quote:
Originally posted by yoyo
It is in the afternoon session with less wind and quieter water than when they set their fast times.
Apparently this is choppy for SP... or maybe that was the morning session where they said that.??
The incoming tide (ie: the afternoon for that day) generates what we call "whoop-de-doo's" - basically a bit like small swell, where the crest-to-crest length is about 4-5m or so, and can get to about 30cm of height.
The PiT gets quite a bit of chop, starting at about 10m from the shore (on the fastest part of the speed course - not near the start of the run). When it is really windy (say 30+), you get chop 50cm or more with a separation of about 1m, and very steep.
And... depending on the wind direction, you get swell build up due to the wind. It gets worse on a broad (read: westerly) direction, as you reach the fastest part of the course, just as the wind has had a few hundred meters to build up rolling swell. The wavelength tends to be about the same as the whoop-de-doos.
So one of the "go fast" tricks, is to sail under 5m from the sand bank so as to avoid the short-sharp chop, leaving you to deal with the whoop-de-doos and wind-swell. So at 40+, you are doing about 20m/s, which means that you are hitting a few crests per second.
Since there is no way to react to the water state at that rate, crashing is a serious possibility, especially when you reduce mast-foot pressure while trying to slow down. ie: its quite normal to see people crash at the end of the course as they slow down to around the 30kn mark.