THE Transport Advisory Committee has called on bus companies to take out of service a particular model of double-decker bus after one broke down on the Tuen Mun Highway when its rear wheels came loose. Dr Raymond Ho Chung-tai made the demand after the incident yesterday morning involving a Kowloon Motor Bus (KMB) vehicle's halfshaft which broke, resulting in loosened right rear wheels. 'We are very unsatisfied, we are talking about public safety. Bus companies should not use that particular model for the time being,' he said. The committee chairman also criticised KMB over what he perceived as a lax attitude to passenger safety even though there were no injuries yesterday. 'These are not isolated incidents that can be attributed to a few individuals' human errors. It is time KMB faces the fact that it may not only be maintenance procedures that is inadequate,' Dr Ho said. 'They need experts to look at whether there are basic design flaws in these vehicles. We are talking about a bus that has a carrying capacity of more than 100 passengers so it is critical to ensure public safety.' Bus No 59A was heading from Tuen Mun to Kowloon when the driver noticed the displaced rear wheels. All three lanes of the Tuen Mun Highway between Yau Kam Tau and Sham Tseng were closed off for about an hour. Lui Po-chiu, KMB traffic manager, said: 'The situation was likely caused by metal fatigue. It is very difficult to break a shaft, they are lifetime parts that are not usually changed. But if that is the case, then there may have been some production problems.' He said KMB had no plans to pull any of the three-axle buses from active service until a government report had ascertained the cause of the incident.