An Interesting Sign on the Washington DC Metro

I was lucky enough to attend Discon III, the 79th World Science Fiction Convention in December 2021. This was my 5th World SF Convention, and I was quite excited to be going. Although there were risks with the omicron surge just hitting, I was confident that Discon III had done everything possible to minimize risk. I had been vaccinated and boosted, and I was grateful to connect with and spend time with my people.

I thought it was crazy to rent a car for this convention when I was going to spend almost all my time at the convention. I love taking transit in a city that has a real transit system, and I was very happy to take Metro back and forth between Ronald Reagan International Airport and the convention hotel out near the DC zoo.

Metro is a great transit system; my biggest challenge was figuring out the fares correctly and getting my fare card appropriately charged. I screwed that up twice, but this was a minor issue.

When I was flying out after the convention, I saw this sign at the Ronald Reagan International Airport as I exited the platform. It was clearly aimed at the Metro train staff, but I had no idea what the sign meant.

People that know me well know that I am a very curious (water resources) civil engineer that likes to figure things out and understand how things work.

I had a lot of time available waiting for a 3 PM flight, as I had reached the airport probably at 11 am. Luckily I had an internet connection generally. I looked into this and discovered more than I expected.

This type of sign was an indication to me that the Metro trains are on manual operation, with an operator for each one. I know that both system/automatic operation and manual operation are possible for transit systems, although I’m not enough of an insider to know how common manual operation is.

Metro is clearly telling the train operators that there is a location ahead with a history or risk of “overrun”. A bit of research and investigation had told me that “overrun” is where a train is more likely to violate system limitations on speed, adjacency to another train, work crew or the like, cause system damage, derail, or hit another train. While the repercussions vary a lot, none of these are good.

2009 crash photo by NTSB

There was a severe 2009 crash with 8 deaths and 80 injuries on the Metro which caused them to take the system off Automatic Train Operation (ATO) (AKA Automatic Train Control or ATC) and go to full manual, operator control. See info at Wikipedia. Looking into the weeds, it had been operating under ATC with operators providing oversight and backup.

Subsequent investigation (see Wikipedia link above) showed that the ATC/ATO did not cause the 2009 crash. However, for probably complex reasons, Metro has been reluctant to return to ATC/ATO.

There has been at least one investigation into Metro train overruns since 2009, with a number of operational/safety improvements recommended to improve safety and reduce/eliminate overruns. Without knowing for sure, I suspect that overruns are a lot more common with manual operations only.

There is a continued effort to return system operation to ATO.

So, a lot to unpack here from one little sign.

I have no regrets I used Metro, but I do hope they get back to ATO/ATC soon, given that a) it was not the cause of the 2009 crash and b) there have clearly been more overruns and either actual or potential threats to employee and public safety and damage on all manual operation.