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J/24 Europameisterschaft race, 2007
J 24 blue.svg
Class symbol
Current specifications
Crew 3 – 5
Type Monohull
Design One-Design
Construction GRP
Rig Fractional rig
Keel Fixed
LOA 7.32 m (24.0 ft)
LWL 6.10 m (20.0 ft)
Beam 2.71 m (8 ft 11 in)
Draft 1.22 m (4 ft 0 in)
Hull weight 1,406 kg (3,100 lb)
Mainsail area 12.68 m2 (136.5 sq ft)
Jib / Genoa area 11.58 m2 (124.6 sq ft)
Spinnaker area 41.7 m2 (449 sq ft)
Year 1977
Designer Rod Johnstone
Infobox last updated: 30/01/2013

The J/24 is an international One-Design keelboat class as defined by the International Sailing Federation.[1] The J/24 was created to fulfill the diverse needs of recreational sailors such as cruising, one design racing, day sailing, and handicap racing.[2]

The J/24 class has more than 50,000 people sailing 5,300 boats worldwide; is established in nearly 40 countries with well over 150 active fleets; and is still considered the "gold standard" for modern one-design keelboats around the world. It is the world's most popular One-Design keelboat as measured by hulls produced.[3][4][5][6][7][8]


In the summer of 1975 Rodney Johnstone designed and built hull number 1 in his garage in Stonington, Connecticut. "Ragtime" would serve as the master mould for the subsequent hulls. This design allowed him to start the very successful J-Boat company with his brother Bob Johnstone. By 1978 the class was popular enough to hold a one-design regatta in Key West with twenty boats on the line.[citation needed]

Early boats (hull numbers up to 3000) need a lot of work to rebuild their keel shape (move material forward) to make them point and sail fast in light wind. These older boats can be modified if one wants a competitive J/24. New boat manufacturing is done by multiple companies around the world in France, USA, Italy and Argentina.[9] In the US, J/24's are built by US Watercraft.

As of January 2009, approximately 5,475[10] J/24s have been produced. Approximately 20 new boats were produced in 2008. The average price of a complete, new boat without sails was approximately £20,000.[10]

Authority, rules and regulations[edit]

The international authority for the class is the ISAF, which shall cooperate with the International J/24 Class Association on all matters regarding these rules. Interpretations of these rules shall be made by the ISAF, which in coming to its decision may consult the International J/24 Class Association and the copyright holder.[2]

The International J24 Class Association (IJCA) has the sole authority worldwide for the conduct and management of the International J/24 Class. The IJCA Constitution, the By-laws and other regulations are binding on all members, and all registered J/24s shall conform to Class Rules and any limitations imposed by the IJCA and ISAF.[11] IJCA is a "not-for-profit" organization.

Current rules (as well as the history of changes) for the International J/24 Class is available from the International Sailing Federation web site[12]

Crew requirements[edit]

J/24s are usually raced with a crew of five, but class rules require only that there be at least three crew, with a total combined weight under 882 lbs (400 kg).

Reasons for the J/24's popularity[edit]

The J/24 is no longer considered the most modern sailboat in its class, but it is still a very popular sailboat among keel boat racers. While some of the world's best J/24 sailors have the latest version J/24, a well-prepared 1977 model, built to the same shape and weight with rigid end-grained balsa core construction can still win sailing the class world championship even after 30,000+ miles of trailering.[3] This is one of the many advantages of One-Design sailing that the J/24 is benefitting from.

Another reason for its popularity is that it is fairly easy and inexpensive to acquire a used boat and gear due to the large number of boats produced. There are 136 active fleets in the US alone,[13] which offer a lot of race competition. This makes the J/24 a popular boat for beginners and experienced sailors.

J24 sailing downwind in San Francisco bay

Mast Tuning[edit]

In a series of videos Mike Ingham of North Sails describes the boat as being designed a bit wrong with the mast too far forward (3") relative to the keel. This results in lee helm in light wind condition. "Everything is about getting the mast aft" says Ingham.[14] Racing regulations set the maximum length of the forestay and the location of the mast on the deck. Therefore, latest thinking is to shorten the mast so that it can be raked backwards and still have the same forestay length. This type of tuning on a J-24 is described as min-mast. Moving the mast on the deck backwards, as in aft-mast rigs, isn't legal as the position of the mast on the deck is set by regulation. Mast butt position should be adjusted so mast pre-bend matches luff curve on the main and gives right tension on the frontstay (which is fixed length) to match jib hollow of the genoa.

See also[edit]


  1. ^ "Classes and Equipment: J/24". International Sailing Federation. 
  2. ^ a b "J24 Class Rules effective March 1, 2009" (PDF). J24 Class Association. 
  3. ^ a b "J24 History". J24 Class Association. 
  4. ^ "Royal Motor Yacht Club / J24". Royal Motor Yacht Club UK. 
  5. ^ "Comhem Sweden". Comhem Sweden. 
  6. ^ "J24 Worlds – World-class Sailing on World-class Banderas Bay". Puerto Vallarta news. 
  7. ^ "UK J 24 Class Association". Sailing Networks. 
  8. ^ "J24". JBoats Southwest. 
  9. ^ "J/Builders". J/Boat web site - J/Builders. 
  10. ^ a b "2009 CLASS REPORT, International J/24 Class Association" (PDF). International Sailing Federation. 
  11. ^ "IJCA Constitution, Revised August, 2006". International J24 Class Association. 
  12. ^ "Class Rules J/24". International Sailing Federation. 
  13. ^ "US Fleets". J/24 USA Class Association. 
  14. ^ "J-24 Tuning and Sail Trim Part 2 - Mast Balance". Mike Ingham, North Sails. 

External links[edit]