§ Mr. Hill
This is an operational matter for London Underground (LUL) but they have provided the following information.
LUL keep a range of records of incidents on the London Underground system. They do not use the term "major breakdown" as such, but the most appropriate measure to refer to is the record LUL have of operational or mechanical incidents which give rise to delays to passengers of over one hour. For the purpose of answering this question a "major breakdown" is therefore taken to be an incident which gives rise to delays to passengers of over one hour on the system, and is related to a failure of infrastructure or assets on the system.
The table sets out, by line and by main categories of infrastructure or asset failure, the number of such incidents during the 12 months to 14 October 2000. The incidents are in practice very varied, and categories may inevitably overlap to some extent: for example, track failures may be closely linked to signal problems, and train or track failures may be linked to power problems.
The table excludes incidents which are not related to a failure of infrastructure or assets on the system. These include a wide range of instances: for example delays due to passengers reporting the smell of burning, or water on platforms, or broken glass roof panels at a station.
Failures Train/signal/track Escalator Lifts Power Bakerloo Line 19 8 36 18 Central Line 17 8 — 8 District Line 13 — — 11 Jubilee and East London Lines 8 3 — 4 Metropolitan and Circle (C and H) 11 — — 2 Metropolitan and Circle (Main) 8 3 — 10 Northern Line 7 48 1 16 Piccadilly Line 7 10 4 9 Victoria Line 9 73 — 11 Waterloo and City 5 — — — Total 104 153 41 89