The world unlimited Water Speed Record is the officially recognised fastest speed achieved by a water-borne vehicle, irrespective of propulsion method. The current unlimited record is 511.11 km/h (317.59 mph), achieved by Australian Ken Warby in the Spirit of Australia in 1978.
The record is one of the sporting world's most hazardous competitions. Of the thirteen people who have attempted the record since June 1930 seven have died. There has been two official attempts to beat Ken Warby's 1978 record, and both resulted in the death of the pilot; Lee Taylor (1980) and Craig Arfons (1989). Despite this, there are several teams currently working to make further attempts.
The record is ratified by the Union Internationale Motonautique (UIM).
Until 1911 the world water speed records were held by steam-powered, propeller-driven vehicles.
In 1911 a 12 m (40 ft) stepped planing hull, Dixie IV, designed by Clinton Crane, became the first gasoline powered vessel to break the water speed record.
Beginning in 1908 Alexander Graham Bell and engineer Frederick W. "Casey" Baldwin began experimenting with powered watercraft. In 1919, with Baldwin piloting their HD-4 hydrofoil, a new world water speed record of 114.0 km/h (70.86 mph) was set on Bras d'Or Lake at Baddeck, Nova Scotia.
In 1920, Garfield Wood set a new water speed record of 71.43 mph (114.96 km/h) on the Detroit River, using a new boat called Miss America. In the following twelve years, Wood built nine more Miss Americas and broke the record five times. Increased public interest generated by the speeds achieved by Wood and others led to an official speed record being ratified in 1928. The first person to try a record attempt was Wood's brother, George. On 4 September 1928, he drove Miss America VII to 149.40 km/h (92.8 mph) on the Detroit River. The next year, Gar Wood took the same boat up a waterway Indian Creek, Miami Beach and reached 149.86 km/h (93.12 mph).
Like the land speed record, the water record was destined to become a scrap for national honour between the United Kingdom and the United States. American success in setting records spurred Castrol Oil chairman Lord Wakefield to sponsor a project to bring the water record to Britain. Famed land speed racer and racing driver Sir Henry Segrave was hired to pilot a new boat, Miss England. Although the boat was not capable of beating Wood's Miss America, the British team did gain experience, which was put into an improved boat. Miss England II was powered by two Rolls-Royce aircraft engines and seemed capable of beating Wood's record.
On 13 June 1930 Segrave piloted Miss England II to a new record of 158.94 km/h (98.8 mph) average speed during two runs on Windermere, in Britain's Lake District. Having set the record, Segrave set off on a third run to try to improve the record further. Unfortunately during the run, the boat flipped, with both Segrave and his co-driver receiving fatal injuries.
Following Segrave's death, Miss England II was salvaged and repaired. Kaye Don was chosen as the new driver for 1931. However, during this time, Gar Wood recaptured the record for the U.S. at 164.41 km/h (102.16 mph). A month later on Lake Garda, Don got the record back with 177.387 km/h (110.2 mph). In February 1932, Wood responded, nudging the mark to 179.779 km/h (111.709 mph).
In response to the continued American challenge, the British team built a new boat, Miss England III. The design was an evolution of the predecessor, with a squared-off stern and twin propellers being the main improvements. Don took the new boat to Loch Lomond, Scotland, on 18 July 1932, improved the record first to 188.985 km/h (117.430 mph), then to 192.816 km/h (119.810 mph) on a second run.[clarification needed]
Determined to have the last word over his great rival, Gar Wood built another new Miss America. Miss America X was 12 metres (39 ft) long, powered by four supercharged Packard aeroplane engines. On 20 September 1932 Wood broke the 200 km/h (120 mph) barrier, driving his new boat to 200.943 km/h (124.860 mph). It would prove the end of an era. Don declined to attempt any further records. Wood also opted to scale down his involvement in racing and returned to running his businesses. Somewhat ironically, both record-breakers lived into their 90s. Wood died in 1971, Don in 1985.
Wood's last record would be one of the final records for a conventional, single-keel boat. In June 1937 Malcolm Campbell, the world-famous land speed record breaker, drove Blue Bird K3 to a new record of 203.31 km/h (126.33 mph) at Lake Maggiore. Compared to the massive Miss America X, K3 was a much more compact craft. It was 5 metres shorter and had one engine to X's four.
Despite his success, Campbell was unsatisfied by the relatively small increase in speed. He commissioned a new Blue Bird to be built. Blue Bird K4 was a ‘three pointer’ hydroplane. Unlike conventional powerboats, which have a single keel, with an indent, or ‘step’, cut from the bottom to reduce drag, a hydroplane has a concave base with two sponsons fitted to the front, and a third point at the rear of the hull. When the boat increases in speed, most of the hull lifts out of the water and runs on the three contact points. The positive effect is a reduction in drag; the downside is that the three-pointer is much less stable than the single keel boat. If the hydroplane's angle of attack is upset at speed, the craft can somersault into the air, or nose-dive into the water.
Campbell's new boat was a success. In 1939, on the eve of the Second World War, he took it to Coniston Water and increased his record by 18 km/h (11 mph), to 228.11 km/h (141.74 mph).
The return of peace in 1945 brought with it a new form of power for the record breaker – the jet engine. Campbell immediately renovated Blue Bird K4 with a De Havilland Goblin jet engine. The result was a curious-looking craft, whose shoe-like profile led to it being nicknamed ‘The Coniston Slipper’. The experiment with jet-power was not a success and Campbell retired from record-attempts. He died in 1948.
On 26 June 1950, Slo-Mo-Shun IV improved on Campbell's record by 29 km/h (18 mph). Powered by an Allison V-1710 aircraft engine, the boat was built by Seattle Chrysler dealer Stanley Sayres and was able to run 260 km/h (160 mph) because her hull was designed to lift the top of the propeller out of water when running at high speed. This phenomenon, called ‘prop riding’, further reduced drag.
In 1952, Sayres drove Slo-Mo-Shun to 287.25 km/h (178.49 mph), a 29 km/h (18 mph) increase on his previous record.
The renewed American success persuaded Malcolm Campbell's son, Donald, who had already driven Blue Bird K4 to within sight of his father's record, to make a further push for the record. However, Blue Bird K4 was by now 12 years old, with a 20-year-old engine, and Campbell struggled to reach the speeds of the Seattle-built boat. In late 1951, it was written off after suffering a structural failure at 270 km/h (170 mph) on Coniston Water.
At this time, yet another land speed driver entered the fray. Englishman John Cobb, was hoping to reach 320 km/h (200 mph) in his jet-powered Crusader. A radical design, the Crusader reversed the ‘three-pointer’ design, placing the sponsons at the rear of the hull. On 29 September 1952 Cobb tried to beat the world record on Loch Ness but, while travelling at an estimated 338 km/h (210 mph), Crusader's front plane collapsed and the craft instantly disintegrated. Cobb was retrieved from the water but had already died of shock.
Two years later, on 8 October 1954, another man would die trying for the record. Italian textile magnates Mario Verga and Francesco Vitetta, responding to a prize offer of 5 million lire from the Italian Motorboat Federation to any Italian who broke the world record, built a sleek piston-engined hydroplane to claim the record. Named Laura III, after Verga's daughter, the boat was fast but unstable. Travelling across Lake Iseo, in Northern Italy, at close to 306 km/h (190 mph), Verga lost control of Laura III, and was thrown out into the water when the boat somersaulted. Like Cobb, he died of shock.
Following Cobb's death, Donald Campbell started working on a new Bluebird, K7, a jet-powered hydroplane. Learning the many lessons from Cobb's ill-starred Crusader, K7 was designed as a classic 3 pointer with sponsons forward alongside the cockpit. She was designed by Ken and Lewis Norris in 1953-54 and was completed in early 1955. She was powered by a Metropolitan-Vickers Beryl turbojet of 16 kN (3,500 lbf) thrust. K7 was of all-metal construction and proved to have extremely high rigidity.
Campbell and K7 set a new record of 325.60 km/h (202.32 mph) on Ullswater in July 1955. Campbell and K7 went on to break the record a further six times over the next nine years in the US and England (Coniston Water), finally increasing it to 444.71 km/h (276.33 mph) at Lake Dumbleyung in Western Australia in 1964. Campbell thus became the most prolific water speed record breaker of all time.
At the time Campbell set the absolute record, the piston-powered propeller-driven record was held by the George Simons' Miss U.S. I  at 322.54 km/h (200.42 mph). This record was set at Guntersville, Alabama in 1962 by Roy Duby and stood for 38 years.
Donald Campbell's Bluebird K7 had been re-engined with a Bristol Siddeley Orpheus jet rated at 4,500 lbf (20 kN) of thrust. On 4 January 1967 he tried again. His first run averaged 475.2 km/h (295.3 mph) and a new record seemed in sight. Campbell applied K7's water brake to slow the craft down from her peak speed of 507 km/h (315 mph) clear of the measured kilometre to a speed around 350 km/h (220 mph). Rather than waiting for the lake to settle again before starting the mandatory return leg, Campbell immediately turned around at the end of the lake and began his return run. At around 512 km/h (318 mph), just as she entered the measured kilometre, Bluebird began to lose stability and 400 m before the end of the kilometre, Bluebird′s nose lifted beyond its critical pitch angle and she started to rise out of the water at a 45-degree angle. The boat took off, somersaulted and then plunged nose-first into the lake, breaking up as she cartwheeled across the surface. Campbell was killed instantly. Prolonged searches over the next two weeks located the wreck, but it was not until May 2001 that Campbell's body was finally located and recovered. Campbell was buried in the churchyard at Coniston on 12 September 2001. The 1988 television drama Across the Lake relates the attempt.
Lee Taylor, a Californian boat racer, in Hustler during a test run on Lake Havasu on 14 April 1964, was unable to shut down the jet and crashed into the lakeside at over 161 km/h (100 mph). Hustler was wrecked and Taylor was severely injured. He spent the following years recuperating, and rebuilding his boat. On 30 June 1967, on Lake Guntersville, Taylor and Hustler tried for the record, but the wake of some spectators' boats disturbed the water, forcing Taylor to slow down his second run, and he came up 3.2 km/h (2 mph) short. He tried again later the same day and succeeded in setting a new record of 459 km/h (285 mph).
Until 20 November 1977 every official water speed record had been set by an American, Canadian, Irishman, or Briton. That day Ken Warby became the first Australian holder when he piloted his Spirit of Australia to 464.46 km/h (288.6 mph; 250.8 kn) to beat Lee Taylor's record. Warby, who had built the craft in his back yard, used the publicity to find sponsorship to pay for improvements to the Spirit. On 8 October 1978 Warby travelled to Blowering Dam, Australia, and broke both the 300 mph (483 km/h; 261 kn) and 500.0 km/h (311 mph; 270 kn) barriers with an average speed of 511.11 km/h (317.59 mph; 275.98 kn). As he exited the course his peak speed as measured on a radar gun was approximately 555 km/h (345 mph; 300 kn).
Warby's record still stands. There have only been two official attempts to break it, both resulting in the death of the driver.
Lee Taylor tried to get the record back in 1980. Inspired by the land speed record cars Blue Flame and Budweiser Rocket, he built a rocket-powered boat, Discovery II. The 40-foot (12 m) long craft was a reverse three-point design, similar to John Cobb's Crusader, but of much greater length.
Originally Taylor tested the boat on Walker Lake in Nevada but his backers demanded a more accessible location, so he switched to Lake Tahoe. An attempt was set for 13 November 1980, but when conditions on the lake proved unfavourable, he decided against trying for the record. Not wanting to disappoint the assembled spectators and media, he decided to do a test run instead. At 432 km/h (270 mph) Discovery II started to become unstable. It has been speculated[by whom?] that it may have hit a swell.. Its unstable lateral oscillations caused the left sponson to collapse, sending the boat plunging into the water. The cockpit section with Taylor's body was recovered three days later. The cockpit had not floated as intended and Taylor drowned as a result.
On 9 July 1989 Craig Arfons, son of Walt Arfons, builder of the world's first jet car, and nephew of record breaker Art Arfons, tried for the record in his all-composite fiberglass and Kevlar Rain X Challenger. At 7:07 am, less than 15 seconds into his run, the hydroplane somersaulted at more than 350 mph (560 km/h). The cockpit remained intact underwater with Arfons remaining inside upside down. Two divers from a rescue team reached the wreckage and extracted him within three minutes of the initial incident. While he still had a pulse after cardiopulmonary resuscitation was administered, he did not respond to the medical personnel. He was taken to the Highlands Regional Medical Center but was pronounced dead at 8:30 am, 1 hour and 23 minutes after the initial incident.
Despite the high fatality rate, the record is still coveted by boat enthusiasts and racers. Ongoing projects aimed at breaking the record include the following:
The British Quicksilver project is managed by Nigel Macknight. The design was initially based on concepts for a rear-sponsoned configuration by Ken Norris, who had worked with the Campbells on their 'Bluebird' designs. The design is of modular construction with the main body consisting of a front section with a steel spaceframe incorporating the engine, a Rolls-Royce Spey Mk.101, and the rear section a monocoque extending to the tail. The front sponsons are also modules, one of which contains the driver.
Ken Warby is working with his son David on a new boat, powered by a jet engine taken from a Fiat G.91, to break the record. The team currently conducting a series of trials had, as of 31 August 2019, increased the speed to 407 km/h. Earlier in 2003, Ken Warby had built another boat, Aussie Spirit for a record attempt.
The K777 Team is a combination of engineers, boat racers, boat builders, gas turbine specialists and Members of Windermere Boat Racing Club. They built a controversial visual copy of Donald Campbell's Bluebird K7, though during its sole public appearance on Coniston Water in 2011 it failed to plane, partially sank, and ultimately collapsed its air intake trunking. A test on Loch Ken, in south-west Scotland, in October 2014 was also unsuccessful; although the boat did not sink, it was again unable to plane.
Daniel Dehaemers was the Belgian challenger for the absolute water speed record. The SP600 is of full carbon composite construction and is powered by a Rolls-Royce Adour 104 turbojet engine. The boat was planned to be tested during 2016. However, after finishing building the boat he died of cancer in 2018 before he managed to trial the craft. 
A British team, with a serving British military pilot at the helm, are working together to build and run Longbow, a jet hydroplane, on lakes and lochs within the UK, for a British attempt at the water speed record.
|317.596 mph (511.121 km/h)||Spirit of Australia||Ken Warby||Blowering Reservoir||8 October 1978|
|288.60 mph (464.46 km/h)||Spirit of Australia||Ken Warby||Blowering Reservoir||20 November 1977|
|285.22 mph (459.02 km/h)||Hustler||Lee Taylor||Lake Guntersville||30 June 1967|
|276.33 mph (444.71 km/h)||Bluebird K7||Donald Campbell||Lake Dumbleyung||31 December 1964|
|260.35 mph (418.99 km/h)||Bluebird K7||Donald Campbell||Coniston Water||14 May 1959|
|248.62 mph (400.12 km/h)||Bluebird K7||Donald Campbell||Coniston Water||10 November 1958|
|239.07 mph (384.75 km/h)||Bluebird K7||Donald Campbell||Coniston Water||7 November 1957|
|225.63 mph (363.12 km/h)||Bluebird K7||Donald Campbell||Coniston Water||19 September 1956|
|216.20 mph (347.94 km/h)||Bluebird K7||Donald Campbell||Lake Mead||16 November 1955|
|202.32 mph (325.60 km/h)||Bluebird K7||Donald Campbell||Ullswater||23 July 1955|
|178.497 mph (287.263 km/h)||Slo-Mo-Shun IV||Stanley Sayres, Elmer Leninschmidt||Lake Washington||7 July 1952|
|160.323 mph (258.015 km/h)||Slo-Mo-Shun IV||Stanley Sayres, Ted O. Jones||Lake Washington||26 June 1950|
|141.74 mph (228.11 km/h)||Blue Bird K4||Malcolm Campbell||Coniston Water||19 August 1939|
|130.91 mph (210.68 km/h)||Blue Bird K3||Malcolm Campbell||Hallwilersee||17 September 1938|
|129.50 mph (208.41 km/h)||Blue Bird K3||Malcolm Campbell||Lake Maggiore||2 September 1937|
|126.32 mph (203.29 km/h)||Blue Bird K3||Malcolm Campbell||Lake Maggiore||1 September 1937|
|124.86 mph (200.94 km/h)||Miss America X||Gar Wood||St. Clair River||20 September 1932|
|119.81 mph (192.82 km/h)||Miss England III||Kaye Don||Loch Lomond||18 July 1932|
|117 mph (188 km/h)||Miss England III||Kaye Don||Loch Lomond||18 July 1932|
|111.712 mph (179.783 km/h)||Miss America IX||Gar Wood||Indian Creek||5 February 1932|
|110.223 mph (177.387 km/h)||Miss England II||Kaye Don||Lake Garda||31 July 1931|
|103.49 mph (166.55 km/h)||Miss England II||Kaye Don||Paraná River||15 April 1931|
|102.256 mph (164.565 km/h)||Miss America IX||Gar Wood||Indian Creek||20 March 1931|
|98.760 mph (158.939 km/h)||Miss England II||Henry Segrave||Windermere||13 June 1930|
|93.123 mph (149.867 km/h)||Miss America VII||Gar Wood||Indian Creek||23 March 1929|
|92.838 mph (149.408 km/h)||Miss America VII||George Wood||Detroit River||4 September 1928|
|87.392 mph (140.644 km/h)||Farman Hydroglider||Jules Fisher||River Seine||10 November 1924|
|80.567 mph (129.660 km/h)||Miss America II||Gar Wood||Detroit River||6 September 1921|
|71.43 mph (114.96 km/h)||Miss America||Gar Wood||Detroit River||15 September 1920|
|70.86 mph (114.04 km/h)||HD-4||Casey Baldwin||Bras d'Or Lake||19 September 1919|
|57 mph (92 km/h)||The Maple Leaf III||Sir Edward Mackay Edgar||The Solent||March 1911|
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