The Washington State Derailment and Positive Train Control


After
more than a decade of planning and construction, a new section of track was
opened for Amtrak passenger service south of Tacoma, Washington on Dec. 18,
2017.  The old route that Amtrak
trains used to take went northwest from Tacoma along the coast of Puget Sound,
around a peninsula named Point Defiance, and then down the coastline several
miles until it crossed Interstate 5 south of the small town of DuPont and
headed south inland.  The new
shorter route uses a bypass track that goes southwest of Tacoma and hugs I-5 for
the rest of the distance, crossing the interstate south of DuPont.  There is a long stretch of fairly
straight track just north of I-5 past a golf course before the track makes a
sharp left turn to the south to cross the bridge over the freeway.

The
problem with the old route was that a number of sharp turns and single-track
tunnels slowed the Amtrak passenger trains down, making the Point Defiance
section something of a bottleneck. 
The project map on the Washington State Department of Transportation website
for the Point Defiance bypass bragged that the top speed allowed on the new
route would be 79 miles per hour.

Rail
fans and others interested in passenger rail transportation made plans to be on
Amtrak 501 as it left the station in Tacoma on the new route.  The engineer, whose name has not yet
been released, was training another railroad employee who rode with him in the
cab. 

In
most parts of the U. S., trains are not operated in a completely automatic
mode, although in many regions a system called Positive Train Control (PTC) is
in operation.  PTC is a kind of
robotic supervisory system that, among other things, constantly monitors a
train’s speed and intervenes if the train goes too fast for a particular
section of track.  About 60% of all
Amtrak trains use PTC, but in order for PTC to work, the track has to have
sensors installed along it, and the Point Defiance bypass was not one of those
routes.  So the engineer was solely
in charge.

Around
7:25 AM, the train was running on the long stretch of straight track before the
turn to the bridge over I-5.  A
properly trained engineer knows what speeds are safe for which parts of a
route, and knows when to apply brakes in anticipation of a lower-speed area ahead,
as passenger trains can take several miles to decelerate at a rate that doesn’t
unduly disturb the passengers.  A
video exists of what was going on in the cab in the last few seconds before the
train reached the I-5 bridge.  The
train was still going at the maximum route speed of 78 MPH.  Six seconds before the bridge, the
engineer commented about the excesssive speed of the train, but by then it was
too late.  The engine and a dozen
other cars left the tracks, killing three, injuring dozens, causing numerous
highway-traffic crashes (none fatal), and closing Interstate 5 for many
hours.  The maximum safe speed for
negotiating the turn was posted as 30 MPH.

Although
the National Transportation Safety Board (NTSB) will not issue its formal
report on the investigation of this disaster for many months, the preliminary
evidence is pretty clear that the accident was caused by human error.  Something—possibly distraction in
conversing with the trainee, possibly plain forgetfulness—made the engineer
neglect to slow the train before the I-5 curve.  As numerous reports emphasized after the wreck, if the train
had been using PTC, it would have automatically slowed down for the curve if
the engineer had done nothing, or even if he had tried to keep the speed
high.  And we have no knowledge of
how many wrecks of both freight and passenger trains have been prevented by
PTC, because by definition such incidents that don’t injure or kill anybody
don’t get reported.  But it is
clear in this case that the absence of PTC was a contributory cause.

Congress
mandated the installation of PTC after the worst train accident in the last
thirty years, a 2008 wreck caused by operator error that killed 24 people.  The original deadline for all passenger
trains to be using PTC was 2015. 
But as the deadline approached and railroads were lagging behind in
their rate of installations—in fairness to them, due to problems with
government regulation of necessary radio frequencies as well as other
causes—they told Congress that if the deadline wasn’t extended, they would
simply shut down.  How serious this
threat was, we’ll never know, because Congress caved and moved the deadline to
the end of 2018.  And under the
current business-friendly administration, we can expect if the railroads ask
for another extension, they’re likely to get it.

Statistically,
rail passenger travel is very safe overall, with the number of fatalities most
years hovering in the single digits. 
Still, nobody wants to be one of the six or seven people who get killed
in a train wreck or hit by lightning—dead is dead, no matter how you go. 

A
utilitarian approach to the issue of PTC and passenger trains might conclude
that, hey, given the low number of fatalities, let’s just allow things to go
the way they’re going, and eventually we’ll have PTC everywhere and we won’t
have to worry about it.  But the
expense per life saved is so high with railroads that we’d be better off using
political and monetary capital fighting automobile traffic accidents or
promoting self-driving cars.

That’s
one approach.  But another approach
says, “Look, here’s this technological fix that will cost the railroads
money and trouble, but will almost completely eliminate what is the last major
remaining cause of railroad passenger fatalities:  human error. 
Let’s bite the bullet and make a special effort, even spend some extra
money, to fix this thing once and for all.”  Maybe that’s the engineering approach, or even the
perfectionist approach (many engineers have perfectionist tendencies).  Yes, the absolute numbers of fatalities
are small.  But deaths in a train
wreck share with deaths in plane crashes a peculiar horror, in that you are
completely bereft of control of the situation.  And in the case of train fans who simply wanted to
experience a new route for the first time and ended up paying for their hobby
with their lives—well, some ironies are too much to contemplate.  I have a good friend who, if he was not
otherwise engaged that day, might well have been on that train, because he
simply likes to ride trains.

Better
training (pardon the pun) of engineers and faster completion of the
installation of PTC are needed. 
And maybe if these things happen, this will be the last fatal accident
involving train passengers for a long time.

Sources:  I referred to several news items on the accident, including
CBS News at https://www.cbsnews.com/news/amtrak-derailment-dupont-washington-video-shows-crew-not-using-electronic-devices/,
a government-run transportation statistics site at https://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/publications/national_transportation_statistics/html/table_02_42.html,
a Washington State Department of Transportation map of the bypass route at https://www.wsdot.wa.gov/Projects/Rail/PNWRC_PtDefiance/Map.htm,
and a report giving the time of the crash at https://www.washingtonpost.com/news/dr-gridlock/wp/2017/12/18/amtrak-train-derails-in-washington-state-rail-cars-fall-onto-interstate-5/. 



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