Angular section aluminium alloy track, length 255 cm, with staggered air holes, supported on two light alloy castings positioned 45 cms from each end of the track. One support has two-point contact and other one-point contact for lateral and horizontal adjustments for which a knurled screw is provided. Large catapult arms with slots for elastic bands are fitted to each end of the track. A pulley to one end of the track enables experiments involving acceleration under a constant force to be investigated. Identical end caps enable air to be introduced from either end of the track, bung being supplied to close the end not being used. The vehicle buffer attachments and clamping screws are matt black to help interpretation os stroboscopic photographs.