2 HN users recommended this explainer2 months2015–2022score 2
Years with an HN recommendation, 2007–2026
Cited as a view into how outdated and error-prone NYC subway signaling is, and how antique interlocking systems work.
An MTA video on communications-based train control, the system meant to replace the New York City subway's century-old signaling. It also shows the mechanical interlocks and signals in use today.
“Well made video that helps understand the interlocks - if you like antique systems!” (HN, 2018)
"They even put out a video that gleefully shows off the worst stuff. Look at how broken it is! Look at how old!" [this video] Well made video that helps understand the interlocks - if you like antique systems!
Explains interlocks in antique subway signal systems
There is this[1] video from the MTA that goes into the signaling system, which is extremely old and in the process of getting updated in certain sections. [1] [this video]
Yes - at some of the stations the people directing the trains only know when it has left a station, and when it gets to the next one. Some of it is still controlled with vacuum tubes and switchboards. The person featured in this video ruffled quite a few feathers when it was released: [this video]
Not all of the NYC subway has ATS. The current signals being replaced by CBTC date from the 1930s, and are mechanically operated. They are literally historical relics. [this video]
Shows the 1930s mechanical signals being replaced by CBTC
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