The present invention relates to sail boats and, more particularly, to a sailing frame that is adapted to be mounted on a floating, buoyant hull structure.
It has long been known that most boats can be converted to sail boats by the addition of an apppropriate mast structure to support a sail and by the addition of appropriate stabilizing fins or boards which extend below the water line to impart a certain fore and aft stability to the boat to provide some slight increase in the resistance of the boat to rotation about the longitudinal axis.
Conventionally, when one starts with a rigid hull, one finds ample structural support for the addition of the mast and the stabilizing fins. Mast can be supported by a keel or, where absent, by the relatively rigid sole of the boat, while the gunwales provide points of attachment for stays which can support the mast upright through tension.
Either center boards or dagger boards are readily mounted and find adequate points of attachment on the structure. Even canoes can be fitted with a kit that includes a pair of lee boards and a central member joining the lee boards which includes a mast mount for supporting a mast structure. A rudder assembly, when added, adapts the canoe for sailing.
Since the 1940's, inflatable boats have achieved more and more popularity. These inflatable boats, which during the war were utilized as life rafts or as dinghies have been improved and developed to the point where they are currently being sold, for example, by Avon Inflatables, Limited, of Great Britain. The Avon catalog includes dinghies in sizes from 8 feet to 12 feet in length; sport boats which are adapted to operate with outboard motors, as well as rigid inflatables, which include a fiber glass rigid hull. The sport boats range in length from 9 feet to 16 feet and the rigid hull versions range from 13 to almost 18 feet.
A common feature shared by the inflatables is the substantially planar sole or floor which is made of a fluid impermeable flexible sheet. In a better inflatables, a plastic impregnated fabric is used, while less sturdy versions utilize a heavy guage film such as P.V.C. A substantially cylindrical inflation tube provides buoyancy and also serves as the "hull" of the craft. The buoyancy tubes can be fitted with oar locks, outboard beckets and life lines. The buoyancy tubes can be subdivided or compartmentalized for safety so that a rupture need not cause the loss of all buoyancy.
Another feature of the inflatable boats in their substantial resistance to capsizing, resulting from rotation about a longitudinal axis. Further, due to the wide beam and low center of gravity, the boats are extremely stable.
The very flat bottom of the inflatable, while of great benefit in assuring stability and resistance to capsizing does subject the boat to "skidding" under the force of the winds or waves. This tends to make rowing slightly more difficult since the craft is very sensitive to unequal application of propelling forces by the oars.
Because the inflatable is not rigid and, on the contrary, is resilient and flexible, no serious efforts have been made to adapt the craft for sail. Therefore, sailing for pleasure creates an additional category of uses for inflatables.
Inflatable boats have also achieved widespread acceptance and distribution as life rafts for aircraft and marine vessels. In such cases, they are compact, easily stored, easily deployed and, using compressed gas cylinders, easily inflated. In recent years, inflatables used as life rafts have been modified to a circular or polygonal shape and have been fitted with all types of survival gear. However, as noted above, such a structure is not easily propelled or directed and, in use, would generally drift aimlessly at the mercy of the winds, waves, and prevailing currents.
Oars or paddles can be employed for limited, directed movement. Sea anchors can limit the drift due to wind, while sails can accentuate the effect of the wind and minimize the drift due to waves and current.
With a suitable sailing adaptation, the wind could be utilized to propel the craft on a reasonably predictable course and the crudest or navigational instruments would permit progress in a desired direction, without the physical exertion required by rowing.
Frequently, occupants of a life raft do have an idea of their location and the ability to navigate. Under such circumstances, it would be highly desirable to have the capability of directed progress toward a destination whether it be land, a well-travelled shipping lane, or an airline route. Accordingly, a sailing "kit" adapting the raft to be sailed would be an invaluable addition to the raft itself.