Thursday, May 23, 2013

CT Train Accident

The crash of two Metro-North commuter trains last week in Fairfield, CT is still a news story here and there, so let's take a look.  It happened on a Friday evening--the FBI showed up that night to investigate and by Saturday morning had turned things over to the NTSB. This report covers it (my bold):
Investigators said Saturday that the crash was not the result of foul play, but a fractured section of rail is being studied to determine if it is connected to the accident. National Transportation Safety Board member Earl Weener said the broken rail is of substantial interest to investigators and a portion of the track will be sent to a lab for analysis.
Weener said it's not clear if the accident caused the fracture or if the rail was broken before the crash. He said he won't speculate on the cause of the derailment and emphasized the investigation was in its early stages. Officials earlier described devastating damage and said it was fortunate no one was killed.
No foul play determined by the FBI before the crash investigation begins, of which the chief NTSB investigator says he won't speculate on a cause.  Except foul play, which has already been ruled out.  OK.

They are focusing on a broken rail (which couldn't have become broken due to foul play, which is great news).  Railroads are constantly sending maintenance supervisors out of the road to visually check track conditions to prevent broken rails, which do occur and cause derailments.  They also use sophisticated detection vehicles to inspect the rails at broader intervals.  According to reports the Sperry Rail inspection machine passed over that section only two days before the accident.   The Sperry machine checks for fractures in the steel, but does it check for loose bolts or failures of the steel "joint bars" used to hold the rails together end to end?  No doubt the NTSB knows and has been closely studying that data.  Other causes are certainly possible--except for foul play, which has been ruled out.

Meanwhile some perspective always helps.  Here is the location of the crash....



Notice that the train had just passed under the Interstate 95 bridge heading eastbound (left to right in the image).  Based on its reported speed of 70 mph the broken rail section would likely have been near or under the bridge.  Try to imagine a horrible train crash on the main Boston-New York rail line happening right under the main interstate between Boston and New York--a terrorist's dream.   Not that terrorists would want to derail a passenger train.

But that's idle speculation.  Going forward, with foul play ruled out, the parties are lining up for blame and payouts. The trainmen's union wants to sue their employer for damages, saying the cars and rails are to blame despite Metro-North not having a major accident in decades and the passenger cars being new.  The politicians are inferring that our transportation infrastructure is falling apart (despite Metro-North's safety record), which is code for blaming the Republicans.  And of course the state will hold hearings to discuss all of this, wherein they will probably find a way to blame the Republicans.

But the NTSB is still in charge. Their report will eventually come out but right now it's an ongoing investigation so they can't comment.  Which seems to be going around.   But it's good at least one cause has already been ruled out.

MORE  5/25/13

The contents of an email from the NTSB has been released stating that the 'joint bat' connecting two quarter-mile sections of continuously welded rail (ribbon rail used on most US mainline railroads) near the crash site had been repaired in April after it was found cracked.  Additionally:
The engineer of the train that derailed, which was traveling eastbound, told investigators he saw “what he described as an unusual condition on the track” just before the accident, the investigative agency said. The NTSB didn’t describe what the engineer had spotted.
This is significant, because it suggests the derailment didn't cause the rail fracture mentioned by NTSB initially on May 16. That supposition could support a couple of possibilities: 1) a sudden failure causing the 'unusual condition' sometime after the last train had passed over it, but before the accident train arrived, or foul play by someone trying to derail a train.  Wait, foul play has already been ruled out--my apologies.

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