Monday, July 23, 2007

Life at Sea...Driving

Of the topics we have discussed one that was missed was driving. What is it like to drive a 12,000 lb 37 foot surf board downwind? First we should outline some technical details. Two forces move boats wind and engines of course we use wind, as well there are two methods of directing that force a steering wheel or a tiller, each of which move a rudder. The easiest most common sense system is to use a wheel. That’s because for the most part we all drive a car (even a toy car) and its works the same as a boat - turn left go left. The second method is the tiller a more traditional method which for some seems counterintuitive to use, to go left you push right. If your trying to get your mind around that concept it is actually exactly like a steering wheel. Just drive to work tomorrow with one hand on the bottom (6 o’clock position) of the wheel you will find that the right hand turn you need to make will require you move that low hand left….simple. A true significant difference in between the two systems is that with a wheel there is often times some form of mechanical advantage built into the system either with cables, chain, hydraulics, pneumatics etc. This can often time leave the driver potentially disassociated with the rudder action which can be overcome with time and practice. On the other hand the tiller is attached directly to the rudder. What the rudder feels the helmsman feels, a very direct and immediate action and reaction feeling and response.

Learning to drive a racing sailboat is on to itself a skill as honed and necessary as all of the other positions on board. From the outside it seems to appear that the helmsman is not working as hard as the bowman or mast man or the trimmers and grinders, but the subtle actions taken by the helmsman are directly related to the efforts of the trimming crew and tactician, it is they that ensures the crews efforts reap the most out of speed and distance. So imagine you are in a larger following sea; looking outside right now it is a consistent 6 – 8 feet of ocean swell, the wind is almost directly behind us varying from 15 to 20 knots and shifting about 20 degrees left to right, the boat speed is ranging from 8 – 10+ kts. in response to the varying wind pressure, shifting angle and falling off or over the swell or actually catching a wave and surfing down the swell. Our navigator has set a course with a very narrow range of shift meaning that as the helmsman you spend your time chasing the wanted bearing back and forth on the compass. Responding to the wind shift, swell activity and speed changes caused by wind and surfing. A three hour watch with two persons requires the full concentration of the helmsman; it seems this is why we have happy hour, so that stories can be told without losing control. Thank goodness for six hours of sleep. And than of course you get the old salts on the tiller that make it look simple, subtle shifts of the tiller as if they know where the boat wants to go before it goes there, off that wave with the wind shift and the change in speed. As an analogy, take a 2 foot piece of line not too stiff but not too soft and with one eye closed PUSH it across the kitchen floor around a table leg and out the door. Of course if you try this at home ensure that the neighbors aren’t watching.

“WE” Brian Samuel Allott

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