Capt. JG wrote:

"KLC Lewis" wrote in message
et...

"Gogarty" wrote in message
news
I have been doing a lot of Googling but I can;t find an answer.

You have no doubt noticed that the sails on the current crop of
America's Cup challengers are not triangular -- even with a huge roach
-- but trapezoidal. How do they maintain that shape at the head? Is
there a gaff at the head parallel to the boom? How do they keep the head
of the sail from falling way off to leward? Is there some arrangment of
masthead sheets that keep the head parallel to the boom?


It looked to me like there's a gaff, of sorts, at the headboard.

Square or rectangular cross-section battens:
http://na.northsails.com/northenews/March07.htm

Is that what they're calling a "flipper" or "flopper"? I seem to recall a
name like that.

Flippers or batwings are to help support the top of the genoa, sort of
like an external batten. See: http://snipurl.com/1lfl1

DT