GPS have made navigation much more straightforward, it’s still easy to push a bit too hard to cheat the tide or simply miscalculate the depth. If you are sailing over mud, the consequences of grounding are likely to be embarrassing rather than serious, but getting stuck on rocks or hard sand requires decisive action.

The urgency of your response will be influenced by tidal conditions – a falling tide at the top of springs can mean a long stranding and, when combined with waves, the risk of structural damage is very real.

As often as not a quick tack will see you off and back in the race, but if there has been a significant impact with a rock or prolonged pounding on a hard bottom, it’s advisable to have the keel and structural floors inspected as cracks in this high-stress area can develop unseen over time.

1. Stay afloat! Running aground is almost always a race-losing move, so avoidance is the best policy. In the Solent we push in to less than half a metre below the keel when it is a flat, soft bottom such as the mainland shore west of Beaulieu, but we would never do that on the Island coast opposite. Here a permanent watch on the chartplotter is required, with continual checks against the echo sounder.

All the crew should be briefed on the immediate action. For instance, the navigator might say: “I expect it to go down to 0.3 of a metre for the next 200m, deep water is to starboard if we touch.” On a falling tide we work to a slightly safer margin.

If you touch, “tack” is a common instruction to the helmsman. The momentum of the boat can drive the keel through the mud, so keeping the jib backed after the tack will help to increase heel, thus reducing draught until the boat is back in deeper water.

2. It’s vital to know if the tide is rising or falling, and if the tide flow and/or wind is pushing you on, or helping you off. Hoisting a spinnaker could be the answer, but if the tide is at maximum ebb you lose depth very rapidly, so turning the engine on or getting a tow off may quickly become your only options.

This will mean retirement from the race (unless RRS 42.3(i) is stated in the SIs), but this is preferable to the boat lying down on its side and a long wait for the new tide. If that happens (and it is safe to do so) the cabin floorboards can be used to cushion the hull on a stony shore to prevent more serious damage. It’s unlikely the floorboards will survive the experience, but it would be a small price to pay for an undamaged hull.

If you go hard aground at high water on a spring tide then forget the race and call for help immediately.

3. Which way off? The way you ran into trouble may be also be the best way out, particularly among rocks. Keep cool and keep a grip of the navigation and the boat’s heading. In clearer water have someone positioned on the bow to shout directions to the helmsman, but if the water is muddy, the spinnaker pole can be used to test the depth. However, the crew must hang on tight as another big bump could happen at any moment.

4. Have an action plan. It will save time if the crew know what to do if you run hard aground, as instant action is needed. Do everything possible to increase heel and reduce draught; you may need weight forward as well as to leeward. One or more crewmembers sitting on the main boom as it is let out will help increase the heel, but should really only be attempted using a bosun’s chair for additional safely and after the mainsail has been lowered. If someone is nearby who could help with a tow, call them up just in case you are going to need outside assistance.

In shallower-draught dayboats hopping over the side to push off may be the answer – this also helps by reducing the displacement of the boat. It can be risky in anything but light airs and a buoyancy aid should always be worn – plus having a foot loop rigged will help you get back on the boat.

A push off like this with no outside help also avoids retirement from the race.

5. Taking a tow. If all else fails and there is serious risk to the boat or crew, you should call for help early. While an RNLI lifeboat crew will be briefed for the particular situation you are in, if the tow is offered from a passing motorboat or RIB it helps to know what will work best and to avoid unnecessary damage.

Depending on how hard aground the boat is, a line attached to a spinnaker halyard could work best. These are designed for an angular pull. If the boat is fractionally rigged, never use a main halyard as the strain will not be taken by the shrouds and increases the risk of breaking the mast.

This is an extract from a feature in Yachting World August 2014 issue