Bluebird K7
Bluebird K7 was a turbo jet-engined hydroplane with which the United Kingdom's Donald Campbell set seven world water speed records during the 1950s and 1960s. Campbell lost his life in K7 on January 4, 1967 whilst making a bid to raise the speed record to over 300 miles per hour (480 km/h) on Coniston Water.
Contents |
[edit] Design
Donald Campbell began his record-breaking career in 1949. Hitherto, he had been using his father Sir Malcolm Campbell's propellor-driven hydroplane Bluebird K4 for his attempts, but in 1951 it was destroyed by structural failure, when its gearbox sheared its mountings, and punched through the floor of the hull.
Following rival racer John Cobb's death in Crusader in 1952, Campbell began development of his own all metal jet-powered Bluebird K7 to challenge the record held by the American hydroplane Slo-Mo-Shun IV.[1] Designed by Ken and Lew Norris, the K7 was an aluminium, three-point hydroplane with a Metropolitan-Vickers Beryl axial-flow turbojet engine, producing 3500 pound-force (16 kN) of thrust. Like Slo-Mo-Shun, but unlike Cobb's tricycle Crusader, the three points were arranged in "pickle-fork" layout, prompting Bluebird's early comparison to a blue lobster. It was very advanced, and remained the only successful jet-boat until well into the 1960s.
The name "K7" was derived from its Lloyd's unlimited rating registration. It was carried on a prominent circular badge on its sponsons, underneath an infinity symbol.
[edit] Bluebird K7 Records
Campbell set seven world water speed records in K7 between 1955 and 1964. The first of these occurred at Ullswater on 23 July 1955, where he set a record of 202.15 mph (324 km/h). Campbell achieved a steady series of subsequent speed-record increases with the boat during the rest of the decade, beginning with a mark of 216 mph (348 km/h) in 1955 on Lake Mead. Subsequently, four new marks were registered on Coniston Water, where Campbell and Bluebird became an annual fixture in the later half of the fifties, enjoying significant sponsorship from the Mobil oil company and then subsequently BP. There was also an unsuccessful attempt in 1957 at Canandaigua in New York state in the summer of 1957, which failed due to lack of suitable water conditions. Bluebird K7 became a popular attraction, and well as her annual Coniston appearances, K7 was displayed extensively in the UK, USA, Canada and Europe, and then subsequently in Australia during Campbell's prolonged attempt on the land speed record (LSR) in 1963 - 64.
In order to extract more speed, and endow the boat with greater stability, in both pitch and yaw, K7 was subtly modified in the second half of the 1950s with the installation of smoother streamlining, a blown cockpit canopy and, from 1958 onwards, a small wedge shaped tail fin, modified sponson fairings, that reduced aerodynamic lift, and a fixed hydrodynamic fin, fixed to the transom to aid hydrodynamic stability, and exert a marginal downforce on the nose. Thus she reached 225 mph (362 km/h) in 1956, where an unprecedented peak speed of 286.78 mph (461.53 km/h) was achieved on one run, 239 mph (385 km/h) in 1957, 248 mph (399 km/h) in 1958 and 260 mph (420 km/h) in 1959.
Campbell then turned to the LSR, and after surviving a high speed crash in his Bluebird CN7 turbine powered car, he spent a frustrating two years in the Australian desert, battling adverse conditions. Finally, after Campbell exceeded the LSR on Lake Eyre in 1964, at 403.10 mph (648.73 km/h) in Bluebird CN7, Campbell snared his seventh water speed record on 31 December 1964 at Dumbleyung Lake, Western Australia, when he reached 276.33 mph (444.71 km/h), with two runs at 283.3 mph (455.9 km/h) and 269.3 mph (433.4 km/h) completed with only hours to spare on New Years Eve 1964.
This made Campbell and K7 the world's most prolific breakers of the Water Speed Record. Campbell became the only person to break both the Land Speed Record and the Water Speed Record in the same year.
[edit] The Final Water Speed Record attempt and Donald Campbell's death
In June 1966, Campbell decided to once more try for a water speed record with K7: his target, 300 mph (480 km/h).
K7 was fitted with a lighter and more powerful Bristol Siddeley Orpheus engine, taken from a Folland Gnat jet aircraft, and lent to the project by the MOD, which developed 4,500 pound-force (20 kN) of thrust. The new K7 had a vertical stabiliser (also from a Gnat Campbell had purchased ) and a new hydraulic water brake designed to slow the boat down on the five-mile Coniston course.The boat returned to Coniston for trials in November 1966. These did not go well; the weather was appalling and K7 destroyed her engine when the air intakes collapsed under the demands of the more powerful engine, and debris was drawn into the compressor blades. The engine was replaced, Campbell using the unit from the scrapped, crash-damaged Gnat aircraft that he had purchased at the project's start.[2] The original engine remained outside the team's lakeside workshop for the rest of the project, shrouded in a tarpaulin.
By the end of November, after further modifications to alter K7's weight distribution, some high-speed runs were made, but these were timed at well below the existing record. Problems with the fuel system meant that the engine could not develop maximum power. By the middle of December, Campbell had made a number of timed attempts, but the highest speed achieved was 264 mph, and therefore still shy of the existing record. Eventually, further modifications to K7's fuel system (involving the fitting of a booster pump) fixed the fuel-starvation problem. It was now the end of December and Campbell was all set to proceed, pending only the arrival of suitable weather conditions.
On 4 January 1967, Campbell mounted his record attempt. He was killed when K7 flipped over and broke up at a speed in excess of 300 mph (480 km/h).[3] Bluebird had completed a perfect north-south run at an average of 297.6 mph (478.9 km/h), and Campbell used a new water brake to slow K7 from her peak speed of 315 mph (507 km/h). Instead of refuelling and waiting for the wash of this run to subside, as had been pre-arranged, Campbell decided to make the return run immediately. The second run was even faster; as K7 passed the start of the measured kilometre, she was travelling at over 320 mph (510 km/h). However her stability had begun to break down as she travelled at speed she had never achieved before, and the front of the boat started to bounce out of the water on the starboard side. 150 yards from the end of the measured mile, K7 lifted from the surface and after about 1.5 seconds, gradually lifted from the water at an ever increasing angle, before she took off at a 90-degree to the water surface. She somersaulted and plunged back into the lake, nose first. The boat then cartwheeled across the water before coming to rest. The impact broke K7 forward of the air intakes (where Donald was sitting) and the main hull sank shortly afterwards. Campbell had been killed instantly. Mr Whoppit, Campbell's teddy bear mascot, was found among the floating debris and the pilot's helmet was recovered. Royal Navy divers made efforts to find and recover the body but, although the wreck of K7 was found, they called off the search, after two weeks, without locating his body.
Campbell's last words on his final run were, via radio intercom:
| “ | Pitching a bit down here...Probably from my own wash...Straightening up now on track...Rather closer to Peel Island...Tramping like mad...and er... Full power...Tramping like hell here... I can't see much... and the water's very bad indeed...I can't get over the top... I'm getting a lot of bloody row in here... I can't see anything... I've got the bows out... I'm going!....ugh"[4] | ” |
The cause of the crash has been variously attributed to Campbell not waiting to refuel after doing a first run of 297.6 mph (478.9 km/h) and hence the boat being lighter; the wash caused by his first run and made much worse by the use of the water brake, (These factors have since been found to be not particularly important. The water brake was used well to the south of the measured distance, and only from approx. 200 mph (320 km/h) The area in the centre of the course, where Bluebird was travelling at peak speed on her return run was flat calm, and not disturbed by the wash from the first run, which had not had time to be reflected back on the course. The fuel tank was in approx. the same position as K7's centre of gravity, and therefore had little impact on the boats weight distribution), and potentially a cut-out of the jet engine caused by fuel starvation. (The configuration of K7 at high speed meant that the thrust of the jet engine provided a downward pressure at the bows of the boat. K7 was operating at her absolute limit in terms of a nose up pitching angle of 6'. A sudden loss of power caused by an interruption to fuel flow would mean that this downthrust was lost and K7's bows would have risen above the 6' safe limit) Some evidence for this last possibility may be seen in film recordings of the crash - as the nose of the boat climbs and the jet exhaust points at the water surface no disturbance or spray can be seen at all. A complete analysis of the causes of the accident will be published in 'Donald Campbell Bluebird and The Final Record Attempt' towards the end of 2011.
[edit] Recovery of Bluebird K7
The wreckage of Campbell's craft was recovered by the Bluebird Project between October 2000, when the first sections were raised, and May 2001, when Campbell's body was recovered. The largest section, representing approximately two-thirds of the main hull, had been salvaged on 8 March 2001.
A diving team led by Bill Smith was responsible for finding the wreckage.
[edit] Controversy over the recovery
The exact date of the retrieval of Campbell's body from the lake was 28 May 2001. He was interred in Coniston cemetery on 12 September that year.
Campbell's sister Jean Wales had been against the recovery of the boat and her brother's body out of respect for his stated wish that, in the event of something going wrong: "Skipper and boat stay together." This quotation is usually said to have been uttered by Campbell when, in the final week of 1964, he was waiting for good weather to attempt a record run, but a bid seemed so unlikely at that point, his colleagues were pressing him to leave. He refused, and broke the record on the last day of 1964. Jean Wales did not attend his burial or visit his grave although she did remain in daily contact with the salvage crew as the boat's wreckage was being brought ashore.
[edit] Forensic examination of the wreckage and the causes of the accident
Because the boat's water brake was found to be extended when the wreck was recovered, it was generally assumed that Campbell had activated it to slow down before the boat had left the water on his final run. On dismantling the boat, however, a hydraulic accumulator from the donor Gnat aircraft was discovered to be still connected to the system, meaning that stored hydraulic pressure may well have deployed the brake after the accident.
The boat still contained fuel in the engine fuel lines and a quantity was collected and analysed using gas-chromatography as part of the official investigation of the accident commissioned by Barrow Coroner. However, insufficient was present to completely discount the fuel starvation theory. The engine could have cut-out as a result of intermittent fuel starvation caused by the untried fuel system or failure of the electrical supply to the low-pressure fuel-boost pumps. Full details of the boat's strip-down, and the conclusions drawn from it by the investigators, are lodged within the public domain in the diary pages of the Bluebird Project website.
[edit] Restoration and future running
As of 2008[update], K7 is being fully restored, to a very high standard of working condition in North Shields, Tyne and Wear, using a very high proportion of her original fabric, but with a new engine of the same type albeit incorporating many original components.
As of May 2009 permission has been given for a one off set of proving trials of Bluebird on Coniston Water, where she will be tested to a safe speed for demonstration purposes only. Whether and when she is finally tested will be up to the British government. The restoration of Bluebird is heading towards completion in 2012/13. K7 will find her permanent resting place at the Ruskin Museum in Coniston, where she will be on display to the general public in her own wing, which was completed in 2009.
[edit] References
- ^ Tremayne, David (2005). Donald Campbell: The Man Behind the Mask. Bantam Books. ISBN 0553815113.
- ^ Knowles, Arthur (2001). The Bluebird Years. Sigma Leisure. ISBN 978-1-85058-766-8.
- ^ GRO Register of Deaths: MAR 1967 10F 692 ULVERSTON - Donald M. Campbell, aged 45
- ^ "Last words from Bluebird". BBC News. 2002-12-10. http://news.bbc.co.uk/1/hi/england/2560957.stm. Retrieved 2009-12-31.
[edit] External links
- Bluebirdproject.com - the restoration project for K7
- Donald Campbell, Bluebird and the Final Record Attempt
- DONALD-CAMPBELL-BLUEBIRD-AND-THE-FINAL-RECORD-ATTEMPT Facebook page
 External images |
|
|---|---|
 |
The wreckage of the tailfin of K7 |
