One of the big challenges for BLOODHOUND is taking a component that exists in day-to-day life and making sure it is suitable and capable of being used in the world of BLOODHOUND – that is a dusty/sandy desert, hot and cold days and at speeds up to 1050 mph at ground level.
Any one of these factors is not exceptional but the combination is what makes the environment of BLOODHOUND unique.
One such component we are taking the time to test are the Brake rotors. The carbon-carbon rotor we are using is very similar to those used on aircraft all over the world – so what is the problem – why are we being cautious?
The brakes used on aircraft are made up of a number of rotors and a number of stators – the stators are the fixed part and the rotors rotate with the wheel. They are designed to cope with the braking of heavy airliners and so are capable of absorbing huge amounts of energy.
The rotors are rated to brake from speeds of around 250mph. So they seem like an obvious solution to the wheel brakes of BLOODHOUND.
Our car is light, a mere 6.5 tonnes compared to an airliner, we only want to use the wheel brakes for the final slowing of the car at low speeds of around 200mph – so again, no problem. The issue lies with the fact that the brake stacks on an aircraft are static at high speed – obviously, the wheels are in the air and so aren’t spinning. They only start moving once the plane hits the runway – so the rotors in the brake stack only experience relatively low speeds.
With BLOODHOUND, our rotors will need to be able to withstand high speeds – up to 10,000 rpm. This is something these brakes were never designed to do, and so we are keen to understand just how they will react.
Over the next couple of months we are machining four rotors – two sourced from the UK, and two from South Korea, to our final design. We then plan to carry out a number of spin tests at different speeds to verify their stability at high rpm. We will test the rotors using a non-destructive testing method before and after the spin tests, to understand if any changes occur within the structure that could result in the fatigue and/or failure of the rotors.
Stay tuned - I’ll post the results next month.