Basically it just puts tension on the rudder so when you uncleat the downhaul it just pops up. Here is the page from the manual:
http://www.thebeachcats.c…pictures&g2_itemId=35268
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Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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