1964: Proteus Bluebird CN7 driven by Donald Campbell

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Proteus Bluebird CN7

United Kingdom
Bristol Proteus 755
Bore x Stroke:
139.7 x 130.2 mm
47,872 cc
4250 bhp @ 11000 rpm
4 Tons (approx)
Top Speed:

403.10 mph

The Proteus Bluebird was unique in many ways, not least in being the first car designed for a world land speed record attempt to use a gas turbine engine.

The unit chosen by the Bluebird’s designers (the Norris Brothers) was a Bristol Siddeley Proteus 755, known to engineers at the time as a free turbine, but these days referred to as a "turbo-prop".

The Proteus drove all four wheels of "Bluebird", and at full throttle delivered 4,250 horse power.

There was no clutch and a fixed gear ratio, providing two-pedal control. Like all turbines, the Proteus turned over much faster than a piston engine, delivering maximum power at 11,000 rpm.

The Bluebird was 30 feet long, 8 feet wide, and 4 feet 9 inches high without its removable fin (with the fin in place this stretched to 7 ft 8” high). It weighed a relatively modest  9,600 lb when ready to run, and has a front track of 5 feet 6 3/4 inches and a rear track of 5 feet 6 inches.

Naturally enough the Bluebird used aviation turbine kerosene, and it was fortunate that BP was helping sponsor the car, given it consumed fuel at the rate of about one-and-a-half miles per gallon at full speed.

On Donald Campbell's record attempt at Bonneville Salt Flats, Utah, in 1960, the Bluebird accelerated from a standstill to nearly 400 mph over one-and-a-half miles in 24 seconds.

Most surprising was that less than 80 per cent of full power was then being used. This Bluebird was then severely damaged after a huge crash later in the same month.

The car was completely rebuilt, thanks to the generosity of Sir Alfred Owen, with the only noticeable changes being a different shaped cockpit cover and the addition of a tail fin for extra stability.

The first trials of the rebuilt Bluebird CN7 took place at Lake Eyre in Australia in May 1963, with the world land speed record being set at 403.10 mph at Lake Eyre on 17th July, 1964 after months of torrential rain and flooding.

The Proteus engine used in "Bluebird" was of the same type used to propel the fastest warships in the world, the Royal Navy's "Brave" class fast patrol boats. Like all gas turbines of this type it delivered high power for its bulk and weight, being 8 feet 01 inches long and 40 inches in diameter, and weighing about 3000 lb.

It required no cooling system, and no clutch because it used the equivalent of a fluid torque converter. The output shaft was coupled permanently and directly to bevel gears in both the front and rear axles. The engine turbine provided no engine braking on the over-run at low speeds, but at 400 mph approximately 500 hp was available for braking when the throttle was closed.

There was, however, two rather more ingenious braking systems fitted to the Bluebird. Power-air flaps opened out from the rear of the vehicle, and power operated Girling disc brakes were fitted to all four wheels; remarkably for the time these discs were able to run at a maximum temperature of 2,200 degrees F.-almost white hot.

The Bluebird's complex cockpit instrumentation was reflected onto the windscreen and focused onto the horizon ahead so that Campbell could see the course and his instrument readings simultaneously.

Also See:

Land Speed Record Drivers
Herbert Austin LSR Attempt
History Of The Land Speed Record
Unique Cars and Parts USA - The Ultimate Classic Car Resource