The Piccadilly line has been dubbed the “Purgatory line” after a spate of frustrating delays and suspensions.
The key Underground line - which is used for one in 10 of all Tube journeys - has been suspended in full or in part on 70 occasions between June 7 and July 7, Transport for London has disclosed.
TfL has not published detailed information on Tube delays and reliability since before the pandemic, despite the London Underground accounting for more than half of all rail journeys made in the UK on a daily basis.
But TfL’s “network” figures show that, in the most recent period from June 22 to July 19, only 90.1 per cent of scheduled kilometres on the Piccadilly line were completed during the week – less than other “deep level” lines such as the Victoria, Northern, Jubilee and Central lines.
One north London commuter, who alerted The Standard to the “practically unusable” state of the line during rush hour, said: "The Piccadilly line is broken.
“It has been unreliable for so long now with countless signal failures and long gaps in the service, not to mention the seemingly endless weekend closures.
“TfL's failures must be hitting the fragile economy as many thousands of us hard-working commuters are late for work and miss appointments. It should be renamed the Purgatory Line.”
Between last November and January this year, there were long waits between Piccadilly line trains due to many suffering wheel damage caused by excessive leaf fall in west London.
The TfL data, released in answer to a freedom of information request, reveals that many of the recent interruptions in service on the Piccadilly line were only for a matter of minutes.
However, the line was suspended for 30 minutes or more on 17 occasions – including seven periods of an hour or more.
The three longest suspensions – of three hours 33 minutes, four hours six minutes and five hours 53 minutes – all happened on July 4 when there was a blaze in a railway arch at South Harrow, beyond the control of TfL.
There are meant to be 24 trains an hour in each direction on the Piccadilly line during the rush hour - meaning hundreds of services will have been delayed or cancelled.
Reasons for other part-suspensions included signal failures at Hillingdon, Hyde Park Corner, Ruislip, Ickenham, Southgate, Barons Court and Northfields.
TfL also had to contend with a casualty on the tracks, a trespasser, faulty trains, fire alerts at Hatton Cross, South Kensington and Ealing Common, and planned evacuations at Heathrow.
Only the Northern and Central line trains cover more distance on a daily basis than those on the Piccadilly line, showing how vital it is as a means of keeping the capital connected, including to the West End and Heathrow airport.
But its trains are 50 years old and a long-awaited £3bn fleet of 94 new trains – which will become the first air conditioned “deep level” Tube trains in London - has been delayed by up to a year.
The first new train is not expected to enter service until the “second half of 2026”, The Standard revealed last month.
Earlier this month, TfL commissioner Andy Lord denied that the new trains – which have different geometry to the existing 1973 fleet - had been delayed because they didn’t fit in the Tube tunnels.
London mayor Sir Sadiq Khan, in a recent written answer to the London Assembly, said the testing of the first of the new trains had been delayed “due to some challenges associated with the design, build and commissioning” but was due to begin “on the railway from August 2025”.
Sir Sadiq added: “While the Piccadilly line remains in service for most of this work, there will be some disruption due to work which needs to be carried out as part of planned weekend closures, but a lot of the testing will be carried out overnight to minimise disruption to customers.”
There will be no Night Tube between King’s Cross and Heathrow overnight on Friday August 1 and no service on the line on Saturday August 2 between King’s Cross, Osterley and Uxbridge, including on the Night Tube.
Further part closures are planned over the weekend of August 16-17, September 13-14, 20-21, and 26-28 and on various other weekends in October, November and December.
Sir Sadiq has also revealed plans for the new Piccadilly line trains to stop at Turnham Green – something that only happens early in the morning and late at night.
He said: “It is proposed for trains to call at Turnham Green after the line has been re-signalled and the fleet further expanded under phase 2 of TfL’s Piccadilly Line Upgrade.
“This would enable higher frequencies, faster journey times and would unlock the capacity needed for trains to stop at Turnham Green without impacting service levels elsewhere. However, this is not currently a funded project.”
