
Commuter Rail
NTSB: WMATA Track Tircuit’s Train Occupancy Signal Fluctuating Since 2007
WASHINGTON — The National Transportation Safety Board continues to make progress in its investigation of the June 22, 2009, collision of two Washington Metropolitan Area Transit Authority (WMATA) trains on the Red Line in Washington, D.C. The Board has developed the following factual information: Two signal companies, Ansaldo STS USA (US&S) and Alstom Signaling Inc. (GRS), that designed and manufactured the automatic train control components for the WMATA system, are providing technical assistance to the NTSB investigation. As previously reported, an impedance bond (No. 15) for the track circuit where the accident occurred was replaced on June 17, five days