Pulling a fast one

For years Nigel Macknight has dreamt of breaking the world water speed record. He is a man determined – despite the fact that four out of five previous contenders died in the attempt.

Nigel Macknight’s life changed on 2 January 1967 when, aged 11, he saw Donald Campbell’s ill-fated attempt at the world water speed record on TV. Over three and a half decades after Bluebird K7 overturned and disintegrated on Coniston Water Macknight is intent on breaking the current record by exceeding 317.60mph (511.11kph) on the same stretch of Lakeland water.

‘Campbell made an indelible impression on me,’ he says. As a teenager he approached Campbell’s chief mechanic Leo Villa and designer .

Ken Norris with the idea of making an attempt on the land speed record using a design Norris had on the drawing board. After three years he abandoned the project. ‘You need more than a dream to get it off the ground,’ he says.

Macknight went on to become a writer and publisher, racing Formula Ford and karts in his spare time. In 1991 he rekindled the dream by forming the company Quicksilver (WSR) to design, construct and mount a new attempt on the water speed record. They are up against Australian Ken Warby, holder of the record since 1978, as well as the American Challenge team.

In 1998, Macknight got into his stride with the support of a 100-strong mostly voluntary team that includes Norris. The team also had significant input from Glynne Bowsher, design engineer of Richard Noble’s land speed record-breaking Thrust SSC supersonic car. Macknight obtained sufficient sponsorship to fund design of Quicksilver, a turbofan-powered hydroplane. Model testing started as far back as 1991 and construction began last year.

Development has involved about £1.5m of sponsorship and help in kind from over 30 firms, including Corus, PTC, BOC Gases and Hexcel Composites. The project is still a struggle financially and Macknight reckons a similar sum is still needed. Despite abandoning his day job two years ago, he admits his attempt on the record is unlikely to be made until between January and March 2004.

Three years’ worth of design work in the early 1990s had to be abandoned because of the difficulty in reconciling aerodynamic and hydrodynamic performance. Early 2D design work was carried out by Glynne Bowsher using Helix, and paper drawings were then converted to ProEngineer format, creating a 3D model of the basic structure (the space-frame and representations of key assemblies, the engine, cockpit, tail and fuel tanks) for mass calculations.

The 3D model of the space-frame was fed to Elite Consulting to carry out stress analysis on a structure shell model. Elite also created versions of the upper structure, tail and sponsons (floats), front planes and sandwich panel skin for analysis, and simulated perimeter and end welds around the engine mounting and other vital positions. ‘Modelling the engine mountings was very sophisticated as the space-frame has to cope with the 11,000lb thrust generated by a Rolls-Royce Spey 101 turbofan engine,’ says Elite Consulting MD Ray Ellender. Relevant loads were applied using load cases of previous record attempts from Ken Norris.

The design went through several configurations, and is focused on a combination of speed and intrinsic safety. It is designed to be aerodynamically neutral. As a result of extensive wind tunnel tests, the vessel has a flat bottom and is slab sided, not sculpted.

Safety is a major priority, considering that 80 per cent of those involved in previous water speed records died in the attempt. Having become the first person to hold both the world land and water-speed records, Donald Campbell’s last attempt ended disastrously on the return run. Without refuelling (so the vessel was light) the boat hit wake from its first run, lifted out of the water at a speed exceeding 300mph, somersaulted and disintegrated on hitting the surface.

There was an inherent instability in Bluebird as it would ‘tramp’ from side to side, at the same time lifting its nose. It was a reverse three-pointer, with two points of contact with the water at the front and one at the back, whereas Macknight’s boat will have four points of contact and the sponsons at the back rather than the front.

Quicksilver has a broad front planing surface, which is divided into a shallow tunnel that widens the hydrodynamic footprint and aids lateral stability. It also features a computer-controlled trimming system. This uses load cell sensors in each planing shoe to measure the weight of the boat at all four points of contact with the water. The cells feed data to a central processor, which operates a hydraulic system that alters the angles of the planing shoes to adjust the trim.

‘The boat will weigh 3.5 tonnes, and we want to maintain a minimum weight on the water for positive stability,’ says Macknight. ‘If the weight drops below a predetermined figure an alert will sound and the system will automatically close the engine down.’ There is no ejector seat or parachute.

Though no previous record contenders have featured moveable ride surfaces, Macknight is confident the system will be approved by the Union Internationale Motonautique (UIM), which oversees powerboat record attempts. He insists the moveable tabs come under the category of hydrodynamic control devices. ‘If any issue arises, we will disable the ride system.’

Moveable aerodynamic surfaces are forbidden, so all control must be effected through the water.

Sheffield-based Fluent provided qualitative computational fluid dynamics (CFD) software to help optimise the shape of the hull and sponsons to minimise turbulence and drag. Fluent does a lot of work on aerodynamics with Formula 1 teams, and found a similar flow structure and vortex shedding during analysis of Quicksilver. CFD work was also carried out on the engine performance by the team’s specialist Chris Bell.

Craig Hornsby, principal CFD engineer at Fluent, largely focused on the aerodynamic performance, as most of the vessel will be in the air at full speed, with only four points touching the water. Early analysis of the model showed the exhaust exit was interacting strongly with the large wing or spoiler. ‘As this was supposed to be aerodynamically neutral, the design was altered,’ says Hornsby.

Judging hydrodynamic performance is more complex. ‘Though it can be analysed, it is quite difficult because the CFD analysis is time dependent, and capturing numerical details of the spray is very tricky,’ says Hornsby. ‘We are going to model multi-phase flows around each planing shoe of the active ride system. This means modelling air and water simultaneously and the impact of cavitation. The water speed record is more risky than land speed or air speed attempts as there are so many unknowns.’

Extensive physical tests on 1/8th-scale models were carried out in a moving-ground wind tunnel at the University of Southampton. Tests helped obtain a contour map showing the quality of air at the engine compressor face, so the intake shape could be optimised to provide smooth air to the engine for maximum power. Water-borne tests were conducted with a 1/8th-scale model in the towing tank facility at Qinetiq.

Macknight and his team are now satisfied with Quicksilver’s shape, and say the main focus is to keep the weight down to the target of 7,000lb. However, shapes that are optimised for very high speeds do not perform well at low speeds. ‘It’s a matter of compromise. You need a large surface area to get lift at low speed to get on top of the water quickly, but a small area to avoid flipping at high speed. Ideally the boat should be streamlined, but mustn’t take off at the peak of the run.’

Early last year the aircraft-quality tubular steel space-frame was built by PDS Engineering in Nelson, Lancs, and BOC Gases, and is being fitted out with mechanical and electrical systems. Engine installation will take place this winter, followed by fitting of the composite external panels. The plan is behind schedule due to cash constraints.

Macknight acquired two Rolls-Royce Spey Mk101 engines (one as a spare), along with an ex-Dera Buccaneer test aircraft at an MoD surplus auction for about £20,000. The aircraft is taxied around Bournemouth airport every few weeks to keep the engines in running order. The engines generate 11,000lb of thrust each, about 20,000hp.

The bodywork and sponsons will be formed from an integrated aluminium honeycomb sandwich core clad with carbon-fibre inner and outer skins, for greater strength and rigidity. The body’s modular design features a detachable nose cone, sponsons, cockpit section and tail surfaces.

Making the record attempt on Coniston is a challenge because it is almost too short for Quicksilver’s power (twice that of Bluebird). The lake is only five miles long, and according to the rules the UIM run must be made at record-breaking speed over one measured mile or kilometre, and repeated within 60 minutes. ‘I have three miles to accelerate and two miles to decelerate. It’s marginal, and we’re restricted to a time window by the Lake District National Park Authority between January and March in 2004.’

Though the fastest Macknight has been on water so far is 70mph, his plan has always been to attempt the record himself, and he emphasises that Richard Noble and other earlier contenders were not trained pilots. In preparation and training for the attmpt he is learning to fly, and plans to drive a 100mph single-seat jet-propelled hydroplane before his record attempt.

Will he succeed? ‘Going for the water speed record is not like learning to fly. I’ll learn by doing. I’m reasonably fit and prepared mentally to fulfil a childhood ambition. This is a dangerous activity, which has cost several lives. But we believe Quicksilver can use modern technology and rigorous scientific testing to make this a far safer endeavour, bringing the record back to Britain.’