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Washington DC To Return To Automatic Metro Trains
Bruce66423 (1678196) writes with news of interest to anyone with reason to ride mass transit in the U.S., specifically on the D.C. Metro system: After a crash some five years ago, automatic operation was abandoned. Now however replacement of 'faulty' modules means that moving the whole system on to automatic operation can happen. One quote is depressing: "And because trains regularly lurch to a halt a few feet short of where they should be at platforms, Metrorail riders have grown accustomed to hearing an announcement while they're waiting to board: 'Stand clear. Train moving forward.'" That never happens on the London underground with human operators? What's wrong with American drivers?
For example the central line has been automated since the 90s. Drivers there just to go on strike
The Red Line crash was not computer-related. The signalling system for the Washington Metro is a classic electromechanical relay-based system. Just like the New York subways. The Red Line crash was caused by a failure of a track circuit for detecting trains, trackside equipment using an audio-frequency signal sent through the rails and shorted to the other rail by the train's wheels. All those components are pre-computer technology.
As with most railway systems, manual driving isn't enough to prevent collisions, because stopping distances are often longer than visual distances. That was the case here.
The Washington Metro had been sloppy about maintenance of trackside equipment. They do have a central computer system, and it logs what the relay-based signal systems are doing, although it can't override them. They had logs of previous failures, and should have fixed the problem.
First, as of 2010, DC was about 50% Black, 39% White, plus everybody else. Source: http://en.wikipedia.org/wiki/D.... As a (White) DC resident who moved back here a couple of years ago, one of the things I enjoy about the Metro is the casual, random, cheerful conversations I have with my fellow riders who happen to be Black. Second, I live in DC and ride Metro regularly. Occasionally there are annoying people (often Black), but very rarely threatening ones. Cell phone theft on the Metro is a danger here, like most places (and police don't seem to care anywhere). Third, Metro needs to better enforce its rules against food and drink (and smoking) in the system. In effect, Metro no longer enforces that rule so the cars can be a mess. I encountered a White guy smoking on a platform earlier this year and asked him to put it out. He blew me off, quite obnoxiously.
Hence, the acceleration and braking systems were optimized for automatic operation (as opposed to manual operation) and it is difficult for a human driver to control the train's movements precisely and smoothly.
I have a perspective on this that most probably don't, as I was a monorail driver at Disney World for a number of years. Contrary to what some might imagine, the current Bombardier Mark VI trains there are not attractions but are in fact full-up transit vehicles, and Bombardier continues to sell them as such (although with different bodies and newer electronics). If D.C.'s trains handle anything like ours did, I can understand why some of the drivers short-stop or otherwise have problems.
Our Mark VI trains were originally designed to accommodate automation as well, but I don't think this in itself really is a factor. More importantly, each train had its own "personality" and handled differently, and all of them would take between one and two seconds to respond after an input was commanded except for E-stops, which instantly opened the relay contactors and applied air to the friction brakes. One train might be ultra-responsive (relatively) to the throttle and have really tight brakes, which made it easy to drive and predict stopping distances with great accuracy. Others would act like your control inputs were more of a suggestion than a command, necessitating that you be looking a little ahead of where you actually wanted to be in order to stop where you were supposed to. We had some drivers that had difficulty dealing with that, and would often blow their stops by a couple of feet or so on a train with loose brakes, or would stop short if they were in a tighter train that didn't require so much anticipation of its behavior. I don't think I ever had a short stop, but did have trains "slide" on me a few times and missed the stop by just enough to have to back up a couple of inches to get lined up with the gates.
I would imagine transit trains everywhere exhibit similar unique peculiarities, and the only consistent way to deal with it is for the driver to be ultra-conservative, which can lead to the occasional short stop. It's not so much a problem for an automation system that can directly respond in milliseconds and isn't being moved between trains with wildly varying performance characteristics.
Please stand clear of the doors, por favor mantenganse alejado de las puertas
None of the Underground lines are driverless. The ones you list are GoA level 2 (i.e., opening/closing doors, starting the train, and emergencies are handled by the driver). Go look in the cab of any of them, they all have drivers!
Even the DLR is a GoA level 3 system, as the "attendant" handles door closing and emergency driving of the system.
The only GoA level 4 systems (which are truly driverless and can operate without any trained staff onboard) in the UK are the people movers at Heathrow T5, Gatwick, and Stansted.