A boat that was not designed to sail
Most inflatable boats were built as tenders, rescue craft or military boats and were driven by paddles, oars or small engines. Putting a sail on one raises a basic problem. A sailing boat needs to resist being pushed sideways by the wind, and an inflatable has no keel and a flat or slightly shaped soft bottom. Without something to resist sideways drift, it will mainly be blown downwind. Sailing inflatables therefore tend to use leeboards (boards hung over the side), daggerboards slotted through the hull, or a small fixed fin to give the hull some grip on the water.
Bombard and L’Hérétique
The best-known sailing inflatable is the boat in which the French doctor Alain Bombard crossed the Atlantic in 1952. He named it L’Hérétique, a name that reflected his rejection of the accepted view that castaways could not survive for long at sea. The boat was a small inflatable made by the French company Zodiac, fitted with a modest sail so that it could make progress with the trade winds. Bombard travelled from the Canary Islands to the Caribbean island of Barbados, a voyage that reportedly took about two months.
The purpose of the trip was not sailing for its own sake. Bombard wanted to show that a shipwreck survivor could live on fish, plankton and a limited amount of sea water, an idea that many medical authorities doubted. His claims about his health and diet during the voyage have been debated, and it would be wrong to treat the trip as proof that drinking sea water is safe. As a piece of maritime history, however, it demonstrated that a small inflatable could make a long ocean passage under sail, and the story did much to publicise inflatable boats in France and beyond. The wider background of such voyages appears in the history of Atlantic crossings.
From stunt to everyday boat
After Bombard, manufacturers recognised that a sail kit was a natural extension of the inflatable dinghy. During the 1950s and 1960s, various companies in France, Britain and other countries sold small inflatables with mast sockets, simple sail plans and leeboards or daggerboards. The aim was a boat that could be carried in a car boot, inflated at a beach or lake, and sailed for fun.
The typical rig was small and simple. A single mast carried a mainsail, sometimes with a small jib, and the mast was held up by lines running to the hull. Some boats used a sprit or leg-of-mutton sail, designs that avoid a long boom. Their sail design drew on ideas used in other small boats, in the same way as the broader history of sailboat design had always borrowed from one type to another.
Performance, as a rule, was modest. A soft hull flexes, a tube-shaped bow throws spray, and the lack of a keel limits how well the boat can sail upwind. These boats were not generally thought of as racing craft. They were suited to sheltered water, holiday use and teaching beginners, and some were used in sailing clubs and youth programmes where storage and cost mattered.
Variations
Some designers pushed the idea further. Inflatable catamarans and trimarans were produced in various forms, using inflated hulls joined by a frame. The principle was the same as in rigid multihulls, such as the Hobie catamarans that popularised beach sailing in later decades, but with hulls that could be deflated and folded. These remained niche products.
Another related development was the sailing rig for inflatable kayaks. The principles overlapped with those discussed under kayak sail rigs, where a small sail is added to a paddled boat to assist on downwind legs. In both cases the sail was an aid for travelling with the wind rather than a full replacement for paddles.
Yet another variation was the lifeboat or liferaft with a sail. Some lifesaving rafts and boats carried small sails as part of their emergency equipment, so that survivors could make some way towards land. These were intended to extend options in an emergency and were not designed as pleasure boats.
Limits and later history
As engines and rigid-hulled inflatables came to dominate the market from the 1970s, sailing inflatables became a specialised corner. The development of cheap, light outboard motors made the motor tender more attractive than a sail kit for most buyers, and small rigid sailing dinghies, including plastic ones, offered better performance at moderate cost. Even so, sailing inflatables have remained available, and enthusiasts continue to produce, adapt and cruise in them.
What the history shows
The sailing inflatable is best understood as a niche rather than a distinct class. Its story begins with a single famous voyage and continues through small commercial products of the middle of the twentieth century. It shows that a boat can be adapted to a purpose its designers did not intend, provided someone solves the problem of resisting sideways drift. It also shows that fame and practicality do not always go together: Bombard’s boat made headlines, but the ordinary sailing inflatable was a modest craft for sheltered water.