Dear Lewis Gates,
Our ref: FOI-1163-2425
Thank you for your request received by Transport for London (TfL) on 10 July 2024 asking for information about the operation of sub-surface trains.
Your request has been considered under the requirements of the Freedom of Information Act 2000 and our information access policy.
I can confirm that we do hold the information you require.
CBTC (communications-based train control) now encompasses the Circle line, Hammersmith and City line, District line east to Upminster and Metropolitan line north to Finchley Road. The transition zones to legacy are Finchley Road, Fulham Broadway and Barons Court. The remaining areas of Metropolitan Line north and District Line west remain legacy systems.
If you are not satisfied with this response, please see the attached information sheet for details of your right to appeal.
Yours sincerely,
Tahsin Prima
FOI Case Officer
General Counsel
Transport for London