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Anyone have a general speed for the Bloor-Danforth Subway between broadview and woodbine.
 
Think that closing parts of the subway for a weekend is a pain. How about for an entire month? That's happening in Boston, with North America's oldest subway.

The Green Line Is Taking A Summer Break
The C and E branches will each close for a month this summer to accelerate track work and intersection upgrades. Will MassDOT give buses the space they need to pick up the slack?

From link.

The MBTA today announced plans to close two branches of the Green Line for a month at a time this summer in order to replace tracks and upgrade intersections as part of its “Green Line Transformation” projects.

In order to expedite track replacements and intersection upgrades, the T plans to close the Green Line’s C branch – which runs along Beacon Street through Brookline – during the entire month of July, and the E branch – which runs along Huntington Avenue to the Longwood Medical Area – for most of August.

In an effort to get deferred maintenance work done more quickly, the T began closing segments of the Orange Line for entire weekends last fall, which allowed workers more extended and productive blocks of time in which they could set up workzones, replace tracks, and upgrade stations.

The T claims that by shutting down each of these Green Line branches for a solid month, they can complete work that would have otherwise taken two years to finish.

In a separate project, the MBTA recently announced that the north end of the Green Line, from Lechmere to North Station, would also be shut down for nearly a year starting in May as part of the Green Line Extension project.

On Wednesday, seven lawmakers representing nearby districts delivered a letter to MassDOT Secretary Stephanie Pollack to request dedicated bus lanes on the Charles River Dam road in order to facilitate replacement bus service during the closure.

The project “will necessitate the diversion of some 14,000 individual trips from the Green Line to replacement shuttle buses every weekday,” according to the letter co-signed by Rep. Mike Connolly, Rep. Jay Livingstone, Rep. Christine Barber, Rep. Denise Provost, Sen. Patricia Jehlen, Sen. Joe Boncore, and Sen. Sal Didomenico. “For the sake of fairness, equity, and efficiency, every effort should be made to prioritize these transit riders.”

The T also plans to numerous weekend closures on several other rail lines in the coming year. A full list of disruptions has been posted at www.mbta.com/projects/building-better-t-2020.

The good news for them, they have alternate routes available.
 
Top speeds.
Practically, I'd assume the top speed is about 65 km/h (given the stretch between Woodbine and Coxwell). Generally, trains probably won't exceed 60 km/h on these short stretches.

Hypothetically, you could probably go 70 miles per hour or more if you wanted to through most sections (not including crossovers, switches, and tail tracks, and assuming TTC trains were built up to spec for that), it's a fairly straight section of track. You just can't stop or slow down for any reason.
 
Practically, I'd assume the top speed is about 65 km/h (given the stretch between Woodbine and Coxwell). Generally, trains probably won't exceed 60 km/h on these short stretches.

Hypothetically, you could probably go 70 miles per hour or more if you wanted to through most sections (not including crossovers, switches, and tail tracks, and assuming TTC trains were built up to spec for that), it's a fairly straight section of track. You just can't stop or slow down for any reason.


The T1 (not sure about the TR) trains have a high rate switch in the cab to allow them go around 70 kph I believe but Dan would know more about that than I would.

With the way the system is designed I would not go over 50 kph. It would make stopping at stations difficult and if you have to stop in a hurry it could be dangerous.

I had a train stop dead to avoid a priority one at Bathurst and watched people go flying when the train went into emergency. That was at a normal speed.. I can only imagine how bad it would have been at a high rate of speed.
 
Back in the days without SCS, trains go reach 85-90 km/h eastbound heading into Old Mill. Most of the old Toronto stretch stations aren't spaced wide enough to allow over 50km/h. With wider station spacing, the Crosstown would likely see a much faster top speed around 70-80 km/h.

The T1 (not sure about the TR) trains have a high rate switch in the cab to allow them go around 70 kph I believe but Dan would know more about that than I would.

With the way the system is designed I would not go over 50 kph. It would make stopping at stations difficult and if you have to stop in a hurry it could be dangerous.

I had a train stop dead to avoid a priority one at Bathurst and watched people go flying when the train went into emergency. That was at a normal speed.. I can only imagine how bad it would have been at a high rate of speed.

High rate isn't about top speed but acceleration. One would feel high rate like a fast vs slow elevator. However one wouldn't feel top speed of 50 or 200km/h if it accelerated slowly. The only feedback would be sound from the tracks and tunnel.

It doesn't matter what speed the trains are going in the tunnel. They'll have to apply the brakes accordingly so they are entering slower than a certain speed to be able to stop by the end of the platform.
 
The trains are set up so that they have the power cut-out at 80km/h, and a penalty brake application at 88km/h. On the older equipment especially though, those numbers were a bit loose, and it was well known that certain pieces of equipment were capable of a bit more or less than that. But with the newer equipment, those numbers are pretty firm.

Yes, there is also a high-rate mode that all equipment since the M-class cars have had which will increase the horsepower put out by the traction motors and increase the amount of dynamic braking that they are capable of, but that as a rule hasn't been used since the early 1980s, IIRC. And Steve is correct in that it primarily affects acceleration (and deceleration).

The speed that can be attained is a function of a number of different things. But in the tunnels, the limiting factor is one of two things:the aerodynamic effect of the tunnel itself (frequently referred to as the "piston effect"); and the length between stations, or more precisely in most cases, the lack thereof. Especially on the B-D, there are very seldom any locations where the train is capable of achieving a "balancing speed" - that is, the point at which the power of the traction motors equal to the many varied drag sources on the train, and thus is able to cruise at a constant speed.

Specifically on the section between Danforth and Broadview, the stretch between each station is quite short and so in almost every section there the trains are still accelerating upon arriving at the following station. You can see this by the fact that the first brake markers are almost always located under the platforms, rather than in the tunnel before the station.

There are two places where the trains are capable of higher-than-normal speeds on that stretch, however. The first is westbound from Woodbine to Coxwell - the trains get a bit of a boost as they leave Woodbine as there is a downhill grade immediately west of the platforms. The trains will reach a peak speed about two-thirds of the way to Coxwell before the aerodynamic drag overtakes the forces of gravity and the traction motors, but even so the first braking marker is located about 30 feet east of the platform at Coxwell. The other location is between Donlands and Greenwood, and in both directions. The affect on the trains is very different, however - eastbound the trains accelerate very quickly due to the downhill grade to the Greenwood Yard accesses, but then loose a lot of speed as they climb towards Greenwood. Westbound trains accelerate at a lower rate as they have to climb, but then pick up speed on the downhill into Donlands.

Dan
 
As a side note to current discussions of speed, when I was a kid, TTC operators often left the train cab door open for young rail fans.

I remember being on what I think was the fastest run I've ever been on, NB on Yonge, on the approach to York Mills (down a very big hill).

The train definitely broke 90km/ph, briefly.

I remember the operator having fun, until he overshot the platform by several meters, with the first and second doors of the 1st car in the tunnel beyond the platform.

It wasn't too long after that the TTC changed the signals on that approach (previously all could go solid green), and coded them w/the white light below, and defaulting to reds and yellows with speed limit signs posted in the tunnel.

Such kills joys! LOL
 
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As a side note to current discussions of speed, when I was a kid, TTC operators often left the train cab door open for young rail fans.

I remember being on what I think was the fastest run I've ever been on, NB on Yonge, on the approach to York Mills (down a very big hill).

The train definitely broke 90km/ph, briefly.

I remember the operator having fun, until he overshot the platform by several meters, with the first and second doors of the 1st car in the tunnel beyond the platform.

It wasn't too long after that the TTC changed the signals on that approach (previously all could go solid green), and coded them w/the white light below, and defaulting to reds and yellows with speed limit signs posted in the tunnel.

Such kills joys! LOL

I would very much be interested in drag racing subway cars. Just clear all the signals and put the proverbial peddle to the floor.

First one from Vaughan to Finch without stopping wins an all expenses paid vacation.
 
I would very much be interested in drag racing subway cars. Just clear all the signals and put the proverbial peddle to the floor.

First one from Vaughan to Finch without stopping wins an all expenses paid vacation.

Who can derail first? ?

I'd hate to pay the insurance tab on that one.
 

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