Setting starting line bias

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This is a line-setting device I fabricated for the recent UK IOM National Championships, where I was the Race Officer.  The idea is that the set of the start line is taken at an angle of 85 degrees to the incident wind to give an appropriate line bias at the pin or port end of the start.  So the device features a plastic protractor and a couple of knitting needles tied to it, with an angle of 85 degrees between the knitting needles.  The wind gauge fits into the top of a wooden handle, and when the tip of the wind gauge coincides with the forward-pointing needle, the line bias can be set by sighting the start line buoys along the other needle.

Update:  Following a Regional Race Officers' seminar run by the RYA in Lymington in 2010, current best practice is for a Race Officer to set the start line in two stages.

The first set is at right angles to the wind (or at 85 degrees to give a little starting out port-end bias).

The second, and more important, set is to observe what the competitors do, and make the necessary adjustment.  If they bunch at the pin, drop the pin;  if they bunch at the starboard end, raise the pin;  and know that the line is set just fine when there is no bunching.  That's it.  Oh -- raise or lower the pin by as much as it takes to get the boats spread out along the line, without getting worried at all about the amount of movement you have to make in the line...

Another point worth making here is that current ISAF and RYA best practice is to make sure that the line length is equal to 130% or 150% of the total lengths of the boats expected at the start.  Not less...

2010-05-03


2011 Lester Gilbert