Metro takes one step back from automation (again)

Step back, doors closing. The automated system that opens doors when trains arrive at stations, which Metro rolled out on the Red Line in January, has once again been turned back off. Train operators will now resort back to manually pushing the buttons needed to open doors when trains berth to let riders on and off.

What is Automatic Door Operation?

The Metrorail system was built in the 1970’s with automation in mind. Automatic Train Operation, the system that would control and drive trains down the tracks, was the more visible of the two automated systems, and was in use from system inauguration until 2009 when Metro disabled it in response to the fatal Fort Totten train collision. (It was later determined that ATO itself didn’t cause the crash but that there were other contributing factors.)

Automatic Door Operation, or ADO for short, isn’t as prominent but still played a role in system operations from beginning up until 2008. When trains arrive at and stop in stations, this is the system which would automatically open the train’s doors so a human wouldn’t have to. Within a couple seconds, the doors would open for people to board and exit the train.

Metro disabled ADO in 2008 and blamed “electromagnetic interference” from the train power system which caused limited instances where train doors opened on the wrong sides of platforms.

But as I wrote back in January, ADO caused another problem. Train operators themselves were opening the doors either on the wrong side, or when their trains weren’t fully berthed on station platforms.

Metro implemented a manual policy in 2012 to try and help, the “Five Second Rule,” which required operators to wait five seconds before opening doors to try and ensure they were on the correct side of the train. That may have helped, but there were still instances of operators opening the wrong sets of doors.

Safety oversight spots flaws in the ADO certification process

An audit issued earlier this year by the Washington Metropolitan Safety Commission (WMSC), which oversees Metrorail safety, spotted flaws in the way that ADO came to be re-certified and re-enabled this year, which potentially played a role in this saga’s latest development.

The WMSC confirmed that Metro disabled ADO, but neither agency returned several follow-up questions about the topic before this article was published.

The WMSC’s audit highlighted a few items, one among them that the groups responsible for and that work with the Automatic Train Control system don’t communicate well enough with each other. “The siloed nature of training and technical materials, capital planning and efforts such as a return to automatic door operations or automatic train operators create opportunities for safety issues to fall through the cracks.”

Information the WMSC gleaned from Metro staff told them that one group, vehicle engineering (CENV), was in charge of the ADO restoration effort, and the engineers and maintenance teams responsible for the ATC system which supports ADO hadn’t been involved. “Any changes,” the WMSC noted, “let alone significant changes, to the ATC system are supposed to be done only with the direct involvement of ATCE [ATC Engineering]…and coordination with other departments.”

Metro also told the WMSC in response to its audit that “no hazard analysis had been conducted for the automatic door restoration project.” Staff explained that ADO is “a non-vital operation,” which they said meant it didn’t need the “highest level of safety certification.”

Not all relevant testing was was being performed

The WMSC also highlighted another area of concern about testing that wasn’t being performed, and other tests which were listed as “approved to be bypassed.” Two tests in particular, relating to the power and signaling train systems (“power frequency track circuit tests” and “open-door spillover tests”) were not being performed in October and November of 2020, which WMSC says was during the time that Metro was preparing to re-activate ADO.

Test failures at station platforms could indicate where there could be incidents in which doors open either on the wrong sides of trains, or opening when trains aren’t fully berthed at the platform.

Other tests not always being performed but bypassed based “solely on their own judgement” were interlocking inspection tests, train control room inspection tsts, ground fault testing, and switch obstruction tests.

What’s next?

It’s unclear with the information available what’s next for ADO, and what this means for the background activities that have been in the works to try and restore Automatic Train Operation. Turning ADO on across the rest of the Metrorail system, which was originally scheduled for early April, was put on hold, and is now likely even further delayed.

ATO testing, operator training, and wayside equipment adjustments, have also been done without following the proper safety certification process, according to WMSC, which at best likely means that process is paused as well. Metro had been targeting a re-launch of ATO as early as 2022, but that is now very likely in doubt.