Washington Metro signaling and operation

This gives individual train and station operators the information they need to safely and efficiently perform their tasks.

The Automatic Train Protection sub-system uses coded track circuit technology originally supplied by Rochester, New York-based General Railway Signal when the line was constructed in the 1970s.

It is a life-critical system that provides a continuous stream of information to the train regarding the maximum safe speed via the running rails.

[1] The system works via a series of track mounted balises, which function as information beacons transmitting a speed code to the train as it passes overhead.

[2] This speed would have been safe during dry weather, but because of ice or snow, trains required additional stopping distance, which was not provided for by the ATC system.

Metro Center, Gallery Place, L'Enfant Plaza, and Fort Totten have two RTU numbers: one for each level.

[citation needed] Fixed signals are only present at interlockings, and consist of three lamps: two red and one lunar.

[citation needed] Tracks are divided into block sections, which can only be occupied by one train at a time, a method to protect against collisions used by most railway systems worldwide, but there are generally no fixed signals to protect block sections (signals tend to be only at beginning/end of route and just before track switches).

Similar signals are also in place on the Baltimore Metro SubwayLink, the PATCO Speedline, and the Miami Metrorail.

Two trackside signs exist: The "S"-Sign is posted at revenue tracks and indicates to the operator that a station is ahead.

In 2008, Metro began planning to acquire sufficient quantities of the new 7000-Series cars to run 100% eight-car trains.

[7] Metro also tested eight-car trains on the Yellow and Blue lines in preparation for increased service during the 2009 inauguration of Barack Obama.

[8][9] However, by early 2010 riders began to lose faith in WMATA's "promise" to implement 100% eight-car trains.