Wasn't it T.S. Eliot, that..er... should we say conservative poet {as opposed to what? hidebound? rigid? dull? all three?) who said "April is the cruelest month"?....
THEY'RE FROM THE GOVERNMENT, I'M HERE TO HELP
...Yeah, it was, and maybe he worked for a railroad. Once.
A year ago, near Creston, Iowa, a BNSF freight train operating under a restricted speed indication, didn't. The freight train ran into the rear end of a MOW train stopped in the block. The collision killed the engine crew on the BNSF freight train.
Maybe March is the cruelest month. This March, two passenger trains collided head-on in Poland, at speed, indicating to me at least (me who still dreams of forgetting to attend a college class until the day of the finals, something I never did; me who still dreams of writing the dreaded "lap" order, also something I never did), that somewhere, somehow, somebody issued overlapping authorities.
I bet, given enough time, and access to Google, every month is the cruelest month. February in Seacaucus, NJ 1996; September in Chatsworth, Ca 2008; January in Chase, Md 1987., November in Livingston, La 1982... etc. etc. and way too many etcs.
Anyway, the National Transportation Safety Board, an organization I would love to admire, as I would love to admire the FRA (and which organizations I defend, to the wall, against "de-regulators," "free marketeers," Ayn Randists, Friedmanites, neo-Austrians, neo-con neo-liberal non-Austrians, self-styled Adam Smiths-- or as I call them, "Smithereens"), has delivered its determination of the cause of the BNSF collision on the Creston subdivision. You can read the press release for yourself at: http://www.ntsb.gov/news/2012/120424b.html.
Please do. The last thing I want is for anybody to take my word for something simply because it is my word. Lord knows I never took anyone's word for anything in my railroad career, which had some interesting repercussions on my career path. Just ask the VPOs I worked for.
The NTSB has determined that crew fatigue was the probable cause of the collision in Iowa, and I don't doubt that. Nothing puts crew members to sleep faster than operating at 10-20 mph in daylight hours after being called to work in darkness. Used to be, railroads had rules against operating continuously at speeds between 12-22 mph [or in that area], a rule based on the possibility of triggering a harmonic rock-off derailments on jointed rail as 12-22 mph somehow reached the "natural frequency"-- the resonance causing the wheels of the cars to lift off the rail.
Then welded rail came along. Me? I still think that prohibition should be in the timetables, as 12-22 mph seemed to be the "natural frequency" for every locomotive engineer I ever worked with, putting him [they were all men] to sleep. I sure as hell know it was my natural frequency... so much so, that I would go outside the cab and sit on the porch of the locomotive to keep myself awake, so I could remember to go in and wake the engineer if something appeared wtihin half my range of vision. Trust me, I did exactly that, and I'm alive to prove it.
So fatigue caused that collision. No argument. But after that? After that, NTSB writes, "Contributing to the accident was the absence of a positive train control system that identifies the rear of a train and stops a following train if a safe braking profile is exceeded."
Nice turn of the phrase that: "...a positive train control system that identifies the rear of a train and stops a following trains if a safe braking profile is exceeded."
Ummh......not to put too fine a point on it, but PTC as stipulated by FRA (see previous remarks about wishing to admire) does not, needs not, identify the rear end of any train under any circumstances. I don't even know that if, in all the years PTC was on NTSB's "ten most wanted list," NTSB ever stipulated that PTC should be able to enforce a positive stop on a train following another train.
No, what FRA requires is that PTC enforce restricted speed and what is restricted speed? Simply the stop gap, the place holder, the admission, that years ago, the technology was such that railroads had no way of positively determining and identifying the rear end of a train by any apparatus independent of a human observation-- there was NO field process to accomplish this, as opposed to an office process. And in this case, the cab of the following locomotive qualified as an office.
What has been the basis of the great contribution that signal engineers have made to both throughput and the safety of railroad operations?
Digression ( but not really):
(I would like to take this opportunity to tip my NY Yankees baseball cab to the signal personnel, I've met, I've talked to, I've worked with in my career, and in particular the signal maintainers, engineers, designers, supervisors, managers, directors, and chiefs that I was fortunate enough to work with at Metro North Railroad who live and breath safe separation of trains)
Anyway, that great contribution was-- the separation of field authorization from office request, that is to say the mechanism for requesting the authority for movement (or a signal indication) was not identical to the mechanism awarding the authority for movement (or displaying the signal indication).
Back in the day, and today, the train dispatcher, in dark territory, requested and issued the movement authority, relying on a train sheet, and his/her memory of the rules, the vital logic of the railroad, to prevent overlapping authorities.
Our signal engineers, took that vital logic, embedded it into interlocking machines, and then extended that logic, the principles of operation of those machines to the entire railroad through CTC systems. Good for them, and good for us.
But as good as they were, and are, the signal personnel can only design for safe separation of trains to the degree that train positioning information technology will support that design.
FRA, in its finite wisdom (no offense, wisdom only is to the extent it is finite) has subordinated that technology to the (archaic) (obsolete) limits of signal design. Hence we get the enshrinement of restricted speed for following movements instead of its abolition.
It gets better, or worse, because the BNSF collision near Creston, occurred with the following train opeating at...23 mph. The numerical value that is accepted in lieu of the real meaning of restricted speed is........20 mph, so it's quite possible that this BNSF would not have triggered a penalty application of the brakes even as its speed crept about the 20 mph mark.
And after all that? OK, here's the short version, the skinny. If we're going to do this, let's do it right. If we're going to establish a braking curve to prevent overrunning authorities, then we have to establish a braking curve that can be calculated between the rear of a leading train and the head end of a following train.
I mean, we are spending billions, aren't we?
dms
April 27, 2012
Be well. Do good work. And keep in touch.
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