nomis wrote:All MBTA rail services will be suspended at 7:00 p.m. This means no Subway, Trolleys or Commuter Rail trains will depart Boston after 7:00 p.m.
All MBTA rail services will be suspended at 7:00 p.m. This means no subway, trolleys or Commuter Rail trains will depart Boston after 7:00 p.m. Limited MBTA bus service will continue until the end of regular service hours, but customers are advised that connections to subway and Commuter Rail lines will not be available.
Last Updated: 2/9/2015 4:01:07 PM
Latest word is no rail service tomorrow - all day!
If you look carefully at the third rail, you will see that the standard third rail on the Orange line is 85 pound ASCE T-rail with an aluminum conductor bonded to the sides. The contact surface is about two inches wide.
Prior to 1971, the Red Line used a similar rail section, without the aluminum conductor. When the South Shore Extension was opened, it had a new style of third rail, with a squat cross section and a wider contact surface. The new rail was welded into quarter mile sections. As far as power distribution was concerned, it was a success. However, when passing trains brushed snow off the rail, it partially melted and froze, leaving a patch of ice, an electrical insulator. This was corrected by adding heaters at intervals, but you can't heat every inch of third rail. If a six car train is running with two unpowered cars (common), and they stop on the heated spots, you have a dead train. Dead car roulette? Until 1980, this was confined to the extension, but starting in 1980, reconstructed sections got the new style of third rail, including JFK to Ashmont and the Longfellow Bridge. As a result, powerless trains became more common. Expansion of ATO made random stops more common, lowering the odds on a dead train. The replacement of ties on the South Shore Line about 10 years ago was an ideal opportunity to replace the third rail with the more reliable standard variety, but the troublesome variety was retained. The standard variety did appear in a few spots like Park Street Station, safely underground. The rail was responsible for today's problems. Scrapers will work on the narrower standard rail but not on the wider flatter surface. Gravity shoes, used in Chicago on uncovered third rail, may be a cheaper solution, but require new hardware on every car.
Something has to be done!
Gerry. STM/BSRA
The next stop is Washington. Change for Forest Hills Trains on the Winter St. Platform, and Everett Trains on the Summer St. Platform. This is an Ashmont train, change for Braintree at Columbia.