Turn back the clock

Why analogue dials will be vital

When Andy Green eventually attempts to take Bloodhound to a four-figure speed in 2020, he is expected to experience a force of 2.5g as Bloodhound travels from standstill to 1000mph in a difficult-to-comprehend 55 seconds. Slowing it down, meanwhile, will result in deceleration forces of up to 3g as the combination of air brakes, parachutes and finally disc brakes are deployed to draw Bloodhound to a safe halt.

A high-tech digital screen and a mass of electrical switches will enable Green to operate the car’s myriad mechanisms – but the two most important instruments at his disposal will be instantly recognisable to anyone, as they take the form of a pair of traditional-looking analogue dials mounted on the dashboard pods to either side of Bloodhound’s multi-function steering wheel.

Developed and supplied by Rolex, the highly accurate units comprise a speedometer featuring a scale of zero to 11 (and marked with the all-important legend ‘X100’) together with a matching chronograph and time clock.

Despite the ability of digital technology to slice a second in to fractions of mind-bogglingly small proportions, it is thought that the human brain is quicker to process information provided by a traditional, analogue dial – so, while the central electronic screens will inevitably be more accurate, the Rolex instruments are there to provide at-a-glance data and serve as a fail-safe back-up in the event of a significant systems failure.

Green will use them during two critical phases of the record bid: firstly, to time the all-important braking sequences required to slow Bloodhound down before it reaches the end of the 19-kilometre track; and, secondly, to monitor the time during the turnaround between the two runs that must be made in order for the land speed record attempt to be recognised officially.