Jacksnipe (dinghy)
Encyclopedia
The Jacksnipe is a two-man racing sailing dinghy
Dinghy sailing
Dinghy sailing is the activity of sailing small boats by using five essential controls:* the sails* the foils ....

 with a single trapeze
Trapeze (sailing)
In sailing, the trapeze refers to a wire that comes from a point high on the mast, usually where the shrouds are fixed, to a hook on the crew member's harness at approximately waist level...

 for the crew and symmetrical spinnaker
Spinnaker
A spinnaker is a special type of sail that is designed specifically for sailing off the wind from a reaching course to a downwind, i.e. with the wind 90°–180° off the bow. The spinnaker fills with wind and balloons out in front of the boat when it is deployed, called flying. It is constructed of...

.

History and description

In the late 1960s, Jack Holt
Jack Holt (dinghy designer)
Jack Holt, OBE was a prolific designer of sailing dinghies. His pioneering designs of dingies using plywood did much to popularise the sport of sailing in the period immediately following World War II....

 was asked by Peter Harris of the British Snipe Class Association to design an up-to-the-minute boat with a hull the same overall length as the International Snipe
Snipe (dinghy)
The Snipe is a foot, 2 person, one design racing dinghy. Designed by William Crosby in 1931, it has evolved into a modern, tactical racing dinghy with fleets around the world. The Snipe is simple, making it easy to sail and trailer. The boat is recognized by the International Sailing Federation as...

, which would carry the Snipe rig with the addition of a trapeze and spinnaker. The Snipe having failed to be selected for Olympic Games, it was hoped that a modern, high-performance boat might succeed.

At the time, scows were very much the thing, especially the Fireball
Fireball (dinghy)
Originally designed by Peter Milne in 1962, the Fireball is a one-design high-performance sailing dinghy. The Fireball is sailed by a crew of two, and sports a single trapeze, symmetric spinnaker and chined hull. The class is strictly controlled, but has adapted to advances in building techniques...

, and so Holt drew up a flat-bottomed planing
Planing (sailing)
Planing is the mode of operation for a waterborne craft in which its weight is predominantly supported by hydrodynamic lift, rather than hydrostatic lift .-History:...

 design, considerably lighter than the International Snipe, with a pivoting centreboard
Centreboard
A centreboard or centerboard is a retractable keel which pivots out of a slot in the hull of a sailboat, known as a centreboard trunk or centerboard case...

 and a bold new cockpit design that still looks contemporary 40 years later. The name was suggested by Peter Scott.

The cockpit includes a double bottom (or false floor) which extends through almost to the bow, with deep, self-bailer equipped footwells each side of the centreline; a detachable foredeck was developed but has not been a feature of production boats. While the production deck, which extends well forward of the forestay fitting, would lend itself very well to incorporation of a spinnaker chute, none was ever fitted by the manufacturers, spinnaker stowage relying instead on an elasticated pocket or 'turtle' before the mast, under which the spinnaker could readily be stuffed.

At the time, the Class Secretary commented:

This exciting new design incorporates all modern features. The easily driven, lightweight hull planes readily yet possesses fantastic stability. Fully equipped she is priced considerably below other high-performance dinghies. Her round bilged hull, designed with glass fibre in mind, has a double bottom, self-draining through transom flaps and wells for helmsman and crew equipped with self bailers. The ample built-in buoyancy and reserve foam buoyancy is designed to make self rescue easy in the case of capsize.

The claims made were by no means excessive. The buoyancy arrangements are exemplary, allowing the boat to float low on its side when capsized making it easy for the crew to climb onto the centreboard and, in combination with a foam-filled mast, making it rare for the boat to fully invert. Yet the double floor provides for very rapid expulsion of any water in the cockpit after the boat is righted; a combination of virtues that few other designs can match. The deep footwells improve the boat's stability by positioning the crew low during manoeuvres, such as gybing, greatly adding to confidence.

A singlehanded option was envisaged, with a forward mast step position, a second, forward set of chainplates, and corresponding set of anchor points for the mainsheet bridle. With a longer tiller extension, the boat could then be sailed using just the mainsail and trapeze, Contender-style.

By comparison with its main rivals, the Fireball
Fireball (dinghy)
Originally designed by Peter Milne in 1962, the Fireball is a one-design high-performance sailing dinghy. The Fireball is sailed by a crew of two, and sports a single trapeze, symmetric spinnaker and chined hull. The class is strictly controlled, but has adapted to advances in building techniques...

 and Hornet
Hornet (dinghy)
The Hornet dinghy is a 16 foot high performance dinghy designed by Jack Holt in 1952.It is sailed by two people, with either a sliding seat or a single trapeze, or where neither plank nor trapeze is fitted, by three people...

, the Jacksnipe is lightly canvassed, which makes it ideal for lighter crews, but this combined with the large underwater planing surfaces leads to a boat which performs better in stronger than in lighter winds - a characteristic of many later 'skiff' designs. In overall performance terms, the Portsmouth Yardstick
Portsmouth yardstick
The Portsmouth Yardstick or Portsmouth handicap scheme is a system of handicapping used primarily in small-boat yacht racing.The handicap is applied to the time taken to sail any course, and the corrected time can be used to compare widely different sailboats on even terms. Portsmouth Numbers are...

 in 1970 was 88, which compared to 85 for the Fireball and 88 for the Hornet (at the time in its original form with jib rather than genoa, and a small spinnaker).
Some 32 examples were built by Jack Holt Limited, moulded by Lakeland Plastics before the design was passed to a chandlery which tried fitting 505
505 (dinghy)
The International 505 is a one-design high-performance two-person monohull planing centerboard dinghy, with spinnaker, utilizing a trapeze for the crew...

 rigs to the hulls, resulting in a very fast (talk at the time was of speeds approaching those of an A-Class catamaran) but presumably over-canvass
Over-canvassed sailing
A sailing boat that is carrying too much sail for the current wind conditions is said to be over-canvassed. An over-canvassed boat, whether a dinghy, a yacht or a sailing ship, is difficult to steer and control and tends to heel or roll too much...

ed boat, bearing in mind the narrow overall beam. A Fireball rig would surely have been more appropriate.

That the class failed to sell in large numbers can be attributed to stiff competition offered by the already well-established Fireball, and, ironically, to antipathy from within the British Snipe Class which had sponsored the new design but was split as to whether it would be detrimental to the popularity of the existing design (see ref 1).

Of current designs, the closest in terms of dimensions, cockpit layout, performance, ideal crew weight and sailing qualities is the 3000
3000 (dinghy)
The 3000 is a racing sailing dinghy crewed by two persons with a trapeze for the crew. Launched in 1996 as the Laser 3000, the 3000 was developed from the Laser 2, using the original Frank Bethwaite-designed planing hull combined with a brand new self-draining deck by Derek Clark...

.

External links

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