Trains on the Hong Kong MTR operate as fixed consist – each made up of a set of carriages coupled together, which never get broken apart except for inside the maintenance depot. However each train still has a coupler at each end, to allow for failed trains to be pushed out of the way, such as in this video.
Here we see two 8-car long Adtranz-CAF EMUs at Kowloon station on the MTR Tung Chung Line, coupled together to form a 16-car long train. A defective carriage on set V607 saw the train unable to move under it’s own power, so the train behind (set V612) was emptied of passengers, and then used to push the failed train out of the way.
The train was then pushed to Nam Cheong Station, where it was parked on the Airport Express line tracks, resulting in these trains being routed via the Tung Chung Line platforms.
Both videos are by mtrA381382 on YouTube, and were filmed on 15 October 2015.