While out and about on the Underground this week we noticed this at Charing Cross on the northbound Northern Line platform:
The hatchings on the platform are accompanied by this sign on the wall:
And sure enough when our train arrived the leading set of doors didn’t open here.
If our memory serves correctly this has always been the case with the 95-stock on the Northern Line, so what’s going on here?
Well it all turns out it’s to do with the recent commissioning of what’s known as ‘NMA4’ or ‘Northern Migration Area 4’. This is part (4 of 6) of the project to implement Transmission Based Train Control or ‘TBTC’ on the Northern Line – which allows the trains to be driven automatically, as is already the case on the Victoria, Central and Jubilee lines. Presently on the Northern Line, the High Barnet branch and Chalk Farm to Oval are running with automation.
When NMA4 went live recently, the stopping point at Charing Cross was moved back by 2.5 metres (for reasons unknown to us at present), however the doors and the passenger announcements (CELIA) are driven by the Train Management System (TMS) which needs a software upgrade to take this into account, but this won’t be updated until around June 2014.