The MTR Corporation announced on Friday that it will resume trial runs of Express Rail Link trains after an earlier derailment incident. However, a maintenance track involved in the incident will remain closed until improvements are made.
The tests were suspended on April 3 after four wheels on a carriage became detached from the tracks during a trial run at the Shek Kong depot in the New Territories. The corporation launched an investigation and reached a consensus with the government to resume trials.
The investigation found that three wheels on the right side of the last cabin had shifted downwards, and one on the left side shifted upwards. The derailments measured between 2.2 and 3.3 inches (5.58cm – 8.38cm) horizontally.

The corporation said experts attributed the incident to the uniqueness of the track at the depot, which features the only the curved rail section supported by an I-beam metal structure.
At the specific spot, the I-beam was slightly deformed and widened, after it had been pressed repeatedly under use since last April.
All three other tracks were straight and in good condition, the corporation said, and no such I-beam structures were needed on the main track.

Lawmaker Michael Tien, chair of the Subcommittee on Matters Relating to Railways, said consultants for the MTRC had clearly made miscalculations for the I-beam, causing the deformation.
“The MTRC has to explain what the mechanism was to monitor such calculations – it seems there isn’t any,” he said.
He said the maintenance track’s curved design was rare, and a more traditional design should be used.

Lawmaker Tanya Chan said although it was an isolated incident, the distance involved in the derailment was large.
She said she was concerned whether similar cases may occur on other tracks, and said the MTRC should reveal who the contractor was manufacturing the track.
“The government should also explain whether it has accepted the MTRC’s explanation, or whether it will conduct an independent investigation,” she said.
Chan added that, although she did not support the controversial joint checkpoint arrangement, she hoped the trains would be safe, and accidents would be reviewed objectively and professionally.