# Derailment and Crash on Metro north at Bridgeport Ct



## Dutchrailnut (May 17, 2013)

https://pbs.twimg.com/media/BKf_HPxCcAAzV6p.jpg:large


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## Acela150 (May 17, 2013)

Well it appears that M8's are already for scrap!


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## CHamilton (May 17, 2013)

Injuries Reported In 'Major' Train Derailment In Connecticut


Two Metro-North Railroad trains have collided on a stretch of track near Fairfield, Conn., causing a "major derailment" and "preliminary reports of injuries," according to the Metropolitan Transportation Authority.

The Associated Press quotes a police spokesman as saying there are 20 to 25 injuries, but no fatalities in the accident.

According to The Hartford Courant:



"A Metro-North commuter train derailed Friday night and hit a train heading in the opposite direction near the Fairfield-Bridgeport border, and there are preliminary reports of injuries, an MTA official said.
"At about 6:10 p.m. an eastbound train, the 4:41 p.m. train out of New Haven, derailed just east of the Fairfield metro station, said Marjorie Anders, an MTA spokeswoman. It then hit the side of a westbound train on the adjacent track.


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## Ryan (May 17, 2013)

Amtrak just tweeted that service is suspended indefinitely NYP-BOS.


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## AmtrakBlue (May 17, 2013)

Ryan said:


> Amtrak just tweeted that service is suspended indefinitely NYP-BOS.


Also on FB


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## CHamilton (May 17, 2013)

> AMTRAK SERVICE SUSPENDED INDEFINITELY BETWEEN NEW YORK AND BOSTON
> by Amtrak (Notes) on Friday, May 17, 2013 at 5:02pm
> 
> 
> ...


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## WinNix (May 17, 2013)

This is why first responders should be allowed to train (no pun intended) on the new equipment. As a fire fighter in the area, I have gone through the train derailment mass casualty drills/classes. Each one I've attended is done with the older, out of date stock. These new M8s were never part of the drills or classes. I have experience in forcing the doors/windowshatches on the older cars - a lot of good that will do you if I need to pry you out of a new M8.


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## Amtrak 75 (May 17, 2013)

What caused the accident?


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## Dutchrailnut (May 17, 2013)

way to early to tell, I am sure there will be plenty of Expert speculation way before FRA and NTSB give a report.


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## zepherdude (May 17, 2013)

I heard like 25 people were hurt and cars are laying around all over the place. No real details or pictures from anyone. Sounds like a mess.


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## AlanB (May 17, 2013)

zepherdude said:


> I heard like 25 people were hurt and cars are laying around all over the place. No real details or pictures from anyone. Sounds like a mess.


Huh? :unsure:

A picture started off this topic, and it doesn't show any cars laying around all over the place.


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## Amtrak 75 (May 17, 2013)

Any word on service restoration? And what is the damage to the M8's?


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## OlympianHiawatha (May 17, 2013)

_*WNBC*_ New York just gave an update from Penn Station and it is nothing short of a zoo as Amtrak pax try to figure out how to get to Boston and southbound Corridor service is delayed as well. It will be at least Monday and likely longer before the line is reopened.


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## amamba (May 17, 2013)

I hope all of the injured recover quickly. I just saw some footage on the news. Looks like I'm canceling my Sunday points run into Boston.


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## the_traveler (May 17, 2013)

The local news said the area of the derailment (where 1 train derailed and was hit by a train going the opposite way) is a 4 track main line, but 2 tracks were (and are) shut down due to construction. So there is no way for other trains to get past the site!

What I heard is that they _may_ get the tracks reopened by Monday. Meanwhile, all Amtrak service between NYP and BOS (including shuttles to SPG) and the Vermonter (unless at least 1 set was trapped east of Fairfield) is cancelled.


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## RhondaGB (May 18, 2013)

How will the suspension of service between Boston and New York City affect Amtrak train south of New York City?


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## ALC Rail Writer (May 18, 2013)

One of the problems with the Amtrak system seems to be redundancy. Heaven forbid a plane crash on the runway of LaGaurdia, but if it did it wouldn't shut down all traffic North of New York... problems with other railways in Amtrak's most vital corridors can wreak havoc and vice versa..


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## ALC Rail Writer (May 18, 2013)

the_traveler said:


> The local news said the area of the derailment (where 1 train derailed and was hit by a train going the opposite way) is a 4 track main line, but 2 tracks were (and are) shut down due to construction. So there is no way for other trains to get past the site!


I take it that explains the two white stop signs in the OP pic?


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## chakk (May 18, 2013)

zepherdude said:


> I heard like 25 people were hurt and cars are laying around all over the place. No real details or pictures from anyone. Sounds like a mess.


More like 60 injuries.


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## jis (May 18, 2013)

NYP - WAS service is running normally Sat morning so far. I am on 67. 66 was turned to become 67 at New York. The other 66/67 consist is sitting in BOS.

Because it was turned at NYP platform the consist is running backwards. The Cafe has very little food left since it was not restocked in NYP. It will get restocked in WAS. The OBS crew does not know yet whether he is going to be relieved in WAS or is going through to NPN. He started duty from NPN yesterday.


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## Ryan (May 18, 2013)

ALC_Rail_Writer said:


> the_traveler said:
> 
> 
> > The local news said the area of the derailment (where 1 train derailed and was hit by a train going the opposite way) is a 4 track main line, but 2 tracks were (and are) shut down due to construction. So there is no way for other trains to get past the site!
> ...


 Yeah, sounds like it - that confused me at first.



RhondaGB said:


> How will the suspension of service between Boston and New York City affect Amtrak train south of New York City?


It shouldn't, really. Someone mentioned that SB was delayed last night, but there shouldn't really by any issues as long as there is sufficient equipment stranded on this side of the incident.


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## CHamilton (May 18, 2013)

> AMTRAK SERVICE SUSPENDED INDEFINITELY BETWEEN NEW YORK & NEW HAVEN, CONN., LIMITED SERVICE AVAILABLE BETWEEN BOSTON & NEW HAVEN
> 
> by Amtrak (Notes) on Saturday, May 18, 2013 at 6:42am ET
> 
> ...


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## AlanB (May 18, 2013)

Ryan said:


> ALC_Rail_Writer said:
> 
> 
> > the_traveler said:
> ...


Yes, that area is one of the sections where Metro North is currently doing extensive rebuilding work. In addition to installing constant tension catenary, all bridges within the area are being rebuilt. For this reason, even if MN could find enough diesels to deal with the lack of overhead power, they still can't use the other two tracks as trains aren't very good at jumping.

What is interesting is that generally they only work on 1 track at a time, keeping 3 in service. I'm not quite sure why they decided not to do that in this area and instead took 2 tracks out of service. Perhaps there were some complications with one of the bridges or maybe some other reason.


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## the_traveler (May 18, 2013)

CHamilton said:


> > AMTRAK SERVICE SUSPENDED INDEFINITELY BETWEEN NEW YORK & NEW HAVEN, CONN., LIMITED SERVICE AVAILABLE BETWEEN BOSTON & NEW HAVEN
> >
> > by Amtrak (Notes) on Saturday, May 18, 2013 at 6:42am ET
> >
> > ...


While I understand the SPG shuttles use diesels from NHV to SPG, it still doesn't make sense that they would operate, since 95+% of their passengers switch to/from other trains at NHV, and those trains are not operating


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## AlanB (May 18, 2013)

the_traveler said:


> While I understand the SPG shuttles use diesels from NHV to SPG, it still doesn't make sense that they would operate, since 95+% of their passengers switch to/from other trains at NHV, and those trains are not operating


Yes, but there are some who do travel locally. And some may find other ways to bridge the gap.


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## Fishrrman (May 18, 2013)

As to what may have caused the derailment/collision…

I'm a retired engineman (Conrail/MN/Amtrak) -- worked on the New Haven line for 32 years. Retired in early 2012.

The derailment was in the vicinity of the [now-closed] Burr Road tower, under the I-95 overpass. There's a relatively gentle curve at that location. The eastbound train that derailed would have been turning "towards the right".

I belive tracks 2 and 4 there (tracks 1 and 3 are out-of-service for catenary and bridge construnction) had concrete ties installed several years' back.

I'm not sure how many others may have noticed, but concrete ties have significant problems in some locations due to moisture underneath. They literally begin to disintegrate (from the "bottom up") from the constant pounding of trains above. Unlike wooden ties -- which have some resliience and act as a "shock absorber" between the movement of the train above and the ballast below -- a concrete tie cannot absorb the forces from trains passing over them.

The result is that the ties will begin to grind away underneath, and the powdery residue will be visible on the track surface, as if someone had spilled a bag of cement all around the location.

Second factor: The type of insulated rail joints that are now being used to deliniate blocks. These are "pre-assembled" (I think some kind of adhesive is used to further strengthen them), and then spliced in at the required locations. The splices are then "welded in place" with the existing rails.

These insulated joints are very good when new -- almost undectable from the viewpoint of operating over them. But that's _when new_. As they age, they can work their way "loose", and the joint can begin to "fall down".

Now -- combine a location that has one of these aging insulated joints (perhaps on both rails) with concrete ties at a location where there is moisture underneath. Not only do you have the downward and lateral forces exerted by the train above, the point of wear is compounded by the bad joint, continually "pounded down".

At some point, the wear may be enough that something breaks under load.

If it were just "solid rail", a few ties might break. But under a bad joint, the joint itself might break, and now you have broken rail combined with ties that simply crumble under the stress. Thus -- the beginning of the derailment.

The fact that the location involves curvature, might explain why the eastbound on track 4 now fouled track 2 -- at the same moment that a westbound train was passing by.

From what I could see from the pictures available on the net, looks like the eastbound on 4 (that derailed) may have run into trouble just about where the "old limits" of Burr Road once were. The switches and signals are gone now, but the insulated joints still remain (this is where the second block west of CP255 begins).

This is only my guess:
The insulated joints of that location, on concrete ties, had worn down, resulting in heavy pounding of the ties below, which had begun to disintegrate. The forces of the passing train yesterday became "the straw that broke the camel's back" -- the joint broke apart, the train derailed and fouled track 2, after which the westbound struck it.

I could be wrong, but that's how I see it….As to what may have caused the derailment/collision…


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## Dutchrailnut (May 18, 2013)

you guessed wrong on concrete ties, at location it had wooden ties.


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## Dismayed (May 18, 2013)

WOW, it seems to say something about this forum when only Amamba has expressed any concern at all about the fact that at least 70 passengers were injured, FIVE critically. Everyone else seems more worried about the inconveniences in service that has been caused.


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## SarahZ (May 18, 2013)

Dismayed said:


> WOW, it seems to say something about this forum when only Amamba has expressed any concern at all about the fact that at least 70 passengers were injured, FIVE critically. Everyone else seems more worried about the inconveniences in service that has been caused.


Do not judge this forum by a few posts. I am extremely concerned for all involved. I just didn't post as such. I have, however, been keeping tabs on this thread and various news sources.

Also, I saw quite a few posts expressing concern...


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## ALC Rail Writer (May 18, 2013)

Dismayed said:


> WOW, it seems to say something about this forum when only Amamba has expressed any concern at all about the fact that at least 70 passengers were injured, FIVE critically. Everyone else seems more worried about the inconveniences in service that has been caused.


Well all I want to discuss is the technical aspects, I don't see what's wrong with that. That's the beauty of an online forum, you can discuss whatever aspect of a topic you wish. If you want to express sympathy and share those feelings with others, then by all means. I'll pay respect quietly in my heart and use my time here to discuss what matters to me.


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## CHamilton (May 18, 2013)

> UPDATE: AMTRAK SERVICE REMAINS SUSPENDED INDEFINITELY BETWEEN NEW YORK AND NEW HAVEN, CONN
> by Amtrak (Notes) on Saturday, May 18, 2013 at 10:26pm ET
> 
> _Limited service available between Boston and New Haven, Conn._
> ...


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## amamba (May 19, 2013)

I had to call to cancel my points run as it was within 24 hours of my train, and to my surprise, there was barely any hold time. The phone agent was very helpful in cancelling my trip and giving me a full refund.


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## Train2104 (May 19, 2013)

The cars have been removed and the scene will be turned over to MNR tonight so that the complete rebuilding of 2000 feet of track and catenary may begin.

MNR is running a shuttle bus and train system tomorrow, with the railroad open as far east as Westport and as far west as Bridgeport. Amtrak tickets will be cross-honored.


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## George Harris (May 19, 2013)

zepherdude said:


> . . . cars are laying around all over the place.


This is an extremely wild exaggeration. This statement based on aerial shots I have seen, I beleive it was on CNN.


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## leemell (May 19, 2013)

A report this morning said that a rail fractured causing the derailment and sideswipe. The NTSB has removed segment of the rail and sent to a lab for analysis. The report also said that no repairs or construction started and will not until NTSB releases the site from the investigators. The report implied about a week for service restoration.


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## CHamilton (May 19, 2013)

> UPDATE: AMTRAK SERVICE REMAINS SUSPENDED BETWEEN NEW YORK AND NEW HAVEN, CONN.
> 
> by Amtrak (Notes) on Sunday, May 19, 2013 at 6:09pm ET
> 
> ...


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## CHamilton (May 20, 2013)

> Connecticut Train Collision Exposes Cracks in the Northeast Corridor
> 
> 
> Investigators are still poring over Friday’s train derailment and collision in Connecticut. Early reports point to damaged track as the cause of the crash that injured 70 people.
> ...


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## jis (May 20, 2013)

Fishrrman said:


> This is only my guess:
> 
> The insulated joints of that location, on concrete ties, had worn down, resulting in heavy pounding of the ties below, which had begun to disintegrate. The forces of the passing train yesterday became "the straw that broke the camel's back" -- the joint broke apart, the train derailed and fouled track 2, after which the westbound struck it.
> 
> I could be wrong, but that's how I see it….As to what may have caused the derailment/collision…


Your guess may turn out to be more right than you can imagine. Apprently last week those joints were replaced on that track, and apparently the failure is in the vicinity of those joints. 


leemell said:


> A report this morning said that a rail fractured causing the derailment and sideswipe. The NTSB has removed segment of the rail and sent to a lab for analysis. The report also said that no repairs or construction started and will not until NTSB releases the site from the investigators. The report implied about a week for service restoration.


Notwithstanding all that, NTSB released the site yesterday. many of the damaged cars were moved to New Haven yesterday, and work is continuing apace today at the accident site to repair the tracks. Photos of the work site are available on railroad.net Metro North board.Here are some pictures:

http://www.flickr.com/photos/mtaphotos/sets/72157633537080338/with/8755508274/

Presumably the rest of the cars, which appear to be the ones on the train that did not originally derail, but derailed as a result of the crash, and are visible in one of the pictures, will be moved today, or may have already been moved.


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## CHamilton (May 20, 2013)

> UPDATE: AMTRAK SERVICE REMAINS SUSPENDED BETWEEN NEW YORK AND NEW HAVEN, CONN.
> by Amtrak (Notes) on Monday, May 20, 2013 at 4:30pm ET
> 
> 
> ...


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## RRUserious (May 20, 2013)

Just shows AGAIN how the country is paying and will pay for deprioritizing infrastructure. Our paralyzed government will get nothing done. Bridges will continue to fall. And we'll all swallow hard as we wonder what in the infrastructure might fall apart on this trip! We live in a crazy society. Athletes spend 3/4 million on an engagement ring. But repairing a bridge is "oh, can we really afford it?"


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## jis (May 20, 2013)

And you reach this conclusion based on an accident that was most likely caused by the failure of a joint that was installed recently, in an area where two tracks are out of service because the infrastructure is literally being rebuilt ground up? Oooookayyyyy.


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## George Harris (May 20, 2013)

Dutchrailnut said:


> you guessed wrong on concrete ties, at location it had wooden ties.


Look at the series of pictures posted by CHamilton. Both types were in that area. One picture shows a pile of broken concrete ties.


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## MikefromCrete (May 20, 2013)

Looks like it was mostly wooden ties in most of the photos.


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## RRUserious (May 20, 2013)

jis said:


> And you reach this conclusion based on an accident that was most likely cause by the failure of a joint that was installed recently, in an area where two tracks are out of service because the infrastructure is literally being rebuilt ground up? Oooookayyyyy.


And of course they had LOTS of money to insure it was done right? What do you base that on? Lots of crappy stuff built here in America. You know, lowest bid gets the contract?


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## jis (May 20, 2013)

What bid? MNRR maintains its own tracks.

But I see we are into gratuitious baseless America bashing today. So I'm outa here.


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## jis (May 20, 2013)

Metro North and presumably Amtrak service through the derailment area is expected to be restored Wednesday morning.

See http://newyork.cbslocal.com/2013/05/20/extremely-challenging-work-week-begins-for-30k-metro-north-commuters/



> BRIDGEPORT, Conn. (CBSNewYork/AP) – Metro-North officials announced Monday afternoon that normal service on the New Haven line is set to resume for the Wednesday morning commute.
> 
> “We are confident that the reconstruction work, inspection and testing will be completed in time for a normal rush hour on Wednesday,” said Metro-North President Howard Permut. “We are grateful for the tireless work of all departments and employees engaged in this huge task.”
> 
> ...


Also see Metro North's announcement: http://new.mta.info/mta-metro-north-railroad-foresees-full-service-wednesday-morning

and here is what looks like the culprit:


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## Ryan (May 20, 2013)

RRUserious said:


> Just shows AGAIN how the country is paying and will pay for deprioritizing infrastructure. Our paralyzed government will get nothing done. Bridges will continue to fall. And we'll all swallow hard as we wonder what in the infrastructure might fall apart on this trip! We live in a crazy society. Athletes spend 3/4 million on an engagement ring. But repairing a bridge is "oh, can we really afford it?"


Here, have one of these:


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## RRUserious (May 20, 2013)

Makes one wonder about "bullet trains". Gonna need different track technology I think.


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## CHamilton (May 20, 2013)

Ryan, yes, we shouldn't read too much into this one incident. But I don't think it's unreasonable to say that our rail infrastructure is fragile. Out here in the northwest, we've seen lots of issues with mudslides, floods, and capacity constraints that can't easily be resolved, because there are no alternative tracks in operation any more. And I suspect this will be a wake-up call for those politicians and members of the public who thought that the NEC didn't have similar problems (although we knew better).


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## CHamilton (May 20, 2013)

> Full Service to Resume Between Boston & New York on Wednesday
> 
> by Amtrak (Notes) on Monday, May 20, 2013 at 8:03pm ET
> 
> ...


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## Dutchrailnut (May 21, 2013)

George Harris said:


> Dutchrailnut said:
> 
> 
> > you guessed wrong on concrete ties, at location it had wooden ties.
> ...


The track that train 1546 derailed on had wooden ties (track 4)track 2 Has Concrete ties but was damaged by 1546's last 4 cars derailing ito path of train 1581

So again the track involved in derailment had wooden ties.


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## CHamilton (May 21, 2013)

> UPDATE: AMTRAK RESUMES SERVICE BETWEEN NEW YORK AND NEW HAVEN, CONN.
> by Amtrak (Notes) on Tuesday, May 21, 2013 at 12:23pm ET
> 
> 
> ...


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## jis (May 21, 2013)

From Metro North:



> Limited Metro-North Railroad and Amtrak train service will resume this afternoon between New York and New Haven, followed by regular service on Wednesday, MTA Metro-North Railroad, the Connecticut Department of Transportation and Amtrak announced.
> With one of the two damaged tracks rebuilt and returned to service, beginning with the 3:07 p.m. departure from Grand Central Terminal, Metro-North will operate about half of the regular eastbound PM peak service and regular hourly westbound service with the 4:23 PM train from New Haven. Metro-North will continue to operate on a regular schedule between Grand Central and South Norwalk in both directions.
> 
> On Friday, May 17, a Metro-North train derailed in Bridgeport and was struck by another train going in the opposite direction.
> ...


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## afigg (May 21, 2013)

So the New Haven Line is now a 1 track line for 7 miles with 30 mph max speed. "Metro-North expects there will be delays as a result". Can't they simply say that there WILL be delays? When the second track is restored tonight, it will get better, but the On-Time Performance between BOS and NYP is going to take a hit for a while.

I wondered what the status was of the 7 mile segment that has been down to 2 tracks total for several years. Found an April 30, 2013 status update on the CT DOT website. The good news is that it looks that the segment could be back to 4 through tracks by early 2014. With the 4th track added at the New Haven end for the new West Haven train station, Amtrak may finally be able to trim some time off of the schedule for NYP to BOS trains.


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## anir dendroica (May 21, 2013)

Not to be too hard on Amtrak and the NTSB, but a five-day closure seems unnecessarily long for what is arguably the busiest rail line in the US. BNSF usually manages to clean up messes of that magnitude in about 24 hours.


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## leemell (May 21, 2013)

NTSB held repair until their investigation was done. They released the track for repair Monday.


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## jis (May 21, 2013)

anir dendroica said:


> Not to be too hard on Amtrak and the NTSB, but a five-day closure seems unnecessarily long for what is arguably the busiest rail line in the US. BNSF usually manages to clean up messes of that magnitude in about 24 hours.


Amtrak is not involved in the track repair at all, so being hard at all on Amtrak would be misguided in this case.

Of course BNSF does not have to deal with catenary and a sophisticated signaling and ATC system either. It took Metro North less than 48 hours after NTSB released the track to their charge to get the first track up and running.,

How often does BNSF have a mess involving over 70 human injuries BTW?


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## ALC Rail Writer (May 27, 2013)

Ryan said:


> RRUserious said:
> 
> 
> > Just shows AGAIN how the country is paying and will ...
> ...


Office Space, yes!


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## RRUserious (May 30, 2013)

Saw a TV show on the Acela Express. The train seems to have some nice engineering, but I'm wondering about the tracks and the bed on which it runs. Looks pretty old school to me. My impression about train speeds in the US is that they are limited by the poor condition of our track infrastructure. Naturally, I expected a high speed line to have replaced the tracks with state of the art. Is that true? How advanced are the tracks the Acela rides on?


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## George Harris (May 30, 2013)

What I see in the picture is a broken joint bar. Looks like it may have been a temporary joint awaiting a weld, as the bolt nearest the rail end is missing, which means there was probably not a hole through the web. Normally with a temporary joint the end hole is not drilled as it is too close to the weld position. Why it broke I will not guess. There is simply not enough to be seen in the pictures I have seen to make a guess.

People start arm waving and shouting obsolete when they don't know what else to say. For the speed and axle load the track as it was should not be a problem. There is nothing wrong with using wood ties. A good wood tie will last over 30 years. It is much less finicky than a concrete tie about the condition of its support. Whether wood or concrete is as much a matter of economics and opinion as anything. Yes a concrete tie track is a little heavier. However, a wood tie embeds better into the ballast. Look at pictures of the French TGV. The track under it has ties. Concrete ties, yes but then so does most track in Europe due to the cost of timber and that the railroads are political animals. Most of the more recently built Shinkansen track is on concrete slab. One primary advantage of concrete slab track is that it stays where it is put rather than walk around like ballasted track, but either type works fine under the speeds and traffic volumes that exist where this happened.

Yes the track centers are much closer than they would be built today, or any time within the last 75 years or so, but that is the most difficult thing to change, and while may have been a factor in the accident events, it is highly unlikely to be any part of the cause.

I saw a post several back from a retired train service man about problems with the new-fangled insulated joints. I really don't know how to answer it as his statements were somewhat strange. The type of insulated joints used now and for over 30 years are commonly called glued joints. That is, the joint bar - insulation - rail - insulation - joint bar sandwich is epoxy bonded and the bolts are there primarily to squeeze everything together while the glue sets and function as a backup in case of bond failure. Usually these things will last as long as the rail.


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## Ryan (May 30, 2013)

What do you mean by "advanced"? It's steel rails, riding on wood or concrete ties. Not must "state of the art" about it, the technology was perfected 100 years or more ago.


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## jis (May 31, 2013)

Two points ....

1. The track around Bridgeport is not "high speed track" using any reasonable definition of the term. MAS is 70mph there.

2. Track on which MAS is 125mph or higher on the NEC is pretty much state of the art concrete ties on ballast mostly, with wood ties only at a few remaining interlockings which are scheduled to be completely replaced with higher speed moving frog switches on concrete ties in the next two or so years.


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## PRR 60 (May 31, 2013)

jis said:


> Two points ....
> 1. The track around Bridgeport is not "high speed track" using any reasonable definition of the term. MAS is 70mph there.
> 
> 2. Track on which MAS is 125mph or higher on the NEC is pretty much state of the art concrete ties on ballast mostly, with wood ties only at a few remaining interlockings which are scheduled to be completely replaced with higher speed moving frog switches on concrete ties in the next two or so years.


MAS = ????


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## Ryan (May 31, 2013)

Maximum Authorized Speed?


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## George Harris (May 31, 2013)

Ryan said:


> What do you mean by "advanced"? It's steel rails, riding on wood or concrete ties. Not must "state of the art" about it, the technology was perfected 100 years or more ago.


"State of the art" means the current best practice appropriate to the service. How long it has been best practice is not part of it.

Perfected 100 years ago? Let's see: Wood tie size, species limitations, treatment processes and substances have had considerable development over the last 100 years. Concrete ties are considerably stronger than those first introduced into the US nearly 50 years ago. Shapes have also been modified to improve embedment in the ballast. Ballast, changes in rock specifications for materials, gradation, etc. Rail? AREMA has a list of rail sections in use since around 1900. It has over 400 rail section shapes in it. There are even a few missing from the list. And this list is just North America. Go to other parts of the world and there are others. Do you think that the people who work with this stuff don't look over each other's shoulders? Of course thy do. Over the last several years the list of shapes in use in North America has gotten relatively short. There are several things to shape, by the way: Proportion of section, head, that is wheel contact area, head to web, primarily internal stress distribution issue, base shape, etc, then there are metallurgical and hardness issues. There have literally been books written on the subject, although they have not exactly been best sellers. Then there are rail to tie fastener issues, appropriately zero-stress temperature, and more. There have been studies and full scale test installations of various forms of concrete based track, and there are currently several types of concrete base track in widespread use. There is a lot going on in this subject. Just because you do not see it does not mean it is not there. One factor that makes it less obvious is the longevity of most track components. A good wood tie will last over 30 years, concrete ties will/may last longer. the current designs have not been around near that long. Depending upon traffic and curvature, rail can go up to 100 years.


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