Drive-by-wire, or x-by-wire: all-electric controls with no mechanical or hydraulic link between the control (steering wheel, brake pedal or gear lever) and the component (wheels, brakes or gearbox). TECHNICALLY, today's car is closer to an aircraft than to a household appliance, according to Michel Faivre-Duboz, head of Renault vehicle engineering, with more electronics today on a new car than there were on the first Airbus. The problem though, says Faivre-Duboz, is that on an aircraft it is possible to have a totally secure system by duplicating or even triplicating the solutions - what is known as redundancy. Cost prohibits this for cars: controls must be kept as simple as on a cooker, washing machine or microwave (or even simpler, cynics might suggest). The adoption of any true drive-by-wire system also throws up a host of secondary issues, even supposing that all legislative hurdles are crossed.