Postmortems

Finding a rogue train on the circle line (2016)

A data analysis investigation into a series of incidents on the Singapore circle line, where trains would apply emergency braking.

The subsequent press release:
LTA | Joint News Release by the Land Transport Authority (LTA) & SMRT -…

  1. After several weeks of investigations, a joint team comprising the Land Transport Authority (LTA), SMRT, the signalling system manufacturer Alstom, the Infocomm Media Development Authority (IMDA), the Defence Science & Technology Agency (DSTA), DSO National Laboratories, the Government Technology Agency of Singapore (GovTech) and electro-magnetic interference specialist Rohde & Schwarz, has traced the source of the signalling problems on the Circle Line (CCL) to an intermittent failure of the signalling hardware on one train, Passenger Vehicle 46 (PV46).

  2. Between 2 and 6 November 2016, this intermittent hardware failure had caused about 100 occurrences of loss of signalling communications on trains travelling in the proximity of PV46. The loss of communications on these trains resulted in their emergency brakes being automatically activated, which is a safety feature. Our ongoing investigations indicate a strong likelihood that intermittent hardware failure on PV46 was also the cause for the about 200 occurrences of loss of signalling communications on CCL trains between 28 August and 2 September 2016.

via Numberphile on Marey charts.

1 Like