Fastest Speed and Block Signaling

[Rutgers Tube]

Two questions:

 

1. What segment of track in the transit system permits the fastest speed? I had previously heard that express trains between 125th Street and 59th Street-Columbus Circle can really open up through that span. Is that true?

 

2. Is there any part of revenue operations that does NOT use automatic block signaling?

[Alex L.]

Two questions:

 

1. What segment of track in the transit system permits the fastest speed? I had previously heard that express trains between 125th Street and 59th Street-Columbus Circle can really open up through that span. Is that true?

 

2. Is there any part of revenue operations that does NOT use automatic block signaling?

 

1 - Currently, the fastest speeds are reached between Queensboro Plaza and Lexington Ave on the N/W.

 

2 - The line when operating under CBTC Rules.

[SubwayGuy]

Yup the speed restriction thru the 60th St tube is 50 MPH

[Maserati7200]

Yup the speed restriction thru the 60th St tube is 50 MPH

 

Then why have I seen R160's go up to 57 and R68's go up to 58 MPH in the 60th street tube without the timer going off?

[Y2Julio]

 

Then why have I seen R160's go up to 57 and R68's go up to 58 MPH in the 60th street tube without the timer going off?

GT signals won't clear if the train is going faster than the speed posted on the GT sign.

[Maserati7200]

Yeah I know. But I'm not estimating, I saw inside the crack R160 door cab with my own eyes in the 60th street tube of it going 57 MPH. I'm not lying, I have no reason to. If the GT is 50, why do R160's generally hit in the mid-high 50's in that tunnel without the timer stopping them? Here is a video by FanRailer of an R68A hitting 58 MPH:

http://www.youtube.com/watch?v=ZcPDbC_tO2Q&feature=channel_page

[metsfan]

The 8th ave express gets up to about 45 i'd estimate.

 

- A

[Rapid Transit TO]

If the GT is 50, why do R160's generally hit in the mid-high 50's in that tunnel without the timer stopping them?

 

Timers are placed around the system to slow trains/operators down. However, all signals are NOT on time control. Once a timer signal clears, the train operator will decide how to proceed based on the next signal.

[SubwayGuy]

Yeah I know. But I'm not estimating, I saw inside the crack R160 door cab with my own eyes in the 60th street tube of it going 57 MPH. I'm not lying, I have no reason to. If the GT is 50, why do R160's generally hit in the mid-high 50's in that tunnel without the timer stopping them? Here is a video by FanRailer of an R68A hitting 58 MPH:

http://www.youtube.com/watch?v=ZcPDbC_tO2Q&feature=channel_page

 

Couple of reasons...without being there couldn't tell you exactly why but here are some things that would come into play:

 

1) Timers don't stop you for exceeding the speed limit. They stop you if your average speed is greater than the posted speed limit for the given timed section. In other words, if you pass a signal that starts a timer further down and it's let's say a GT 10, you can stop the train, wait, count to 10, and wrap it up, get to 20 mph and not get tripped unless the signal is still red when you pass it (which would mean your avg speed was >10). Only wheel detectors will stop a train solely for exceeding the speed limit.

 

2) the 60th st tube timers are TWO shot timers, which means if a T/O is doing the speed limit, the signal immediately in front of him should clear from yellow to green as he gets there. ONE shot timers clear from red to green if he approaches at the right speed. But since two shot timers clear from yellow, if he misses, he won't get tripped and can still slow down before the next one (the red). The red will clear to yellow as the yellow would have cleared to green. This builds in a "cushion" for the T/O of one signal block length to miss the timer by but still not get tripped. Of course if a TSS sees him regularly doing this...

 

3) the train took a while to get up to speed, meaning time signals were counting down while he was still accelerating and averaging well under 50mph

 

4) the T/O may have been a veteran and known the way those timers clear and how to operate through them quickly without gettinng tripped.

[R44 5278]

I've seen R44s hit 50 along Fulton express multiple times. Speaking of Central Park West, if there's no congestion then trains can hit 55 without any problems.

[Maserati7200]

Couple of reasons...without being there couldn't tell you exactly why but here are some things that would come into play:

 

1) Timers don't stop you for exceeding the speed limit. They stop you if your average speed is greater than the posted speed limit for the given timed section. In other words, if you pass a signal that starts a timer further down and it's let's say a GT 10, you can stop the train, wait, count to 10, and wrap it up, get to 20 mph and not get tripped unless the signal is still red when you pass it (which would mean your avg speed was >10). Only wheel detectors will stop a train solely for exceeding the speed limit.

 

2) the 60th st tube timers are TWO shot timers, which means if a T/O is doing the speed limit, the signal immediately in front of him should clear from yellow to green as he gets there. ONE shot timers clear from red to green if he approaches at the right speed. But since two shot timers clear from yellow, if he misses, he won't get tripped and can still slow down before the next one (the red). The red will clear to yellow as the yellow would have cleared to green. This builds in a "cushion" for the T/O of one signal block length to miss the timer by but still not get tripped. Of course if a TSS sees him regularly doing this...

 

3) the train took a while to get up to speed, meaning time signals were counting down while he was still accelerating and averaging well under 50mph

 

4) the T/O may have been a veteran and known the way those timers clear and how to operate through them quickly without gettinng tripped.

 

Oh, I get it! Thanks

[MTR Admiralty]

I've seen R44s hit 50 along Fulton express multiple times. Speaking of Central Park West, if there's no congestion then trains can hit 55 without any problems.

It does seem as though a train along the CPW Express will break 50. However, I must check the speed reader first before making a final conclusion.

[Maserati7200]

I've been on R32's on CPW Express and the fastest I've seen them go was about 35. That may be because of congestion, but its not exactly mind blowingly fast.

[MTR Admiralty]

I've been on R32's on CPW Express and the fastest I've seen them go was about 35. That may be because of congestion, but its not exactly mind blowingly fast.

I'm convinced that it could blow at least 35. That is provided there are no rubies in front.

[R62A 1991]

CPW has the potential to go seriously fast, however, the problem, at least downtown, is that there are no timers on the uphill (slightly) section, then when you get to 86th St, BAM, a GT/45 hits you, and most T/Os slow down too much I think, and it's timered all the way to 59th St, getting slower and slower after 72nd St. Uptown is a different story, but it is also timered very early, I think right as you hit 96th St, but it stops after 103rd St until you get to the curve into 125th St.

[MTR Admiralty]

Uptown trains slow before 103, due to the grade change at 103 and 110. Trains slow again at 116th.