"only two of the nation’s eighteen state or local railways, Metro-North and the Long Island Rail Road, operate on a third-rail system powered by overhead lines"
For anybody else who was confused by this: the author is (I think) trying to say that Metro-North has some lines equipped with both third rail and overhead wires. Although the accident occurred because of a crash at a level crossing, and had nothing to do with electrification per se.
It did relate to electrification. Metro-North uses a third rail system where the pickup runs on the underside of the third rail, rather than the top. That style of third rail isn't as solidly mounted as ones where the pickup runs on top. In this accident, the third rail broke loose and penetrated the first car of the train, with the power still on.
There's a solution available to prevent railroad crossing accidents, but it requires blocking the highway for much longer.[1] This is a fully interlocked grade crossing. There are gates on both sides of the tracks, vehicle detectors for cars on the tracks, and interlocking with the railroad signals. As a train approaches, first the bells and lights come on. Then the entrance side gates go down. The control system checks that there are no vehicles on the crossing; there are traffic detectors and radars for this. Only then do the exit side gates go down. When all gates are fully down, and the crossing is clear of vehicles, the train gets a clear signal. If there's an obstruction or a damaged gate, the train will slow and stop if necessary.
This requires that the gates go down about a minute before the train arrives, because the stopping distance for trains is so large. Drivers hate that. Railroads aren't too happy with it either, because they're going to have to stop trains when someone is still on the crossing a minute before the train gets there. Current FRA rules are that such a setup will be required for grade crossings with trains operating above 110 MPH. Only the Northeast Corridor has such speeds.
There's been one accident at the US at a fully interlocked gate. A car went through a lowered gate into the path of an Acela high speed train.[2] Barrier gates capable of stopping a truck are being considered.
Metro-North's signaling equipment is a nightmare. There was a scheduled upgrade that was supposed to have been in play by January 1st of this year, and the project is still not yet done. Proper monitoring of crossing combined with automatic breaking could have prevented this accident. But Metro-North has neither.
Our transportation infrastructure is being pushed to its limits. If you are a a business owner, please let employees telecommute. I know it's difficult to transition from working in an office to having a fully or partially remote workforce. But the cost savings, benefits to the environment, and impact on employee's morale are worth it. Plus, less chance of dying in a traffic accident.
[+] [-] jpatokal|11 years ago|reply
For anybody else who was confused by this: the author is (I think) trying to say that Metro-North has some lines equipped with both third rail and overhead wires. Although the accident occurred because of a crash at a level crossing, and had nothing to do with electrification per se.
https://en.wikipedia.org/wiki/Metro-North_Railroad#Electric_...
[+] [-] Animats|11 years ago|reply
There's a solution available to prevent railroad crossing accidents, but it requires blocking the highway for much longer.[1] This is a fully interlocked grade crossing. There are gates on both sides of the tracks, vehicle detectors for cars on the tracks, and interlocking with the railroad signals. As a train approaches, first the bells and lights come on. Then the entrance side gates go down. The control system checks that there are no vehicles on the crossing; there are traffic detectors and radars for this. Only then do the exit side gates go down. When all gates are fully down, and the crossing is clear of vehicles, the train gets a clear signal. If there's an obstruction or a damaged gate, the train will slow and stop if necessary.
This requires that the gates go down about a minute before the train arrives, because the stopping distance for trains is so large. Drivers hate that. Railroads aren't too happy with it either, because they're going to have to stop trains when someone is still on the crossing a minute before the train gets there. Current FRA rules are that such a setup will be required for grade crossings with trains operating above 110 MPH. Only the Northeast Corridor has such speeds.
There's been one accident at the US at a fully interlocked gate. A car went through a lowered gate into the path of an Acela high speed train.[2] Barrier gates capable of stopping a truck are being considered.
[1] http://www.ansaldo-sts.com/sites/ansaldosts.message-asp.com/...
[2] [http://www.nytimes.com/2005/09/30/nyregion/30acela.html]
[+] [-] cthulhuology|11 years ago|reply
[+] [-] normloman|11 years ago|reply