Crossrail has confirmed that it plans to pause all train testing in the tunnels during August to allow the construction teams to catch up with the backlog caused by the Covid lockdown.
During the lockdown, a lot of validation work was completed and paperwork submitted for regulatory approval, but most of the finishing works in the stations and access shafts had to be put on hold.
However, the lockdown gave the teams working on site to spend some time planning a way to reduce the delays caused by the lockdown. Construction teams who were busy just trying to get work done now had some spare time to think, and that’s where the blockade comes in.
At the moment, the various sites work is split between finishing construction and finishing testing — but generally, you can’t do both together, so they’ve been working in shifts. A few days for the testing teams and a few days for the construction teams.
The 5-week blockade will see all train testing in the tunnels come to a halt, and then the construction teams will work 24-hours a day in three shifts to accelerate the completion of the construction phase.
The blockade is in part possible thanks to the train testing having reached a point where they are on the cusp of switching to full trial running – that is effectively running the trains in a live simulation of how they will operate when the line is carrying passengers.
Testing of the latest version of the train software (version PD+11) will conclude prior to the blockade and will mean that Crossrail has a viable software product available for Trial Running. The next evolution of software, referred to as TR2, will be ready for Trial Running.
They are still testing the tunnel systems as well though, and during August, some 25 different scenarios need to be tested, ranging from a reboot of the central section’s signalling to simulating a High Voltage power outage.
Once the final tests are completed, and they have regulatory approval from the Office of Rail and Road (ORR), then trial running can start – probably this Autumn.
Elsewhere in the construction sites, the ventilation shaft at Limmo, near Canning Town has now completed the safety-critical works and they are in the final stages of signing off all the assurance paperwork ahead of handing over to Rail for London, the company that will run the Elizabeth line when it opens.
They’re at the point where seven of the ten portals and shafts are nearing completion, with three to be handed over in the coming months.
Bond Street station is still delayed, and last month Crossrail took direct control of the building site from Costain Skanska to complete the works and get the station ready to support trial running of the trains.
As for the opening date of the Elizabeth line, the Crossrail board will see a report into how the lockdown has affected the timeline later this month, so we are likely to have an announcement next month about what, if any, delay there might be.
At the moment, the line is due to open in the summer of 2021.
I really do wonder what the position re crossrail would have been in the Tories hadn’t cut it’s budget by £1bn nd extending the then expeceted completion date in 2010.
The bulk of the cost cuts were taking advantage of lower supply costs following the 2008 recession and the one-year opening delay was pretty much expected at the time as the original opening date was felt to be unachievable in engineering terms.
“The next evolution of software, referred to as TR2, will be ready for Trial Running”
So still further major release(s) of software to come before it’s ready to go live.
I treat software testing as binary: done/not-done, so there’s significant of work still to do, and must be some risk of further delay.
Presumably the next releases (“Live testing” & “Live” ??) are being worked on already, but any fixes arising from TR2 will need to be incorporated.
Crossrail themselves identified “The main areas of programme risk and uncertainty are currently contractor productivity, software testing for the train and signalling systems and systems integration
https://www.crossrail.co.uk/news/articles/update-on-progress-to-complete-the-elizabeth-line
Software testing isn’t binary – it’s a long path of many many little tests and scenarios along to sign-off, at which point even then it’s never 100% completed.
“done” in this case is acceptable to ORR and other safety authorities. It either is or it isn’t.
So “90% complete” metrics are useful but don’t allow accurate prediction of how long is left in development.
Clearly separate components can be tested, but as Mark Wild has said testing the integrated whole can bring problems.
See also Boeing Starliner
“However, the lockdown gave the teams working on site to spend some time planning a way to reduce the delays caused by the lockdown”
Does this mean they were working without a plan? Not bashing the UK here but are we legitimately bad at delivering major projects like this? We read other countries completing high speed rail, etc and the reporting on Crossrail makes us look very slow. Is there a systemic reason for this? I understand all construction isnt the same but are there UK specific reasons which make it more challenging/expensive? I’d love to know.
“Does this mean they were working without a plan?” <-- of course not. However, as in all things in life, if you have time to stop and think about things, better ways of doing them come available -- but often in life we are so busy doing that we don't have time to think if there's a better way of doing. There is tons of research over the years showing how unexpected changes to our lives result in better ways of doing things because it makes us rethink what we're doing - it's human nature, not a Crossrail or UK thing.
Berlin Brandenburg airport which should have opened in October 2011 now planned to open later this year