From the following Sail-World article:
Glenn Ashby describes his job as wing trimmer on Emirates Team NZ's AC72 as a
bit like driving a truck.
The multiple A-Cat world champion, Olympic
Silver medalist, and former Tornado cat world champion, is talking a really big
truck with a 32-speed gearbox as it traveling up and down a series of hills and
The driver, he says, must always
think ahead, two or three moves ahead. And that’s what he does on board the
Glenn’s changing gears (adjusting the wing trim) almost
constantly. Either driving a truck and trimming the wingsheet, or with the
hydraulics, so there’s never a time when he’s not thinking, looking for the
breeze ahead and changes in wind patterns – thinking about the next gear change
to achieve best performance.
The wing is set up differently for
different modes – upwind a low fast mode or high, slower mode for instance.
Racing downwind, the wing set up has a huge influence on the boat’s performance
and must be used accurately with the front sails, making for dozens of small
adjustments throughout the leg.
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