It’s a crushing inevitability that the entry into service of new trains will be delayed and the latest system to be impacted by this is the Docklands Light Railway. The latest TfL Commissioner’s Report (June 2024) has a brief section on the DLR rolling stock replacement programme and although it doesn’t say that their introduction has been delayed it does admit to some challenges.
The new trains are being built by CAF in Spain and are part of the Inneo family of Metro trains the company offers. In total there are 54 on order (which includes an add-on thanks to funding from the Housing Infrastructure Fund looking to further development in the Docklands) and its also been confirmed that there are 30 already built (although just three are in London).
Those which have been built are under various stages of testing and this has included some runs of those which have been delivered to Beckton Depot on the DLR network during planned closures.
Originally due to be introduced into service from early 2024 this date has been delayed and TfL are now saying that “work continues to prepare for the first train in revenue service later this year”.
In the report it is stated: “While we have experienced some challenges with this phase [testing], we continue to work collaboratively with our suppliers and operator to mitigate this.” No details are given as to what the challenges are but it is said that they should all still be in service by 2026 as planned.
Connected to the introduction of the new trains are works to enhance Beckton Depot. This includes new sidings and they should be completed by the summer. Power works have also been completed on three routes to enable the new trains to run whilst further work is underway at Blackwall Station to add a second entrance with the piling now complete.
Finally, a tender has been issued for more expansion at Beckton Depot (required because of the additional trains now ordered).
The fleet of new trains will both replace the B90, B92 and B2K trains as well as providing additional capacity. With the delays in the introduction of the trains there have recently been timetable changes which have seen more two car trains running because of shortages with the reliability of those older vehicles now starting to reduce.
I regularly read about older vehicles being blaimed for bad reliability. However the real cause of bad reliability is poor maintenance, whatever the age of the vehicle.
With good maintenance and overhaul practices there is no reason a vehicle should not carry on in service indefinitely.
If a train needs replacing after a little over 20 years, I would be asking questions of the vehicle’s original builders and also of those maintaining them.
There comes a tipping-point where cost and availability of spares outweighs the cost of replacement.
When that point is reached depends on a lot of factors – rate of needing spaces could be affected by mileage, passenger loadings, environmental conditions, as well as Maintenance.
I do agree though that original build quality is a big factor – experience on both light and heavy rail throughout Europe, not just the UK says the only reason you buy CAF is because they are cheapest (e.g WM Urbos, Northern Rail 195/331s, TFW 197s, TPE mk5 coaches), so I do worry about the durability of the new DLR trains being worse than those they are replacing.
You are correct in saying that good maintenance assists in continuing reliability. However there comes a point in the life of a vehicle where component obsolescence means spares cannot be obtained and failed electronic equipment cannot be repaired. At that stage in its life a view has to be taken as to whether it is more cost effective to look at re-engineering the vehicle or replacing it. Most rail vehicles are intended to have a book life of 30 years with a midlife refurbishment at around 12 to 15 years or so. However obsolescence will start to become a big
problem at around 10 years and by the time refurbishment is required many of the electronics may need complete replacement. The DLR units being replaced by the new units have reached this stage in their lives and in some cases reached their book life so replacement makes sense.