Our ref: FOI-1082-2425

Thank you for your request received by Transport for London (TfL) on 03 July 2024 asking for the availability of rolling stock (trains) on the London Underground network.

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 some of hold the information you require. You asked:

I’d like to know how the availability of rolling stock (trains) on the London Underground/tube network has changed over the past 10 years. 

Excluding new lines (e.g., the Elizabeth Line) I’d like to know, for each year, the average number of trains in use (not out of service or in for repair) during peak and off-peak times throughout the network. 

I am particularly interested in the Northern Line and Central line, which I believe are operating below capacity due to a lack of serviceable trains and carriages.

Please see attached to view the requested information. However, please note that we do not hold the information requested directly and cannot calculate it to the level of detail requested. 

Fleet disruptions are categorised internally No OK stock (NOOK) incidents. The definition is as follows: Shortage of available train(s) for service against the timetabled requirements as a result of any kind of incident where a train has not been offered for service. Typically, these incidents are assigned to each peak (morning and evening) so a missing train will cause 2 NOOK stock counts in a day. We have compared the NOOK stock count to the timetable requirements and provided a percentage of timetabled trains available.

If you wish to calculate the percentage of each fleet available, you should be able to calculate this using the attached data and the size of each fleet which is available in the Rolling Stock Data Sheets available here: https://foi.tfl.gov.uk/FOI-4043-2324/Rolling_stock_Data_Sheet_4th_Edition.pdf. This should be a simpler calculation as the fleet sizes is constant unlike the timetable requirements which vary by day.

Also note, there is data available on the TfL website (https://tfl.gov.uk/corporate/publications-and-reports/underground-services-performance) where you can see our Service and Kilometres Operated by line in recent years for an indication of the level of service we have been providing. We hope this helps.

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