Cruising Tips – June 2006
This month: MOB maneuvers, radar piloting, and releasing a loaded sheet.
Multi MOB Maneuvers
Catamarans and trimarans do not lend themselves to standard crew-overboard maneuvers. With multihulls there are so many design variables that you need to experiment to find what works best with your boat.
While the mainsail of a monohull can almost always be luffed on a close reach to slow the boat, a typical multihull, with its swept-back spreaders and full-batten mainsail, often must be pointed almost directly into the wind before it slows down. Also, if a multihull is left to drift while its crew is attending to an MOB, the bow will be blown downwind, the main will fill, and the boat will accelerate; this will happen a lot faster than it would on a monohull.
Some multis tack well, while others wont go through the wind in any kind of seaway and need to be gybed instead. In addition, both boat speed and the point of sail can represent significant variables that make it difficult to recommend a standardized procedure. This means multihull owners should design their own MOB-recovery maneuvers. Follow these steps:
- Try stopping the boat by easing the sails. How close to the wind do you need to steer before the boat stops? Note how much (or, equally important, how little) momentum the boat is carrying when the sails are depowered or the engine is put in neutral. Learn how soon the boat will start backing up. Find out how fast it drifts downwind.
- Try tacking and gybing relatively quickly from both a close reach and a broad reach and note any limitations or difficulties you experience.
- Formulate your own crew-overboard maneuvers for use when sailing both upwind and downwind and write out a brief step-by-step description. Decide if the instructions should vary depending on the point of sail.
- Now try the maneuver with a buoy in the water that has some type of weight or drogue so it wont drift quickly to leeward (a fender tied to a bucket works well).
- After testing your method, realistically evaluate what should be changed. Type up a succinct description, and keep copies on board to show to crew and guests.
- Finally, ask other multihull sailors what they would do in an MOB situation. J.C.
The most accurate tool for estimating your distance to a solid target is radar. When you have to traverse a narrow channel close to the shore with off-lying dangers and you cant line up two objects to see you through, select the most appropriate range setting, then set the variable range marker (VRM) to a safe distance from whichever shore seems likely to offer the best radar target. You can then sail or motor along and be sure of your distance off. Double-check everything, make sure you have a bailout plan in case the radar goes on the blink, then forge ahead while keeping the VRM just touching the echo of the shore. T.C.
Letting go the sheet
Releasing a loaded-up sheet from a winch when a boat tacks can be just cause for nervousness. Sailors who have just moved up to big keelboats often underestimate the loads on a sheet. On a boat up to 40 feet or so, the safest way is to first ease off a few inches, keeping the flat of one hand pressed against the turns as they surge round the winch drum. Now take off a turn or two, always leaving a couple on the drum for safety, and wait for the sail to begin to lift at the luff. As soon as this happens, pull the turns positively upward off the drum, keeping your grip directly above the axis of the winch. The turns will whip off cleanly, they will never foul, and your hands will be safe. T.C.
Contributors this month: John Connolly, Tom Cunliffe
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