D.C. Metro crash

[MidnightSensi]

http://news.bbc.co.uk/2/hi/americas/8114003.stm

How does this sort of thing happen?

I thought all those trains were automatic and had sensors and such to prevent these sorts of things. Everything just failed? Anyone know anything about trains?

 

[TLS Guy]

http://news.bbc.co.uk/2/hi/americas/8114003.stm

How does this sort of thing happen?

I thought all those trains were automatic and had sensors and such to prevent these sorts of things. Everything just failed? Anyone know anything about trains?

Newer trains have the technology you are talking about. Most trains are old like the one involved in the crash, and were made before the microprocessor and CMOS logic, even if the interiors have had a face lift.

 

[j_garcia]

Newer trains have the technology you are talking about. Most trains are old like the one involved in the crash, and were made before the microprocessor and CMOS logic, even if the interiors have had a face lift.

I was reading an article on it earlier and it said the car that crashed showed no signs of even applying the brakes on this fast section. They also said that this particular car has been in service since 1976 when the line was first started!! The article was the one about the fact that the NTSB recommended removing these older cars from service or retrofitting them with current technology in 2004 after the last accident.

 

[mtrycrafts]

... The article was the one about the fact that the NTSB recommended removing these older cars from service or retrofitting them with current technology in 2004 after the last accident.

Unfortunately, at times it takes multiple such tragedies to correct the problem

 

[Swerd]

The facts are still coming out. I ride the Metro often enough to be quite shaken by this news. It's too easy to imagine what it was like.

All the Metro trains, including the oldest cars, have computerized controls that are supposed to prevent trains from colliding. Unfortunately, these older cars do not have black box data recorders. They are being replaced, but at $3 million each, it is going slowly. They make up about 30% of the total fleet of cars.

The latest word is that the driver of the train that rear-ended the other train had applied the emergency brakes. She died in the crash.

Metro records say that train was 2 months overdue for brake maintenance. One possibility is that the brakes failed.

The front car in that train was crushed from 75 feet long to roughly 25 feet. It probably was not going slow when it hit.

Read more here.

 

[MidnightSensi]

The facts are still coming out. I ride the Metro often enough to be quite shaken by this news. It's too easy to imagine what it was like.

All the Metro trains, including the oldest cars, have computerized controls that are supposed to prevent trains from colliding. Unfortunately, these older cars do not have black box data recorders. They are being replaced, but at $3 million each, it is going slowly. They make up about 30% of the total fleet of cars.

The latest word is that the driver of the train that rear-ended the other train had applied the emergency brakes. She died in the crash.

Metro records say that train was 2 months overdue for brake maintenance. One possibility is that the brakes failed.

The front car in that train was crushed from 75 feet long to roughly 25 feet. It probably was not going slow when it hit.

Read more here.

Interesting! It says that "Investigators also said the striking train was in automatic mode, which means onboard computers should have controlled its speed and stopped it before it got too close to the stationary train. " ... so, looks like the brakes failed... but both the main and emergy brakes? that's unlucky. It looks like it was around a bend, so maybe the operator didn't see the train in front that the automatic wasn't stopping for and only had a bit of time to hit the emergency brakes.

It looks like the NTSB recommended they retire these cars, but Metro just didn't have the money.

A lot of these cities are broke now, so, I think we'll be seeing more of these types of things. I guess we have to evaluate the risk-reward of things. The chances of a train crashing are pretty low, but, we don't have the money to maintain everything like we used to.

I think we will see a lot of things that were built in the 70s start to break up, especially as we approach the end of the aluminums lifecycle in airplanes and such.

 

[speakEZ]

Note to self....When getting on a train...ride in the middle!! Really sad it happened. Too many plane crashes and train wrecks.

 

[mtrycrafts]

... It looks like it was around a bend, so maybe the operator didn't see the train in front that the automatic wasn't stopping for and only had a bit of time to hit the emergency brakes.
....

If so, the wreck seemed like it was straight on as cars on top would be, I think. If both trains were in the bend, I would think the approaching train would hit and go off track? Maybe there was enough of a straight away but still not enough reaction time left?

Just saw a video and it certainly looks like they were in the bend of the run, no straight away. Curious how they piled lengthwise.

 

[j_garcia]

I heard last night that they said a sensor either on the train or the tracks was found to be faulty. That sensor would have sent a signal to this train, as it did with the one in front of it that it eventually hit, to stop.

 

[Swerd]

I heard last night that they said a sensor either on the train or the tracks was found to be faulty. That sensor would have sent a signal to this train, as it did with the one in front of it that it eventually hit, to stop.

Yes, it was a sensor buried under the section of track where the train that got rear-ended was sitting. They ran a test yesterday by parking a train on it, and it failed to signal the central computer that anything was there. So on Monday, the train running behind it may have gotten a clear track signal.

The brakes from the following train were examined and found to be OK. The brakes and track showed signs that the brakes were engaged about 300-400 feet before the point of impact, and the dead driver's emergency brake button was depressed.

No official conclusions yet, but it sure looks like the faulty sensor was a contributing problem. Maybe it was the only problem.