- Elaine Bunting
- Comments (1)
ARC rally: broken booms
Broken booms are a annual part of the gear casualty list of the transatlantic ARC rally. When you consider the strain, continual motion and loads exerted on them during two weeks or more of robust downwind sailing, it's not surprising.
More often than not, however, boom breakages are the result of an accidental gybe or of a badly led preventer, one taken, say, from mid-boom or to midships. Even when the boom is correctly prevented by a line from the boom end to the bow and back to the cockpit (ideally using a braid on braid line so there's a bit of give in it and led to a winch so it can be released quickly if the boom end dips in the water), the strain of a boom slamming or of battens gybing violently can cause damage.
Accidental gybes are really difficult to avoid when sailing downwind on an ocean passage. The seas are usually bigger than inshore - they were on the ARC this year - and can be overlaid with a cross sea so that they are disorganised and random. There's a lot of concentrated wear and tear.
Add to that mix a tired helmsan steering in the night, perhaps with the moon not due to rise for hours and the surroundings pitch black and it's easy to understand how easy to stray off course.
There are also squalls, which usually arrive with a sizeable windshift; maybe 20° or more.
So I'd go so far as to say that the majority of boats on a downwind ocean crossing such as the ARC rally experience one or more accidental gybes.
But not all boom breakages are as a result of a gybe. The photo above shows the boom of Ian and Annie Darby's X-55 Jus' Do It V. It cracked with a bang while Annie was on watch on night and sailing along in 22 knots of wind, nothing untoward happening.
She says she went on deck with a torch and saw a crack just above the tang fitting where the kicker attaches. On closer inspection later another crack was forming at the forward end of the tang.
The crew got the mainsail down, but the boom cracked completely and scissored across the coachroof, as you can see here.
Another boom breakage that seemed to have no single cause was on Triumph, Swedish sailor Börje Toresson's Baltic 64. Whitbread and Volvo Ocean Race skipper Magnus Olsson was sailing on board and reported that the boom had given way for no particular reason. Maybe fatigue? The yacht is 17 years old.
They continued flying the mainsail loose-footed, sheeting the clew to winch via a block on the quarter.
As well as booms several goosenecks and vangs broke, also mainly as a result of accidental gybes. There's no magic answer to this since accidental gybes can be so hard to prevent in practice, but if planning an ocean crossing, double check for cracks and if necessary beef up all the standard fittings.
Photo courtesy of Clare Pengelly