Winds capable of disrupting the Ngong Ping cable car on Lantau hit just 23 hours a year on an average of seven days when taking into account just operating hours, according to Observatory data from the past four years. This is far less than the annual average of 55.3 days Ngong Ping was affected by high-speed winds between 2002 and last year. 'The 55-day average refers to wind speeds throughout the whole day. But as the cable car operates between 9am and 6.30pm, we only look at wind speeds during this time period. This works out to be an annual average of seven days for a total of 23 hours, or slightly over three hours a day,' Secretary for Economic Development and Labour Stephen Ip Shu-kwan told lawmakers yesterday. These weather conditions include persistent wind speeds averaging more than 90km/h over a 30-second period and wind gusts topping 135km/h for at least one second. Mr Ip added that similar safety parameters are adopted by some overseas cable car systems. The observatory said July was the windiest month, with an average of 9.3 days or 62 hours of winds exceeding 90km/h. The four-month summer season, between June and September, tends to be the windiest at Ngong Ping. Service was suspended during trials three weeks ago due to gale-force winds. Asked by tourism chief and legislator Selina Chow Liang Shuk-yee whether alternate arrangements would be made to transport visitors to other Lantau attractions in the event the cable car was disrupted, Mr Ip said the government would liaise with Skyrail-ITM, which operates the ride, and the MTR Corp, which owns the attraction. The Lantau tourist attraction postponed its opening last weekend pending further tests to iron out technical problems due to a computer programming glitch that affected the spacing of the cabins.