what's a little ice to the mbta?

[cgull_]

a big problem, of course.

I worked, umm, kind of late, and took a 12:30a Red Line train home.  All was normal until it started moving up the Longfellow Bridge out of Charles/MGH, at which point it stopped moving, at least quickly

Comments

[jbsegal]

Having commuted that train/bridge for 3 years, I'd have to guess that it wasn't just the ice. That never happened to me.

[r_ness]

Wikipedia's List of current systems for electric rail traction says that the MBTA Red Line uses "Top contact" "600 V DC conductor" third rail.

On the same page they note "top contact: oldest, least safe, affected by ice, snow and leaves".

As a side note they list the LIRR as "Top contact" as well, "750 V DC conductor" third rail. Metro-North is listed as "Bottom contact", "750 V DC conductor" third rail, except for the New Haven Line from Pelham to New Haven, which is 12.5 kV, 60 Hz AC overhead line.

They're doing quite a lot of work on the saltshaker bridge, so that combined with the weather may have something to do with the problem. The Red Line is running very slowly over that bridge at the best of times right now.

I took bedfull_o_books to the commuter rail station this morning. MBTA commuter rail is powered by diesel locomotives.

[chocorua]

Underrunning vs. overrunning 3rd rail makes some difference, but the guards used around NYC are mostly there to keep conductive things (both biological & metallic) from making BIG SPARKS. The Orange Line uses 3rd rail heaters - if you look carefully you'll see little red wires coming up from the ballast at the ends of segments. The Blue Line was built with overhead wire above ground to avoid icing problems along the ocean.

Since the 3rd rail heaters were introduced at the T in 1976, it puzzles me why they haven't been installed on the Longfellow Bridge. Or perhaps they were (probably by Dukakis's T), but broke and haven't been fixed. That's more in line with my expectations of the King/Weld/Cellucci/Romney T currently in place.

[chocorua]

I had forgotten about the distinction between NYC's bottom-contact and Boston's top-contact system. Silly me

[cgull_]

"Anonymous" is me, of course.