Proteus-Bluebird Campbell-Norris 7

Country of ManufactureGreat Britain
Engine 
    ManufacturerBristol-Siddeley Proteus 705 gas turbine aircraft engine (modified to give drive shaft at each end)
    Compressor12 axial-flow stages, 1 centrifugal stage, 8 combustion chambers 2 two stage turbines
    Max. Power4,000bhp at 11,000-11,800 power turbine rpm and 11,800 compressor rpm, plus 1,000lb approx. exhaust thrust at standstill diminishing with speed
Transmission 
    Clutchnone
    Gearbox 
    Ratios 
    Axlesspiral bevel at front and rear
    Type of drivefinal drive 3.6 to 1
Chassis“Aeroweb” sandwich 2 skins 0.048in thick light alloy spaced 3/4in apart by resin bonded 1/4in mesh honeycomb of 0.002in thick light alloy
Suspensionindependent by ball-jointed transverse wishbones
Shock AbsorbersGirling oleo-pneumatic suspension struts with rubber rebound buffers
Steering GearBurman recirculating ball quick-thread mechanism as centre section of 3-piece track rod, operated by bevel gear and chains from steering wheel
BrakesGirling disc brakes, inboard mounted, with duplicated operation from compressed air reservoirs. Discs 16 3/8in external dia. and 10 3/8in internal dia. Air brakes to rear
WheelsDunlop split-rim disc wheels
TyresDunlop 7.8in section 52in external dia.
Dimensions 
    Wheelbase13ft 6in
    Track front5ft 6in
    Track rear5ft 6in
    Length30ft
    Weight72-80cwt
Fuel Tank Capacity25 gallons
Bodywork 
    ManufacturerMotor Panels Ltd.
    Materialaluminium

After Campbell’s record attempt on Lake Mead in 1955, Bluebird K7 was washed down and polished and put on display by the swimming pool at the Sahara hotel. He was entertained by Charles Russell – the Governor of Nevada and presented with a very large gold cup. Over dinner one evening, it was put to Campbell that he should go for the unique double of breaking the land and water speed record in one calendar year. Donald gave this some thought as they returned back to England on the Queen Mary.

He discussed the idea with the Norris Brothers in early 1956, and work began on designing a new car. It was to be powered by a Bristol Siddeley ‘Proteus’ aircraft engine, used in the Bristol Britannia airliner. Power was distributed to all four wheels by two David Brown single-split gearboxes with differentials, with no clutches or gears necessary. Air for the turbine was drawn in through the car’s nose and ducted round the driver, the cockpit was positioned forward of the front wheels, and its wheelbase was identical to that of John Cobb’s ‘Railton’. The car’s symmetry was spoiled by its huge wheels, developed by Dunlop. It was constructed by the efforts of around eighty British companies, and estimated to have cost around £1 million and another £1 million to mount the operation.

Bluebird CN7 arrived on the Bonneville Salt Flats in August 1960, with eighty or ninety personnel, several auxiliary vehicles and masses of spare parts, which left the American’s gasping. Campbell in return was shocked to see several American back yard specials.

There was Athol Graham’s ‘City Of Salt Lake’, Art Arfon’s ‘Green Monster’, Mickey Thompson’s ‘Challenger 1’ and Dr Nathan Ostich’s ‘Flying Caduceus’ the first pure-jet engined car, which was currently against the regulations at that time.

On August 1st 1960, Athol Graham’s car was travelling at well over 300mph , when it yawed off course, the tail flew off and it spiralled into the air before it landed upside down and rolled over several times. Graham had not worn a seat belt, and although the rollover bar withstood the impact, the firewall intruded into the cockpit and broke his spine. He was pronounced dead by the time he arrived at the nearest hospital 110 miles away.

Ostich’s car developed severe vibrations around the 300mph mark, and he withdrew back to Los Angeles for a rethink. Mickey Thompson got several runs in, including one at 354.33mph. Arfon’s appearance on the salt flats was rather brief. On one run he achieved 249.57mph before a wheel bearing seized on the return run. He realised his car was not in the same league as the others, and withdrew from the race. However, Arfons did succeed later in the 1960’s in a different ‘Green Monster’.

This left Campbell. He made several gentle runs and worked up his speeds gradually. On his fifth run he accelerated much harder from the start line to a speed around 360mph, when a cross wind blew the car off track. CN7 left the black marker line, and spun sideways. It rolled, leapt into the air, hit the ground and bounced six or seven times, before losing its two right wheels and shedding bits of metalwork. It eventually stopped, and when Leo arrived in the safety car, he found that the engine was till running, testament of the car’s strength and construction. He removed the cockpit canopy and Campbell was found to have suffered a fractured skull, a fractured eardrum and diverse cuts and bruises.

Campbell was hospitalised for several weeks whilst he recovered. On regaining consciousness, he asked how the car was and how soon it could be repaired. On hearing this, Sir Alfred Owen and other British organisations undertook to rebuilding her.

There are several theories to why the car crashed. Some people thought that Donald was being reckless and accelerated too fast, some blame the cross winds and others blame the oxygen supply he was breathing through his oxygen mask. This could have made him lose consciousness as some fighter pilots have experienced. To solve this problem, on future runs he was given a whiff of carbon dioxide before setting off.

Once he had recovered sufficiently, he thought carefully about the next choice of venue. Donald ruled out Bonneville as he felt the course was not long enough and the salt had deteriorated. British Petroleum, his major sponsor, sent out an expedition party to Australia to examine a vast dried lake bed called Lake Eyre, which is approximately 450 miles inland from Adelaide in Southern Australia.

The reports were encouraging, the salt was very hard and flat, but marred by many salt islands which would have to be ground down somehow. The chance of rain was felt to be rather slim, as none had fallen for years, but it was so remote that the nearest sheep and cattle station was thirty miles away at Muloorina and a road would need to be laid to transport supplies in.

The South Australian government were keen to allow Campbell to run CN7 on these salt flats, and agreed to build a 400 yard wide causeway to the lake itself, and they graded sixty five miles of road from the railhead at Marree to Muloorina. The looked less graceful and had the addition of a huge tailfin fitted for stability reasons.

Just as the team was preparing to transport CN7 to the salt flats in 1962, a report came through to Donald from British Petroleum representatives saying that heavy rain had fallen onto the lake, and the trip was postponed. The rain fell so heavy that it did not drain for months, and a whole year passed before Campbell and his entourage of men and equipment moved to the outback again in the Spring of 1963.

Heavy rain fell again, and flooded the course. The new course had also been ruined and boxes of equipment were thrown across the salt flats; the desert was useless for high speed runs.

Public opinion was highly critical, Bluebird had been around for too long and a record breaker is only successful for a limited number of failures. The press were scornful of failure and unaware of the conditions Campbell experienced. Sponsors were on the edge and highly critical. In America, a new contender, Craig Breedlove, had driven a pure jet car across the Bonneville Salt Flats and set an unofficial Land Speed Record of 407mph in 1963 in his three wheeled ‘The Spirit Of America’.

Campbell returned to Muloorina in April 1964 to try again. British Petroleum had withdrawn their support and finance and sponsors were highly critical of the way that Campbell was managing this project.

Corrosion had affected the metal panels and also affected the car’s electronics. On May 1st, the rain fell again laying four inches of water across the track. A new stretch of track was located, but it was not ideal being a few miles short. However, on May 5th tests recommenced.

Donald experienced vibrations in the car as he drove CN7 over 300mph. People were critical and thought that Campbell’s accident in 1960 had left permanent side effects. However, Ken Norris studied the footage and the car’s black box. He located the problem; he had found that wet salt was being sprayed onto the wheels and drying, affecting the wheels balance. On 28th May, CN7 achieved 352mph on 70 per cent power.

A further month passed and severe winds halted trials. Campbell did trial runs when conditions were less than perfect, and the team disbanded at the end of May whilst conditions on the lake improved.

In late June or early July 1964, the team returned for another attempt. Donald was aware that Craig Breedlove was preparing to run again at Bonneville, and was eager to prove CN7’s worth. Yet again the rain fell and the mood in the camp was sour, the team were restless and on edge, whilst they waited for ideal conditions. Nothing seemed simple for Donald Campbell, and on the 14th July, he achieved 320mph on a rather bumpy track. Things looked better on the 16th but winds were blowing and no runs were made that day.

On the Friday 17th July 1964, in less than ideal conditions Campbell achieved one run of 403.10mph. While the tyres were changed, Campbell was found staring at the open cockpit window. Afterwards, he said he saw his father’s reflection who told him ’Now you know what it felt like in 1935, but don’t worry old boy, it’ll be all right’. With this, Campbell returned on the same track, which now had grooves in it from his previous run, and amazingly achieved 403.10mph. He’d done it at last, Campbell had officially broken the wheel driven Land Speed Record. Campbell knew that given the right conditions, CN7 could achieve higher speeds.

In 1966, Donald agreed to do a demonstration run at Debdon in CN7. He allowed his co-driver have a go in case he was ill on the day. Peter Bolton drove her on a test run and crashed the car through a hedge at the end of the runway, struck a ditch and bounced across a main road before stopping near a field. It was repaired cosmetically overnight, and Donald drove it the next day at slow speeds. It if was to attempt aanother record, the estimate to repair the damage was £50.000 and Campbell was at an all time low.

In 1971, Craig Breedlove, who had already achieved 600mph on land, approached Tonia Bern-Campbell, Donald’s widow, with intentions of modifying CN7 and going for the wheel Land Speed Record. His plan was to modify the car by moving the cockpit into the car’s tail to improve the aerodynamics; this was referred as ‘Bluebird America’. Interest and sponsors were not forthcoming and the project remained stillborn. Richard Noble even mentioned running the car when things looked bleak during his Thrust 2 project, but his thoughts were never taken seriously.

CN7 can now be seen along with Henry Segrave’s 2000hp Sunbeam, the Golden Arrow and Malcolm Campbell’s V12 Sunbeam Bluebird, at Beaulieau Motor Museum.

John Bullivant, 2002

Acknowledgements:

"100 Years Of The World’s Land Speed Record 1898 – 1998: Part Two: The Second Half Century" by Ferdinand C W Kasmann.

"The Land Speed Record- From 39.24 to 600 +mph" by Cyril Posthumus and David Tremayne.

"The Record Breakers – Sir Malcolm and Donald Campbell Land and Water Speed Kings of the 20th Century" by Leo Villa and Tony Gray.