Perry Design Review: J/24

There have been many boats over the past 20 years that have left an impact on sailing, but few have carried with them the shockwave of the J/24. The J/24 was so successful that it spawned J Boats ranging from the 24 to the 40. There are also numerous clones on the market. More than a type of boat, the J/24 represents a style of sailing.

A J/24 sails upwind under main and small jib. Photo courtesy JBoats.

As the IOR gathered momentum, boats like the Ranger 33 were pushed aside and the only viable weapon on the race course was a boat specifically designed to exploit the complex IOR measurement system. This in itself was predictable; after all, the IOR was never intended to be a handicap rule. The problem started when the IOR boats began approaching the extremes. Today's IOR boat is a fairly subdued yacht compared with the contorted IOR boats of 10 years ago. The emphasis was squarely on rated speed and boat speed for a given length was irrelevant. By the time this approach was contracted down to the Quarter Ton level, the boats began to get a little radical. The pinched end that worked on the Two Tonner gave us a tiny stern and midget cockpit on the Quarter Tonner.

Well along came this guy, Rod Johnstone, who was partially through a correspondence school for yacht design. He wanted to have a good all-around boat that he could race under various local rules, particularly the MORC rule. The boat was fast and Johnstone blew away the local competition. In 1975 he won the MORC National Championship with John Kolius placing second. Before long J/24s were in production and dominating MORC fleets everywhere.

This continued to such a degree that the natural extension was a one-design fleet. This particular aspect of the J/24's success was expertly orchestrated with the best modern advertising methods. It worked. The Johnstone and his brother had and exceptional boat that met with exceptional success. The J/24 could demolish the hottest Quarter Tonner and compete very successfully with the best Half Tonners. The Johnstone brothers have sold more than 4,300 J/24s, and it is now the largest one-design keelboat class in the world.

There are two key areas to this success. The first is pure boat speed. The J/24 is a stiff boat with lots of horsepower and sailing length. The hull lines are very clean and wetter surface is at a minimum. The J/24 is not an ultra-light. It has a D/L ratio of 150, which puts it just on the edge of "medium." This has the advantage over the ULDB approach of giving the boat sufficient displacement for good sail carrying power. J/24s love a breeze upwind or down. The J can carry a full main comfortably up to 20 knots true wind speed. The keel is a fairly high-aspect-ratio keel and the rudder is outboard with no balance at all. There is some flare to the topsides, and overall I'd say that this is a very attractive hull shape.

The general deck configuration and rig is the second area that has contribution to the 24's success. The key here is simplicity, and this translates into the most knots for the buck. The fractional rig combined with the powerful hull minimizes sail inventory, and the strict one-design organization limits sophisticated deck gear. The sweptback spreaders eliminate the need for runner. The plain, flush deck leaves lots of room for a racing crew of four or five. The J/24 is a lot more fun to sail than the typical Quarter Tonner.

The J/24 is the boat that I chose to teach my sons sailboat racing.

Boat Specifications