level of structural integrity. In the Grayrigg derailment incident, where the unit involved was travelling at a speed of and derailed at a set of points sending the carriages off the track and down a bank, one person died. Furthermore, the majority of passengers were not even seriously injured due to the carriages' structural properties. Traction systems The Pendolino's propulsion system incorporates Alstom's Onix traction drive system, which controls 12 separate traction motors, each capable of providing up to . Traction motors are suspended from the underside of the carriage bodies and connected to the driving wheels using a Cardan shaft and transfer gearbox thus lowering the unsprung mass and consequent track wear at high speeds, a feature inherited from its APT ancestor. Combined, they are capable of producing a rate of acceleration of up to 0.43 ms−2, which enables the train to accelerate from stationary to in just over 60 seconds. Power for each Pendolino is supplied in the form of 25,000voltsAC, and is delivered via the overhead catenary infrastructure installed across its route. A particularly unusual measure, which was adopted to account for the train's tilting ability, is incorporated into the pantograph, the roof-mounted mechanism which connects the train to the overhead wires; it also features an active tilting system, which moves the pantograph to a precise angle in opposition to the direction of the carriages' tilt, allowing contact with the overhead catenary to be smoothly maintained. Passenger amenities The Pendolino features a number of amenities and innovations, such as a walk-in shop in place of the traditional buffet/restaurant car and the extensive presence of passenger visual information systems, which are installed on both the inside of the car ends and on the outside of the doors themselves. In response to criticisms of the pressure-operated automatic gangway doors fitted to the Mark 3 and Mark 4 carriages (which could easily be held open by items of luggage resting on the floor sensor, allowing draughts into the passenger saloon), the gangway doors of the Pendolino have press buttons instead. To assist the boarding process, the doors incorporate automatically extending steps, which deploy when the doors open; this feature is claimed to have been first used on the APT-P. Originally, every seat had an integrated on-board entertainment system, which featured radio stations, including Virgin Radio, several BBC stations, and a number of pre-recorded music channels. Up-to-date information on the available