4 ms·

Why does it take 8-12 hours to shut down? Serious question, not being snarky, just... the "dumb guy confidence" thing is to say "just stop the trains".

by rtpg 5y ago

kd5bjo 5y ago
As the trains move through the tunnels, they move a large quantity of air with them. I wouldn’t be surprised if that air movement was a critical piece of the ventilation/heat dissipation strategy for some equipment located down there.
epc 5y ago
I don’t have a ready article to link to but there might be some from when Sandy hit in 2012. Basically: there isn’t enough safe space to park all of the trains when they know the system might flood. They could just stop trains where they are but then they have to get people to/from the trains and there’s a risk that any given train may develop a fault and block the line it’s on. It’d be better if they could just park in the train yards but several are at sea level.
epc 5y ago
This quote is from a WSJ article “New York City Subways to Shut Down as Sandy Nears“ on 28 October 2012: https://www.wsj.com/articles/SB10001424052970204840504578084582421401190 https://www.wsj.com/articles/SB10001424052970204840504578084... “The shutdown is a matter of complexity and risk-management for the MTA. A key objective for the agency on Sunday: moving thousands of buses and subway cars out of low-lying parking lots and yards that could be hit by a storm surge, including the 148th Street Lenox Terminal yard in Harlem and the Coney Island yard in southern Brooklyn, the largest rapid-transit yard in the U.S. On Sunday, MTA workers were moving trains from low-lying areas to safe underground storage spots, including express tracks on the more than 700-mile subway system. Workers also secured vulnerable electronic equipment that could be susceptible to the corrosive saltwater of a storm surge.”

4 ms·

Why does it take 8-12 hours to shut down? Serious question, not being snarky, just... the "dumb guy confidence" thing is to say "just stop the trains".

by rtpg 5y ago

Why does it take 8-12 hours to shut down? Serious question, not being snarky, just... the "dumb guy confidence" thing is to say "just stop the trains".

kd5bjo 5y ago
As the trains move through the tunnels, they move a large quantity of air with them. I wouldn’t be surprised if that air movement was a critical piece of the ventilation/heat dissipation strategy for some equipment located down there.
epc 5y ago
I don’t have a ready article to link to but there might be some from when Sandy hit in 2012. Basically: there isn’t enough safe space to park all of the trains when they know the system might flood. They could just stop trains where they are but then they have to get people to/from the trains and there’s a risk that any given train may develop a fault and block the line it’s on. It’d be better if they could just park in the train yards but several are at sea level.
epc 5y ago
This quote is from a WSJ article “New York City Subways to Shut Down as Sandy Nears“ on 28 October 2012: https://www.wsj.com/articles/SB10001424052970204840504578084582421401190 https://www.wsj.com/articles/SB10001424052970204840504578084... “The shutdown is a matter of complexity and risk-management for the MTA. A key objective for the agency on Sunday: moving thousands of buses and subway cars out of low-lying parking lots and yards that could be hit by a storm surge, including the 148th Street Lenox Terminal yard in Harlem and the Coney Island yard in southern Brooklyn, the largest rapid-transit yard in the U.S. On Sunday, MTA workers were moving trains from low-lying areas to safe underground storage spots, including express tracks on the more than 700-mile subway system. Workers also secured vulnerable electronic equipment that could be susceptible to the corrosive saltwater of a storm surge.”