4 ms·

Huh, the MBTA Green Line in Boston has a couple of sharp turns where it makes unbearable high pitched shrieks too, I wonder if it's also using flat tracks...

• IIAOPSW 4y ago
  Probably the flange scratching the side of the rail.
• iggldiggl 4y ago
  The Green Line still is very much a streetcar at heart, and at those kinds of tight radii no amount of rail inclination (that is no reasonable amount of inclination, after all the whole shebang still needs to work on tangent track, too) will be able to compensate for the difference between outer and inner wheels. The best you can try is add some sort of lubrication, but even that won't fully quieten it down, since you can only lubricate the flanges, but not the running surface for hopefully obvious reasons.
  • ant6n 4y ago
    U can individually suspend the wheels, rather than using a fixed axle. Some low floor trams (streetcars) have those, because it allows passenger areas where otherwise the axle would be.
    • iggldiggl 4y ago
      Yes, but then you're losing the self-steering, which isn't ideal, either. For low floor vehicles you take that compromise (except possibly at the vehicle ends if you don't need fully 100 % low floor), but otherwise it looks like fixed axles still are the preferred solution.