January 15, 2003
Source: www.lvcup.com

Ken McAlpine clarifies seven questions in connection with close hull appendages

[Editor's Note: To view and learn more about the "Hula," see the article What's "Down Under" On Each AC Boat. It has photos and more comments on Unveiling Day.]

The America’s Cup Technical Director, Ken McAlpine, has issued a public interpretation clarifying a number of issues relating to the Hula appendages on Team New Zealand’s two yachts.

The interpretation is a response to seven questions put to the Measurement Committee by one of the syndicates following the unveiling of the Defender’s yachts last week.

One of the crucial issues surrounding the use of close hull appendages, like the Hula, is that they may not touch the hull outside of the permitted attachment zone during racing. One of the questions was whether material becoming lodged in the gap between the Hula and the hull would constitute touching.

McAlpine’s reply says that deliberately placing any foreign material between the hull and the appendage would contravene the rules. Accidental lodgement of materials like seaweed or debris might not contravene the rules.

He further rules that no device or contrivance can be installed to alter the gap between a hull and an appendage while the yacht is in the water.

McAlpine also notes that any competitor using a close hull appendage must initially satisfy the measurers that the appendage cannot touch the hull while racing (in order to receive a measurement certificate). “The responsibility remains with the competitor to satisfy the measurers of continuing compliance,” McAlpine says.

He adds that the touching of an appendage outside the permitted area could not be considered “normal wear and tear”.

Two questions were put regarding ACC Rule 26, which prohibits appendages or devices whose purpose is to bleed off or alter the water flow of the boundary layer. McAlpine says that subject to the limitations of Rule 26 … “there is no limitation on devices which may affect the speed of water moving between the hull and the appendage, provided the device is not movable or flexible and does not touch the hull outside the hollows permitted area whilst racing.”