Federal Transit Administration Acts Quickly on NTSB Plea
A "Dear Colleague" letter from Administrator Peter Rogoff asks all transit rail operators to add redundancy if their train control systems are susceptible to a single-point failure.
The Federal Transit Administration has moved quickly in response to a National Transportation Safety Board recommendation by sending a "Dear Colleague" letter in which FTA Administrator Peter Rogoff asks all transit rail operators to add redundancy if their train control systems are susceptible to a single-point failure. The urgent recommendation was made as NTSB investigates the June 22 collision of two Washington Metropolitan Area Transit Authority trains, an accident that killed nine people and injured 70 others.
NTSB Member Debbie Hersman discussed the safety redundancy of WMATA's automatic train control system in testimony Tuesday before the U.S. House Committee on Oversight and Government Reform's Subcommittee on Federal Workforce, Postal Service and the District of Columbia. The collision demonstrated WMATA's system is susceptible to a single-point failure because it did not stop a train when detection of a preceding train was lost, she said. "Automatic train control systems are supposed to detect the presence of all trains at all times," Hersman said, "but in the unfortunate event that the system fails, there should be a built-in safety redundancy, like a real-time alert, to prevent trains from hitting one another."
Rogoff was confirmed as FTA administrator on May 21. "Specifically, we are asking that all train operators that have train control systems capable of monitoring train movements determine whether their systems have adequate safety redundancy if losses in train detection occur," his letter states. "If a system is susceptible to single point failure, we urge you take corrective action immediately to add redundancy by evaluating track occupancy data on a real-time basis to automatically generate alerts and speed restrictions to prevent train collisions. . . . I request that you focus immediate attention on this important safety concern. For the purposes of verification, we will be following-up shortly with requests for information on specific train control systems and what compensating systems you have been able to develop if you have determined that a single point failure could occur. We also expect to serve as a clearinghouse to share information regarding industry best practices in addressing this issue."