A British team is on course to break one of the last great speed records. Piloting a yacht that looks like a futuristic windsurf on steroids, the team hopes to achieve the world sailing speed record in the next few weeks, with an average speed higher than 50.57 knots (the existing record).

That is the equivalent of nearly 60mph — no mean feat for a contraption that’s bonded together from bits of carbon fibre and plastic.

If the team manages to set the record, it will mark the culmination of seven years of work on a prototype vessel — called SailRocket — that could pave the way for even more extreme speeds in the future. And it has all been accomplished on a shoestring budget, relying on help donated by UK companies plus a generous dash of typical British thirst for adventure.

The team is now doing trial runs off the Skeleton Coast in Namibia — last week it hit 42 knots. It now plans to increase speeds gradually throughout March until it hits the record-breaking speed.

“Trying to become the fastest in the world always has its ups and downs,” says Paul Larsen, the pilot (note that he doesn’t describe himself either as a sailor or as a yachtsman).

“It’s the sailing equivalent of drag racing — I’m really just sitting in the boat and hanging on. It’s a point-and-shoot thing — I just hold my breath and count to 20.”

The team already knows what it is like to push the boundaries of speed on the ocean and fail. In December, the yacht crashed spectacularly during an attempt on the record, when the nose suddenly lifted and flipped the Vesatas SailRocket into the air, causing it to do a loop-the-loop at nearly 60mph.

“It was totally unexpected,” says Larsen, describing it as his Donald Campbell moment. “One minute I’m charged full of adrenaline, thinking I’m about to achieve a lifetime goal . . . and then in a few seconds I’m upside down in the air. It’s like being in a rally car and then, all of a sudden, you drive off a cliff.”

Measuring nine metres in length, the SailRocket has room for just one person on board, who controls the yacht from a roll cage in the back of a torpedo-shaped fuselage.

The sail (or, more accurately, wing) of the vessel is made from a combination of carbon fibre and glass fibre to maximise stiffness while keeping the weight low.

The really clever thing about the SailRocket, though, is its radical new layout: rather than the wing being attached to the hull in the conventional way, it is placed on the leeward side, several metres from the fuselage, and connected by a carbon-fibre beam. This design eliminates the need for ballast, which stabilises boats but also slows them down (see illustration).

The SailRocket can stay stable and upright without ballast because it harnesses two competing forces: by placing the wing on the leeward side and a hydrofoil or downward fin on the other side, it exploits the opposing forces of wind and water in a tug-of-war. Uniquely in yacht design, this keeps the boat level — it does not heel or tip like other boats — so it can take greater forces and go faster. Larsen, from Australia, describes it as like squeezing a lemon pip between thumb and forefinger: “While the forces are opposing, the pip gets shot out forward.”

The revolutionary design is the brainchild of Malcolm Barnsley, 52, a naval architect from Southampton. He’s been dreaming about building the fastest sailing boat since his twenties.

“One of the beautiful things about speed sailing is that the rules are almost nonexistent,” he says. “There’s almost complete freedom, design-wise, which is the very opposite of Formula One. It’s a beautiful blank canvas with the elements of wind and water, and all you’ve got to do is convert that into speed. It is like saying, instead of a 1-litre engine, you can have a 6-litre engine at no extra cost.

“It’s the first boat to successfully exploit this concept,” Barnsley continues. “We expect to break the record in the next month.”

The waters off Namibia’s coast are perfect for speed sailing. Over the years they have gained a reputation as the best place in the world to hit record-breaking speeds, an aquatic version of the Bonneville salt flats in Utah, which have become synonymous with land speed record attempts. The last three world sailing speed records have been set there, most recently by Alexandre Caizergues of France, who averaged 50.57 knots over 500 metres.

Those records, however, were set by kiteboards; the SailRocket is attempting to be the first boat to break the record. The team almost managed it back in December, before the crash ended any hopes of continuing: SailRocket had already reached a top speed of 52.26 knots (60mph), but over the specified 500-metre course it managed an average of only 47.36 knots (54mph) — enough to claim a new unofficial record as the world’s fastest sailing boat, but 3.22 knots too slow to claim the outright speed record.

Then, two weeks after the crash, Macquarie Innovations, an Australian team, snatched away the fastest boat title by averaging 48.11 knots. The outright record attempt is now a three-way race between the Australians, the British and the Frenchman Alain Thébault, 45, who reached 52 knots in his trimaran Hydroptère last year, albeit over a shorter distance that did not qualify for a record.

The team says the efficiency of its design gives it an advantage over its rivals: to reach 50 knots it requires just 22 knots of wind, whereas the French boat needs 35-knot winds and kitesurfers need a 50-knot wind.

If they are right, it will be a tribute to what clever engineering can do on a tiny budget. Larsen and Barnsley (since joined by a nine-strong team) first joined forces in 2001 in Woolston, Southampton, and launched their first version of the SailRocket three years later. Like the Spitfire — another great British design built in Woolston — the boat features an elliptical wing to increase speed and efficiency.

Today, the sixth generation of the boat is estimated to be worth £250,000, although Barnsley says it was built for less, as local companies gave services for free and engineers volunteered for the project. Compared with the millions spent on international yacht racing, the SailRocket is a veritable bargain.

“It feels like we’re playing with the first jet engine,” says Larsen. “Once we have perfected it, who knows how fast we can go?”

A 60mph balancing act - how the sailrocket works

Conventional yachts use ballast to resist the overturning effects of the sail, but this slows them down.

The Vestas SailRocket doesn’t have ballast and instead relies on the competing forces of wind (red arrow) and water (blue arrow) to keep it stable and provide forward propulsion (green arrow).

This means positioning the sail (1) at a precise angle, leaning into the wind. The hydrofoil (2), which is a metre long, is positioned at the same angle, in the opposite direction, under the water, and the two are separated by a carbon-fibre beam (3) of a precisely calculated length.

The result is acceleration of 10 knots per second — similar to that of a sports car — and a proven top speed of 52 knots, about 60mph.

The pilot (4) has an aerodynamic helmet and controls the craft’s rudder, as well as the angle of the sail and the hydrofoil, with pedals in the cockpit. Two computer screens allow him to monitor the angles of the sail and the hydrofoil.