A top railway official in the South Western Railway had earlier this year flagged flaws in the interlocking system and warned of disaster if the mistakes were not rectified.
The officer was referring to the major train accident that was averted on February 8 this year due to an alert locomotive pilot on the Bengaluru-New Delhi Sampark Kranti Express at Hosadurga Road Station, Mysuru Division.
Principal Chief Operation Manager (PCOM) of South Western Railway, Hari Shankar Verma, in his letter to his higher officials had said that a serious unsafe incident had happened at Hosadurga Road station of Birur-Chikkajajur section of Mysuru division on February 8, 2023, involving Train no 12649 Sampark Kranti Express leading to a condition where a collision with down goods train approaching Hosadurga station was averted.
"The Hosadurga station incident indicates that there are serious flaws in the system and contravenes the essence and basic principles of interlocking. The electronic signal maintainer attempts to rectify the signal error after bypassing rules and procedures," he wrote in his letter dated February 9.
"It was strange that the route of dispatch was set and the starter was taken off, PLCT was given, but point no : 65A automatically set in the wrong direction (down direction)," he wrote. A PLCT is a Paper Line Clear Ticket, which is used in special circumstances and allows a train to enter a block section.
Verma mentioned that the electronic signals maintainer apparently bypassed the electronic interlocking system, which could lead to a collision of Sampark Kranti train with the goods train. "Due to the alertness of the loco pilot, the train was stopped before entering the wrong line (Down line) and averted a major disaster…” he wrote in the letter.
The incident indicates that there are serious flaws in the system, where the route of dispatch gets alerted after a train starts on signals with correct appearance of route in the Signal and Telecommunication Panels. This contravenes the essence and basic principles of inter-locking, he said.
He also warned that if the signal maintenance system was not monitored and corrected immediately, it could lead to “re-occurrence and serious accidents”.