Human error could be to blame for Hong Kong cable car'splunge

Jun 13, 2007, 12:30 GMT

Hong Kong - Human error may be to blame for a cable car cabin plunging 50 metres to the ground in Hong Kong, engineering experts said Wednesday.

The cabin, capable of carrying up to 17 people, was empty when it broke free and fell the equivalent of 13 storeys from its cable on the Ngong Ping 360 tourist ride on Lantau Monday evening.

The accident took place during a test run at 8 pm, an hour after the 5.7 kilometre ride that takes people hundreds of metres above sea and steep hillsides to the Big Buddha statue at the top of the island, had closed.

The ride was closed indefinitely Tuesday pending an investigation which will include experts from overseas.

University of Hong Kong professor of engineering Soh Ai-kah said he believed the most probable cause was human error and that the car had not been re-attached to the cable properly after an annual inspection last week.

Lo Kwok-keung, of the Polytechnic Univeristy's department of mechanical engineering, who carried out a visit of the site following the accident, agreed.

'I believe the workers failed to tighten the screws well and they did not check them,' he told local media. 'After a few days, the screws loosened more and failed to hold the cabin when it swung.'

However, cable car operator Skyrail said Wednesday it was too early to draw conclusions on the cause of the accident, stressing that the company welcomed the government's independent investigation.

'It is early days. It is premature for me to make any assumptions yet,' said Skyrail chief executive director Bill Calderwood.

'What we have to do is to see what the investigation throws up and once we have identified that we can then start to see what the rectification programmed should be.'

Meanwhile, it emerged that a company had withdrawn its bid to build the cable car because it did not think the two-wire cable system which was chosen for the ride was suitable given the length of the journey.

In documents quoted by the South China Morning Post which were sent to the MTR Corporation in 2002, Austrian company Doppelmayr said a three-cable system was more suitable.

'The risk of operational failure as well as the efforts required for a restart following a shutdown in gusty or even hurricane-like winds are much higher than compared with a tri-cable system,' Doppelmayr wrote.

The accident was the most serious setback for the 125-million-US-dollar attraction, which has been dogged by a series of mishaps which began even before it opened last September.

Technical problems delayed its original opening for two months and were followed after its opening by a number of incidents on the cable car ride in which passengers have been stranded for up to two hours by mechanical problems.

Accidents involving cable car cabins falling from the cables that carry them are rare but tourist industry leaders in Hong Kong fear the accident will affect people's confidence in the ride.

In 1976, a steel cable snapped on a cable car at the ski resort of Cavalese, Italy, killing 42 people including 15 children.