London Underground doesn&#x27;t yet have CBTC on the complicated lines, though it&#x27;s in progress and due to be completed in 2022. The cost is over £5 billion, which based on the numbers in the article doesn&#x27;t seem a likely level of investment for NYC.<p>They try and explain it to the public: <a href="https:&#x2F;&#x2F;tfl.gov.uk&#x2F;campaign&#x2F;tube-improvements&#x2F;behind-the-scenes&#x2F;signalling" rel="nofollow">https:&#x2F;&#x2F;tfl.gov.uk&#x2F;campaign&#x2F;tube-improvements&#x2F;behind-the-sce...</a>