# 2.4 Metre (keelboat)

Current Specifications
File:2.4.jpg
International 2.4mR
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Class Symbol
Crew 1
LOA 4.16 m (13 ft 8 in) (Mark III)
Beam 0.805 m (2 ft 7.7 in)
Draft 1 m (Template:Convert/And0) (Mark III)
Hull weight 260 kg (570 lb)
Mast height 4.65 m (15.3 ft)
Main & Jib area 7.5 m2 (81 sq ft) (Mark III)
Infobox last updated: 15 August 2009[1][2]
Paralympics Class

The International 2.4mR is a one-person keelboat. The class is a design class governed by the 2.4mR rule. The rule is controlled by the International Sailing Federation (ISAF) since it is one of few classes designated as an International class. The class rule is closely related to the 12mR rule that was used in the America's Cup and the shape often resembles the larger sister.

The class is often perceived as a one design class since the dominating sailors all use the Norlin Mark III designed by yacht designer Peter Norlin of Sweden.

The boat is primarily used for racing and the class holds highly competitive national events in many countries. World and European championships (only when the World Championship is not in Europe) are attracting around 100 boats every year. In some countries however it is looked on as a Paralympic class only and consequently the level of racing are lower in these countries.

2.4mR has been a Paralympic class since 2000 and is ideal for handicap integrated sailing since the sailor does not move in the boat, and everything is adjustable from right in front of the sailor. Both hand-steering and foot-steering are possible. The boat's ability in integrated sailing has been proven on the result lists of several World Championships. In 2002 and 2005 there were handicapped World Champions. The boat is sailed without a spinnaker, but with a whisker-pole for the jib.

## History

After the 1980 America's Cup, people in the Newport, RI area started sailing boats called Mini-12s named for the 12-Meter Yachts used in the America's Cup. As the class developed, word of it spread to Sweden, home of yacht designer Peter Norlin. Norlin tweaked the design, and along with other naval architects he created the 2.4 meter yacht class. Although the 2.4mR is a construction class, Peter Norlin is in practice the totally dominating designer, and the class is therefore often mistaken as a one design class. In addition to all the sailing aspects of the boat, Norlin has worked the design to incorporate features for the physically disabled to use the boat.

## Rating formula

As an open class rather than a one-design, all boat designs must meet the following formula.[1]

$R = \dfrac{L + 2d - F + \sqrt{S}}{2.37}$

Where (all measurements in mm)

• L = the length of the hull (see rule D.6.3)
• d = the midship girh difference (see rule D.6.4)
• F = the freeboard height (see rule D.6.5)
• S = the total area of the mainsail and jib combined.