At approximately 7:15 am AEDT, on 31 January 2003, south of Waterfall, New South Wales, Australia, an Intercity Tangara G set derailed on a curve at high speeds when the driver had a heart attack, and the deadman's brake failed. The incident killed seven people aboard, including the train driver, and injured 40. The accident is notably remembered by systems engineers due to the poorly designed safety systems.
Incident On the day of the disaster, a Tangara interurban train service, serviced by set G7, which had come from Sydney Central station at 6:24 am, departed Sydney Waterfall railway station moving south towards Port Kembla station via Wollongong. At approximately 7:15 am, the driver suffered a sudden heart attack and lost control of the train. The train was thus travelling at 117 km/h (73 mph) as it approached a curve in the tracks through a small cutting. The curve is rated for speeds no greater than 60 km/h (37 mph). The train derailed, overturned and collided with the rocky walls of the cutting in a remote area south of the station. It was reported that the rescuers had to carry heavy lifting equipment for more than 1.5 km (0.93 mi) to reach the site. Two of the carriages landed on their sides and another two were severely damaged in the accident. In addition to the seven fatalities, many more passengers were injured. The subsequent official inquiry discovered the deadman's brake had not been applied. The train guard's solicitor stated that the guard was in a microsleep for as much as 30 seconds, just prior to the accident. The human-factors accident investigator determined the organisational culture had the driver firmly in charge, making it psychologically more difficult for the guard to act.
Causes of the accident
Tangara trains have a number of safety and vigilance devices installed, such as a deadman's brake, to address problems when the driver becomes incapacitated. If the driver releases pressure from this brake, the train will safely come to a halt. The train in question was a four-car Outer Suburban Tangara set, numbered G7 and fitted with a Mitsubishi Electric alternating current traction system for evaluation purposes. The driver was in the leading driving carriage and the guard was in the rear driving carriage, in between which were two non-driving motor cars. On this service, the guard, who could have applied the emergency brake, and the deadman's brake were the main safety mechanisms in place. The train was later found to be travelling in excess of 117 km/h (73 mph) as it approached the 60 km/h (37 mph) curve where the accident occurred. Neither the deadman's brake nor the guard had intervened in this situation, and this excessive speed was found to be the direct cause of the accident. Deficient training of train staff was also found to be a contributing factor in the accident. Train G7 did not re-enter service. It was scrapped in 2005 due to the damage sustained in the accident as all four cars were damaged beyond repair. These were the official findings of the NSW Ministry of Transport investigation of the accident. A report of the accident, managed by Commissioner Peter McInerney, was released in January 2004.
Systemic causes and ignored technical problems It was reported that G7 was said to have been reported for technical problems "possibly half a dozen times" and had developed a reputation amongst the mechanical operations branch, saying the problems were "normal" for the set in question. During the six months leading up to the accident, three reports of technical problems were made. The inquiry found a number of flaws in the deadman's handle (which was not implicated in the accident) and related to the deadman's pedal:
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