9 Dead in DC


I was watching this coverage yesterday and have same thoughts I had about the crash in Boston a few weeks ago - why no automatic train stop? This is such old and proven technology that I can't understand why it's not used routinely on all railroads and transit systems. One again, it seems the train operator must have been seriously distracted by something, since she ran two red signals and made no attempt to brake before hitting the standing train, which was waiting on a red for another train to clear the station. Whatever the reason for her apparent inattention, she paid with her life, as did at least 8 other passengers. :( I hope this accident spurs the adoption of ATS as mandatory in the future.
 
the drive could have had a medical problem... There was a horrendous London tube crash years ago where a train ran into a dead-end tunnel. The driver was seen at the controls appearantly incapacitated.

also, how about that Continental Airlines pilot who passed away at the controls of a Brussels-Newark 777? Co-pilot thought he had just nodded off for a few sec... (he was in perfect health. He lived down the street from me where I lived growing up. Saw him as recently as last sept.)

some things we will never know...
 
V&AL, that pilot was my sister's brother-in-law. He just had his six month physical the week before and passed with flying colors. The autopsy showed he died from a third degree heart block. There was a cardiologist on board and they had an AED but there's nothing you can do about a massive heart block if you're not in the hospital and, sometimes, not even much you can do then. :(

Nevertheless, automatic train stop would have prevented the DC accident if the operator was dead or just not paying attention. The train would have automatically been bought to a stop when it blew the first red. There's just no excuse for not using this kind of technology when it's easily available.
 
Alerters & dead man switches

These trains do have dead man switches. Either you have to keep 15 pounds of pressure on a sprung throttle or touch something every 15 seconds to keep the brakes from applying incase you pass out while at the controls.

NYC_George
 
supposedly they DID have ATS:

Computer failure may have caused D.C. train crash

WASHINGTON – Investigators looking into the deadly crash of two Metro transit trains focused Tuesday on why a computerized system failed to halt an oncoming train, and why the train failed to stop even though the emergency brake was pressed.

At the time of the crash, the train was also operating in automatic mode, meaning it was controlled primarily by computer. In that mode, the operator's main job is to open and close the doors and respond in case of an emergency.

Debbie Hersman, an investigator with the National Transportation Safety Board, said it was unclear if the emergency brake was actually engaged when Monday's crash occurred. But the mushroom-shaped button that activates it was found pushed down in the operator's compartment.

The train plowed into a stopped train ahead of it at the height of the Monday evening rush hour, killing nine people and injuring more than 70. It was the deadliest accident in the 30-year history of the Metro.

Crews spent Tuesday pulling apart the trains' wreckage and searching for victims' bodies. And authorities worked to determine why the train's safeguards apparently did not kick in.

"That train was never supposed to get closer than 1,200 feet, period," said Jackie Jeter, president of a union that represents Metro workers.

Full article:
http://news.yahoo.com/s/ap/20090623/ap_on_re_us/us_dc_metro_train_derailment
 
That's why commercial aircraft have redundant systems. Computer control is great...when it works. You can back it up with a simple track induction system, where the current in the track changes when you pass into a red block. No action in five seconds and the brakes are automatically applied just by dumping the air. I have no idea what type of braking system is used by the DC system but putting your faith in one system when you're running in automatic mode is foolish at best and, as we've seen, fatal at worst. Apparently this train set was about 30 years old and there's talk of some kind of brake failure. If that's the case, the DC Metro system has a lot of explaining to do. There's no reason a well maintained 30 year old trainset shouldn't operate flawlessly. The railroads have hundreds of 30 year plus locomotives running every day so age seems like a poor excuse to me.
 
The unit that failed was tagged to be replaced three years ago. Someone should lose their job. Unfortunately, if there's no money for new units, there's no money.

Bob
 
And thanks to Congress there will be no money to upgrade many other systems either because of the PTC mandate by Congress, the commuter lines will have to spend billions of dollars by 2015 to install PTC.
 
That's why commercial aircraft have redundant systems. Computer control is great...when it works. You can back it up with a simple track induction system, where the current in the track changes when you pass into a red block. No action in five seconds and the brakes are automatically applied just by dumping the air. I have no idea what type of braking system is used by the DC system but putting your faith in one system when you're running in automatic mode is foolish at best and, as we've seen, fatal at worst. Apparently this train set was about 30 years old and there's talk of some kind of brake failure. If that's the case, the DC Metro system has a lot of explaining to do. There's no reason a well maintained 30 year old trainset shouldn't operate flawlessly. The railroads have hundreds of 30 year plus locomotives running every day so age seems like a poor excuse to me.

That's the thing about this---NTSB ordered Metro to replace the trainsets but no one asked ----
" and how do we replace these trainsets with NO MONEY?"
Apparently, Metro does not have a stable source of funding? So how are they supposed to perform their mandate with no stable source of funding?
 
The requirement for Positive Train Control (PTC) is a good thing for passenger safety. That bad thing is that Congress mandated a very complex and expensive system with no thought as to how transit systems and railroads could pay for it. There's also a huge issue with interoperability, with at least eight companies offering PTC systems, none of which are compatible with each other.

As far as DC Metro's never ending funding problems, the answer is to simply shut down the system when they run out of money. They keep trying to limp along with inadequate funding, which affects service and passenger and crew safety. I'm willing to bet that the respective governments served by DC Metro would come up with a funding solution if the trains stopped running for a week or so.
 
manual brakes

The thing I don’t understand here is that I thought they said the visual signals were also being used along with the train control. If you just passed a yellow over yellow signal and you’re doing more than 45 mph the train control should automatically sound an alarm and reduce your speed. This should also happen at the approach 30 mph and stop signal 15 to 0 mph . If you’re not hearing an alarm and the train control is not decreasing your speed then you would start applying your own brakes. If their not working then you would engage the manual brake which would exhaust the air in the brake line stopping the train.

NYC_George
 
George, I think the issue is that DC Metro operators aren't really operators. Much like BART in San Francisco, the trains are under computer control and the operators just monitor the doors and notify the authorities if trouble breaks out on the train. This operator had only been on the job for less six months and was previously a bus driver. I don't know how much training they get about what to do in case of a computer failure but I doubt it's very much. Running though a yellow at top speed may not have even registered in her mind as a problem. What I really don't understand is that there are train control supervisors at the Metro headquarters who monitor all the train movements as well as a computer system that should notify them when there's a fault condition. Like all accidents, it takes more than one thing to go wrong, and they all have to wrong in the right sequence. There was apparently a computer failure and the supervisors didn't recognize (or weren't paying attention) when the screen showed the two trains with one closing at top speed and not slowing. Add that to an on-board operator who probably didn't realize what kind of trouble was about to occur and you have all the makings of a tragedy.
 



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