Steering and Sail Handling - 22nd April
Vega
Hugh and Annie
Sat 22 Apr 2017 21:57
Last night we sailed through with full mainsail and genoa - a first! The wind out here seems fairly predictable, 10-15kts during the day and 7-10kts at night. The moon doesn’t rise until 0300 and before then it is pitch dark so we don’t want anything complicated to do on deck if we can avoid it. However, the mainsail drops very easily and we can put the second reef in from the cockpit without too much bother. Not seeing a squall come up from behind us in the dark is a slight worry but we put the radar on from time to time and that will pick up heavy rain at up to 48 miles away.
As a result of keeping our speed up through the night we have set a new 24 hour record of 148 miles - an average of 6kts. That is the straight line distance taken from the plotter but in practice we will have broken the 150 nautical mile barrier as we don’t sail in a straight line.
One reason we don’t sail in a straight line is the Hydrovane self steering. It is very sensitive to sail trim but the wind varies between 10 and 15kts. At 15kts of wind we get a certain amount of weather helm i.e. the boat points up into the wind. This is due to the mainsail which, as a consequence of the set up of our fractional rig, cannot be let out beyond the point at which the sail hits the backward angled spreaders and shrouds on the mast. In light winds this doesn’t matter much but in stronger wind means that there is a sideways force from the mainsail that pivots the boat around the mast and up into the wind. If you set up the Hydrovane to compensate for this it steers to compensate for the gusts but then oversteers in the opposite direction when the wind is lighter. Just setting it up to steer the course results in the boat oscillating from side to side as it rounds up into the wind in the gusts before the Hydrovane can correct the course.
One way of dealing with weather helm is to reef the mainsail. This moves the centre of effort of the mainsail forward towards the mast and reduces the sideways force with less sail area. With our rig the genoa and mainsail seem well matched for downwind sailing with two reefs in the main. As a compromise we put one reef in the mainsail this morning but found that our overall speed dropped by about half a knot as a result. Now, in the normal way of things a speed reduction of half a knot would be well worth the price of a more balanced boat. However, out here half a knot over four weeks could mean an extra couple of days at sea. Furthermore we are sailing with Nautilus who will naturally sail at between a half and one knot faster than us in the same conditions given her greater length. Our answer to this was the cruising chute. 15kts of wind is around our comfort limit for hoisting and retrieving this sail but we decided to give it a go. It took Annie a while to make sure it would hoist without the various twists and line tangles that are so easy. When it was hoisted the snuffer (the long sock in which the sail is stored and which is pulled up to unfurl the sail within) jammed about two thirds of the way up. Before rushing from the cockpit to assist I noticed that our speed had roared up to 8kts. Flying along at 8kts trying to furl an unruly cruising chute can be daunting - a line wrapped around your leg could have unfortunate consequences. It also takes a lot of pull to get the snuffer back down around the sail in strong winds (although sailing dead downwind to blanket the chute behind the mainsail can help). By the time the sail was retrieved the wind was beginning to rise and within an hour we were up to 7kts with one reef in the mainsail. The next time we try it will be in lighter winds initially………...