It is currently Thu Mar 28, 2024 9:29 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 250 posts ]  Go to page Previous  1 ... 5, 6, 7, 8, 9, 10, 11 ... 17  Next
Author Message
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Sat Dec 23, 2017 11:57 am 

Joined: Fri Mar 26, 2010 11:43 am
Posts: 746
https://www.youtube.com/watch?v=LFx5IGIWO24

scanner audio


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Sat Dec 23, 2017 12:03 pm 

Joined: Sun May 15, 2005 2:22 pm
Posts: 1543
Overmod wrote:
Quote:
Do you have any possible explanation for why the engineer chose to only make an application of the independent brake as he approached the curve?


The explanation given, that the engineer received an overspeed indication from the locomotive and was responding to it, is (at this point in time) the correct one.

For no more than a 2mph reduction, using the blended brake would be almost impossible to modulate - by the time the car brakes had set up and then released, you'd have taken off more than enough to keep you close to the track speed limit. Using the independent is a reasonable way to 'fine-tune' the speed.

Tacit in that, of course, is the presumption (which I think is glaringly correct) that the person in command, whether the nominal engineer or a 'trainee', had no idea about the impending curve. No attempt was made to actuate the train brake, apparently even up to the point the camera sees the crew reacting to the derailing locomotive's movement. That leaves open the question of the time of what was essentially a "desirable UDE", probably due to trainline separation -- fractional seconds on the event recorders becoming significant in analyzing the timing.

If someone could provide a link to the train-radio quote from the head end shortly after the accident, with the 'we were going around the corner' language in it, and a transcript, I'd appreciate it. The person seemed almost chipper about the 'incident' when I heard it in news coverage...


Thanks Overmod. I now see that I misinterpreted this sentence:

“About six seconds prior to the derailment, the engineer made a comment regarding an over speed condition.”

I thought this referred to being over the speed at which it would be possible to reduce to 30 mph in time for the curve; or simply that he was exceeding the 79 mph limit. But, as you indicate, it was an “Over-speed” warning from the instrumentation referring to exceeding the speed limit of 79 mph. The term “Over-speed condition” is the description of a message from an automatic warning indicator, and not just a statement of speed status by the engineer.

And I agree that this does explain the use of the independent brake for the slight and quick speed reduction to needed to satisfy the warning.


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Sun Dec 24, 2017 12:43 am 

Joined: Wed Oct 22, 2008 8:18 pm
Posts: 2226
it sounds like the engineer may have reacted to the 79mph limit perhaps programmed into the engines operating system and reacted to that moment as the train was above that limit.
Were any speed limit signs place at an appropriate distance from the curve for braking?


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Sun Dec 24, 2017 10:56 am 

Joined: Sun May 15, 2005 2:22 pm
Posts: 1543
dinwitty wrote:
it sounds like the engineer may have reacted to the 79mph limit perhaps programmed into the engines operating system and reacted to that moment as the train was above that limit.
Were any speed limit signs place at an appropriate distance from the curve for braking?


My understanding is that there are advance warning signs two miles from the curve which indicate that the train must be prepared to enter the 30 mph speed restriction zone at the curve at no more than 30 mph. So, the speed limit is 79 right up to the start of the 30 zone at the curve. However, engineers must slow down while still in the 79 zone in order to enter the 30 mph zone while not exceeding 30 mph.

The engineer was in the 79 zone when he received an automatic warning from the locomotive speed warning system for exceeding the 79 limit by 1-2 mph. The engineer responded to this warning with the intent of reducing back to within the 79 limit.

And yet, while the system was warning about the 1-2 mph over-speed, there was a much greater speed problem looming as the engineer was apparently unaware and heedless of the fact that he was way over the speed he should have been moving if he expected to reduce to 30 mph in time for the 30 mph restriction at the curve 700 feet head.

So there was a small speed problem and a large speed problem, with the smaller contained within the larger. At the time of the warning at 700 feet out, the train was well past the point where it should have begun reducing speed to 30 mph.


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Sun Dec 24, 2017 11:13 am 

Joined: Wed Oct 22, 2008 8:18 pm
Posts: 2226
when if they reopen this line they should tilt that curve, how much the curve is on the bridge I dunno, just wonder about any side forces it could or coudnt handle.


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Sun Dec 24, 2017 2:12 pm 

Joined: Tue Jul 02, 2013 10:45 pm
Posts: 300
The curve is already elevated just to make 30mph. The curve has been reported to be about 7.5 degrees (if I remember right - I'm on the road and don't have my track charts with me), so 30mph would require at least 2 inches of elevation at a minimum. BNSF always has at least one extra inch, so now it is at 3 inches of superelevation. If you put 6 inches in, generally more than anyone wants, or the maximum legal of 8 inches, you still only get about 40-44mph and now run into clearance issues with the through plate girder span, and issues with stringlining should a train stop in the curve. This extra elevation would not have impacted this derailment much at all.

The junction with the mainline is not far away, so the train should be slowing anyway for that, so spending a great deal of money for this one bridge doesn't make much sense. I remember we were looking at adjusting some curves on the northeast corridor to save 20 seconds or so. To do it, we would have to move the curve, requiring changes in the grade and possibly the removal of several apartment buildings. The math on a curve is pretty complex and it can take significant changes just to impact the speed a small amount.

Bart Jennings


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Sun Dec 24, 2017 6:54 pm 

Joined: Sat Oct 17, 2015 5:55 pm
Posts: 2279
"As the crew traveled south along the bypass route on Monday at close to 80 mph, they would have passed a speed limit sign about 2 miles before the curve. That sign, smaller than a speed-limit sign that drivers would see alongside a freeway, sits in an open area along the track, tilted at a 45-degree angle."

https://www.seattletimes.com/seattle-ne ... -derailed/

Here is a view of the new locomotive controls:

https://www.youtube.com/watch?v=naMesVqFF90

If something was squawking in the cab that the crew was not familiar with (like a 3 MPH over the 79 warning) I could see them missing that little sign, and there apparently wasn't the intense training necessary to make one aware at a glance of the upcoming curve and speed restriction.


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Sun Dec 24, 2017 8:05 pm 

Joined: Fri Mar 26, 2010 11:43 am
Posts: 746
If tracking data is any indication, the speed alarm is going off all the time.
https://asm.transitdocs.com/
When I clicked a few hours after the wreck, it was not hard to find a few trains running in the 80-82 range.


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Mon Dec 25, 2017 12:32 am 

Joined: Wed Oct 22, 2008 8:18 pm
Posts: 2226
They should install a permanent lit speed restriction signal at the point of the sign, not just a sign. Apparently the train knocked down a signal. About the damage on top of the lead engine, the video report says the engine was tilting, this likely put the engine on its side, raked the trees, then landed upright on the highway. All that friction slowed everything fast and bottled up the cars. The evidence of an object on the track still has me curious, so I'll wait if they post the video sometime.

I ran into this poking around.

http://www.projectrepublictoday.com/201 ... ashington/

note the note at the bottom.


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Mon Dec 25, 2017 1:30 am 

Joined: Thu Sep 16, 2004 7:17 pm
Posts: 552
Location: Ballard, WA
Not sure what this thread has to do with Railway Preservation.


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Mon Dec 25, 2017 11:21 am 

Joined: Fri Aug 27, 2004 4:02 pm
Posts: 1742
Location: Back in NE Ohio
Imagine the engineer of #765 or #4449 losing "situational awareness" on a high-speed excursion. That's what it has to do with this. Not likely, but this was an equally high-visibility event. I'm amazed there wasn't a Road Foreman in the cab. Actually, I think on a lot of railroads the RFE would have been running, the regular engineer would have been in the left-hand seat, and there would not have been a trainee anywhere around. I can tell you, as a former engineer, I would not have had any problem with that scenario had I been the engineer of record for such a trip. Takes a lot of pressure off.


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Mon Dec 25, 2017 1:10 pm 

Joined: Sat Aug 28, 2004 5:52 pm
Posts: 559
Location: Apple Valley, Minnesota
Chris Salmonson wrote:
Not sure what this thread has to do with Railway Preservation.


AMEN! And Thank you.

I also object when the railfan talk get mixed-in with preservation topics. I hesitated this go-round so as not to be accused of being preachy.

In any event -- MERRY CHRISTMAS! and HAPPY NEW YEAR!

_________________
Jim Vaitkunas
Minnesota Streetcar Museum
www.trolleyride.org


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Mon Dec 25, 2017 1:32 pm 

Joined: Wed Oct 22, 2008 8:18 pm
Posts: 2226
I've looked at other threads and nobody else has followed this accident with better detail and information. If the mods want to make a new forum area and call it news and put it there, fine, but I doubt it would get the views there. Or eventually move it there if they do that. Lead the title with "News" and maybe readers can choose to skip it.


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Mon Dec 25, 2017 1:45 pm 

Joined: Thu May 24, 2012 1:37 pm
Posts: 2213
It will assuredly be going to Railfanning once the initial investigation has died down.

In the meantime, anyone with common sense will understand that it's not a preservation topic, and avoid it if so inclined.

_________________
R.M.Ellsworth


Offline
 Profile  
 
 Post subject: Re: Amtrak Derailment in Washington State
PostPosted: Mon Dec 25, 2017 5:39 pm 

Joined: Thu Dec 12, 2013 1:26 pm
Posts: 236
I think it is just human nature to be curious about someone else's mistakes, especially if it is in your area of interest. And by extension, failures of equipment and process. This is certainly a reminder of the hazards of being distracted. I wonder if systems such as New York Air Brake's LEADER could have alerted the engineer to the upcoming speed restriction in time for the train to slow to 30 mph. I realize that it doesn't have all the features of the PTC, but the system might have been effective in this situation plus the accident in North Philadelphia, for a lot less money. The LEADER or GE's Trip Optimizer could have been deployed on all Amtrak engines by now. On a lighter note, I noticed that the speed restriction sign had P and T on it, T for Talgo. I also used the Open Railway Map to see the site of the mishap.


Offline
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 250 posts ]  Go to page Previous  1 ... 5, 6, 7, 8, 9, 10, 11 ... 17  Next

All times are UTC - 5 hours [ DST ]


 Who is online

Users browsing this forum: Google [Bot], Majestic-12 [Bot], The_Pine29 and 98 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to: