New keel proves more trouble than it's worth

SAILING: New-fangled technology designed to give an edge in last year's Commodore's Cup has already gone overboard in Cork this…

SAILING:New-fangled technology designed to give an edge in last year's Commodore's Cup has already gone overboard in Cork this season in favour of a conventional method.

Following a debut season of mixed performances on the 37­foot Jump Juice, Conor Phelan went back to the drawing board for 2007, removing the trim tabbed keel and replacing it with with a traditional, fixed fin keel.

The technology is in poplar use in America's Cup boats, but is new to smaller racing boats.

Based on a development of the Ker 36, Phelan's boat has a similar layout, though it was originally fitted with a trim tabbed keel to maximise her IRC competitiveness and take her to the top of the rating band for Class Two in the Commodore's Cup.

READ MORE

The Royal Cork crew found that, in flat water with strong breezes, the tab worked as well as the computer model suggested, but as soon as there was any kind of choppy sea the tab became more of a hindrance than a help.

"As soon as it got sloppy it became really difficult to keep the boat in the groove," according to Mark Mansfield, Phelan's helmsman.

The trim tab is a "flap" - like the flap on the trailing edge of an airplane wing - hinged to the trailing edge of the keel.

When the boat tacks, the tab is swung from one side to the other, around 5-12 degrees either side of centreline. This gives the keel an asymmetric shape that produces more lift.

It also produces more drag, but if designed and used correctly, the extra drag is more than offset by lift - meaning the boat goes forward more and sideways less.

Last month Phelan (steering) and Mansfield (on tactics) raced in Kinsale's Matthews Chandlery-sponsored league and won, counting four straight firsts in a testing range of conditions against their Commodore's Cup team-mates.

Reverting to a normal keel configuration now, the Jump Juice crew say they are as quick, if not quicker. It's also easier, says Mansfield, to stay in the groove.

The removal of the trim tab has also given them a handicap advantage of 40 seconds in the hour, a significant saving at Commodore's Cup level.

The results and the modifications have provided plenty to chew over, given that this week's meeting of owners for the 2008 Commodore's Cup revealed several are already considering new builds.

Juice will be among a strong Cork representation in Class Zero at Volvo Dun Laoghaire Week in eight weeks, where entries are expected to reach 300 by next Monday when the early entry discount closes.

A feature of the regatta is the first appearance on Irish waters of the TP52s - three have entered the Super 0 division with the news that top Irish skipper Colm Barrington has acquired Flash Glove and will race against Paul Winkelmann's Island Fling from Hong Kong and Benny Kelly's Panthera from Royal Corinthian YC.

David O'Brien

David O'Brien

David O'Brien, a contributor to The Irish Times, is a former world Fireball sailing champion and represented Ireland in the Star keelboat at the 2000 Olympics