Give the official announcement of the MTR TWL train collision

An official investigation determined that the MTR Tsuen Wan Line (TWL) train collision on March 18, 2019, was caused by software implementation errors made by the contractor for the new signaling system89. The incident occurred during a drill for the new system in non-traffic hours8.
官方调查确定，2019 年 3 月 18 日港铁荃湾线（TWL）列车相撞事故是由负责新信号系统 8 9 的承包商在软件实施过程中出现的错误所导致的。该事故发生在非运营时段进行的新系统演习期间 8 。

Details of the Incident
事件详情

At approximately 2:44 a.m. on March 18, 2019, two non-passenger MTR trains collided near Central Station910. One train was entering the station while the other was departing through the same crossover track89. The collision resulted in injuries to the two train drivers, who were hospitalized and discharged the same day910. The incident led to a two-day suspension of train service on the Tsuen Wan Line between Admiralty and Central stations12.
2019 年 3 月 18 日凌晨约 2 时 44 分，两列非客运港铁列车在中央站附近发生碰撞。其中一列列车正进入车站，另一列则通过同一联线轨道驶出。事故导致两名列车司机受伤，他们被送医并于当日出院。该事件导致港铁荃湾线在金钟站和中央站之间暂停服务两天。

Official Investigation and Findings
官方调查及结果

Both the MTR Corporation and the Electrical and Mechanical Services Department (EMSD) conducted detailed investigations into the collision89. The MTRC formed an investigation committee and made its findings public on July 5, 2019812.
港铁公司及机电工程署均对 8 9 事故展开了详细调查。港铁公司成立了调查委员会，并于 2019 年 7 月 5 日公布调查结果 8 12 。

Cause of the Collision
事故原因
The investigations concluded that the direct cause was a programming error in the new signaling system's software, which was supplied by the contractor, Alstom-Thales DUAT Joint Venture (ATDJV)89.
调查结果显示，事故的直接原因是新信号系统软件的编程错误，该软件由承包商阿尔斯通-泰雷兹 DUAT 合资公司（ATDJV）提供 8 9 。

• A programming error introduced during a software rectification in July 2017 went undetected9.
  2017 年 7 月进行的一次软件修正中引入的编程错误未被察觉 9 。

• The error caused a failure to properly transfer data for the crossover track at Central Station when the system switched from its primary controller to a tertiary backup controller during the drill9.
  错误导致在演练 9 期间，当系统从主控制器切换到三级备用控制器时，中央站的交叉轨道数据未能正确传输。

• This failure meant the Automatic Train Protection (ATP) system could not function as required to prevent two trains from entering the same track section simultaneously, which led to the collision9. The supplier, Alstom-Thales, confirmed a software issue after re-enacting the crash in their lab13.
  这一故障意味着自动列车保护（ATP）系统无法按预期功能防止两列火车同时进入同一轨道区段，从而导致了碰撞 9 。供应商阿尔斯通-泰雷兹在实验室重现事故后确认存在软件问题 13 。

Contributing Factors
促成因素
The EMSD's independent investigation also identified several other contributing causes:
EMSD 的独立调查还确定了其他几个促成原因：

• Poorly Specified Requirements: The design requirements for the software were not clearly defined9.
  需求定义不明确：软件的设计需求没有明确界定 9 。

• Inadequate Testing: The contractor's verification and validation processes for the software were insufficient to identify the error before the on-site drill9.
  测试不足：承包商的软件验证和确认过程不足以在实地演练前发现错误 9 。

• Incomplete Risk Assessment: The contractor did not comprehensively assess the potential risks associated with the implementation of the tertiary backup controller, which was a unique feature for this specific project9.
  风险评估不完整：承包商没有全面评估与三级备份控制器实施相关的潜在风险，而这一功能是该项目特有的 9 。

• Insufficient Simulation: Simulation tests were not conducted to the maximum possible extent by the contractor before the on-site tests began9.
  模拟不足：承包商在实地测试开始前没有尽可能地开展模拟测试 9 。

Aftermath and Response
后续与应对

In response to the incident, the MTR Corporation immediately suspended all testing of the new signaling system on the Tsuen Wan, Island, and Kwun Tong lines until the root cause was identified and rectified913. The MTRC stated it would strengthen its monitoring and oversight of the contractor to ensure all recommended improvement measures were implemented8.
针对此次事件，港铁公司立即暂停了港岛、荃湾及九龙线新信号系统的所有测试，直至查明并纠正根本原因 9 13 。港铁公司表示将加强对承包商的监察，确保所有建议的改进措施得到落实 8 。