NTSB identifies signal failure in fatal D.C. Metrorail collision
The National Transportation
Safety Board issued nine safety recommendations, six of which are urgent, to address
concerns about the safety of train control systems that use audio frequency
track circuits. The recommendations are the result of NTSB’s ongoing investigation
into the collision between two Washington Metropolitan Area Transit Authority trains
on the Red Line near the Fort Totten station in Washington, D.C., on June 22,
2009.