4 ms·

[citation needed] I'm not seeing anything about this; everything online says standard trains are still an active locomotive and passive cars.

• ChuckMcM 12y ago
  http://en.wikipedia.org/wiki/Multiple-unit_train_control http://en.wikipedia.org/wiki/Multiple-unit_train_control covers the gist of it. One of the challenges of long trains is that you can't easily start them on a curve. As the front of the train is pulled it wants to 'straighten out' and that would pull mid-train cars off the track, Such trains if they don't use MU put locomotives both in the back and the front (and some times mid-train). The advantage of standardized MU is that your engine is simply a control center (especially if you're using power from overhead catenary wires) and any train of any length can "work" because the traction motors in every car are sufficient to push that car with some flexibility (some can push up to two additional 'dead load' cars.) But as others have pointed out, in the US the tracks are primarily straight, the existing traction motors in diesels system works well enough, and there is little incentive to change. That said, one of the options on the table for electrified CalTrain is MU equipped cars so that train sizes can be varied depending on commute load.
  • cbr 12y ago
    MU allows you to have multiple locomotives controlled together, but individual train cars still generally don't have traction motors. There are specialized traincars that have motors but not generators [1] but I don't think these were what foobarian was referring to. [1] http://en.wikipedia.org/wiki/Slug_(railroad) http://en.wikipedia.org/wiki/Slug_(railroad)
  • ubernostrum 12y ago
    The exact claim being responded to was "modern trains have electric motors on each car".