NYC subways slowly upgrading from 1930s-era technology
New York City's subwaysthe nation's biggest mass transit networkserve more than 6 million daily riders who depend largely on a signal system that dates back to the Great Depression.
Antiquated electro-mechanics with thousands of moving parts are still critical to operations. Dispatchers still monitor most trains from 24-hour underground "towers," and they still put pencil to paper to track their progress.
That eight-decade-old system is slowly being replaced by 21st-century digital technology that allows up to twice as many trains to safely travel closer together. But there's a big caveat: It could take at least 20 years for the city's 700 miles of tracks to be fully computerized.
Of the subway system's almost two dozen major lines, just one, the L linking Manhattan and Brooklyn, currently operates on new, computerized, automated signals. And the modernization of the No. 7 line from Manhattan to Queens has begun, to be completed by 2017.
Read more at: http://phys.org/news/2014-12-nyc-subways-slowly-1930s-era-technology.html
In this Dec. 16, 2014 photo, MTA train service supervisor Tweh Friday monitors a subway interlocking switch and signal control board, at the 4th Street MTA Supervisory Tower in New York. The 1930s technology of switches and relays requires a human operator to use hand levers to manually route trains and keep them separated at safe distances. (AP Photo/Bebeto Matthews)