Written Reply by Minister for Transport Khaw Boon Wan to Parliamentary Question on Lessons for Singapore from October 2018 Hong Kong MTR Breakdown
20 November 2018
This article has been migrated from an earlier version of the site and may display formatting inconsistencies.
Mr Gan Thiam Poh asked the Minister for Transport
a. what are the lessons that can be learnt from the Hong Kong MTR breakdown in October 2018 as a result of a system glitch; and
b. what measures have been put in place to prevent such incidents from occurring in our MRT system.
Reply by Minister for Transport Khaw Boon Wan:
1. In the morning of 16 October 2018, train services on four major Hong Kong MTR lines were affected for up to six hours. Train services remained open but had to operate at reduced speeds and lower frequency, resulting in longer travelling times for commuters.
2. Investigations by Hong Kong authorities are still on-going. Initial findings released by the Legislative Council Panel on Transport indicate that the incident was caused by a signalling system failure. There was a loss of synchronisation between the signalling systems used by the four rail lines. The signalling systems of the four lines are inter-connected by design, and are provided by two different suppliers, Alstom and Siemens. The suppliers use different system settings. For normal functioning, the data transmission from these different signalling systems must be seamlessly synchronised at all times to ensure that the two systems communicate with each other for delivering train control commands. Inter-connection of the two systems is achieved through the computers which connect the systems. Unfortunately, the synchronisation failed on 16 October. It was rectified only after the operator isolated the connections between the lines and re-booted all computers. These are preliminary findings and are subject to further investigation which is on-going.
3. The likelihood of a similar loss of synchronisation between the signalling systems of our different MRT lines is low. First, the signalling systems for the Circle Line, Downtown Line and North East Line operate as separate systems. They do not require any synchronisation. Second, although the North-South and East-West Lines share the same signalling system, it is provided by the same supplier, Thales, and have the exact same settings. Hence, there is no need to synchronise across different systems from different suppliers.
4. However, the Hong Kong incident is a timely reminder that MRT lines are highly complex engineering systems. We must never let our guard down. Our train operators must develop deep engineering expertise in the systems we procure. They must devote sufficient resources to engineering and give top management attention to operation and maintenance. As the MRT network upgrades and expands, different generations of technology are acquired and have to work seamlessly together. The re-signalling of the North-South and East-West Lines is an example of how complicated the project is. The re-signalling of the North-South Line was eventful precisely because of such complications. The lack of engineering hours to carry out essential testing added to the already challenging task. After the train collision incident in November 2017, the public supported more engineering hours through ECLO – Early Closure and Late Opening. That has made a significant difference to the re-signalling project for the East-West Line, which has been carried out more smoothly as compared to the re-signalling project for the North-South Line.
5. Another lesson from the Hong Kong incident is the importance of standardisation, I made this point in a recent speech to our engineers. As our rail network becomes more extensive, we need to think about how we can better standardize systems across the rail network. By 2030, we will have eight MRT lines. Is it wise to end up with eight different systems, whether it is for signalling, or trains, or power? If we do, our engineers will have to learn eight different systems, multiplied by as many different assets. This will not be a good use of limited engineering talent, not to mention the higher holding cost of spare parts, loss of economies of scale and greater complication in operations.
6. The Hong Kong incident is unfortunate. Each incident is a reminder that unplanned incidents can happen to the most competent operator. We will continue to monitor the outcome of the investigations of the 16 October incident in Hong Kong, and put in the necessary measures to mitigate any similar vulnerabilities in our own rail network.
