BNSF to Retire Most ATSF ATS on 2/15/21

On Presidents Day 2021 (likely at Midnight between Sunday and Monday), in a move that was entirely foreseen and entirely understandable (unlike with the UP cab signals), BNSF will retire the Santa Fe era IIATS Automatic Train Stop system that was popular during the first wave of technical railway safety aids in the 1920's and 30's.

Bi-directional ATS shoes under a classic ATSF signal bridge on the Marceline Sub.

 The inductive system, similar to the magnetic Automatic Warning System in UK service, was identifiable by the upside-down canoe shaped shoes mounted to the right of the track.  When activated by a signal displaying an indication other than Clear, the shoes would trigger a warning horn in the cab and failure to acknowledge would result in a penalty brake application.  Set as the most basic requirement by ICC directive for travel 80mph and over after 1948, railroads couldn't abide by its modest cost, resulting in an unofficial nation-wide rail speed limit.  While the Southern, New York Central and Santa Fe maintained hundreds of ATS equipped route miles, all but the ATSF managed to abandon their systems around 1970 with the general collapse of passenger services.  For whatever reason, the ATSF Chicago to LA "Super Chief" route retained its ATS system, allowing the successor Amtrak Southwest Chief to travel for long distances at speeds up to 90mph. 

Inert "always on" ATS shoes protecting a permanent speed restriction on the Marceline Sub

A clever system that could fail safe with just inert steel components, IIATS was in service on the Marceline Sub across Missouri and the Needles, Seligman and Gallup Subs between Barstow and Dalies, allowing for speeds of up to 90mph on Class 5 track.  Unfortunately the system relied on careful clearances between the lineside shoes and the pickup coils, that were mounted, as needed, only on the head end locomotives on freights traveling this territory. Moreover, BNSF went out of its way never to expand the system from what they had inherited, therefore as tracks were upgraded to bi-directional operation, the ATS would remain in the old single direction ABS configuration. In other cases ATS was only in service in one direction on both tracks.  

ATS shoes for westward movements only on both tracks on the Seligman Sub.

The good news is that active PTC is being accepted by the FRA as a valid ATS replacement.  Moreover, in the affected areas since signaling, track and grade crossings are all configured for 90mph, speeds will either remain at 90mph or will be raised to 90mph where ATS did not cover specific directions of travel.  It remains unclear if previously non-ATS territory that is equipped with Class 5 (90mph pass, 70mph freight) track, will see similar speed increases. I have been informed that, similar to the METRA ATS shoes, the timetable for removal is 90-180 days.  However the BNSF ATS territory is probably 10+ times the total route territory, so we'll see.

Railrunner territory semaphore with ATS shoe on the Glorieta Sub.

Due to absent or incomplete PTC, ATS will remain on parts of the Glorieta (controlled by New Mexio Railrunner), Raton, LaJunta and Topeka Subs, however it has been all or partly suspended on most of this territory since the early 2000's, lowering speeds to 80mph where applicable. Due to the nature of how ATS works, I have been told that Amtrak Train 3 and 4 run with the system on, but do not report any activation issues.

ATS shoe on the NJT RiverLINE.  The only instance where IIATS is used as a trip stop.

In addition to the Chief route, ATS will remain in service, enabling 90mph on the former ATSF San Diego route, now playing host to Amtrak Surfliner Trains as well as on the NJT RiverLINE where the technology is used, shockingly, to enforce positive stops at absolute signals.  Anyway, get your photos (or after 2/15 get your ATS shoes) quickly because after President's Day, they could start to vanish without warning.

NYCTA KINGS HIGHWAY Tower Closes

 While I was hoping that the massive COVID related hit to transit would freeze infrastructure "improvements", many transit agencies seem to have kept the faith in Federal funding and use the reduced service plans to accelerate certain infrastructure improvements.  The F route to Church Ave was re-signaled in 2013, closing Model 14 equipped towers at 4TH AVE and CHURCH AVE, which I noted at the time.  This left KINGS HIGHWAY and CULVER YARD as the last remaining towers on the route, with KINGS HIGHWAY having the distinction as being the last elevated main line tower with a traditional interlocking machine, a 44 lever GRS Model 5 (Note the Flushing Line's 111TH ST master tower is also located in a traditional elevated structure). 

Unfortunately due to COVID and obliviousness, I did not get a chance to get out to KINGS HWY before it closed, however well known NYCTA videographer DJ Hammers did a special video on the tower and the re-signaling project, including some interior photos. 

For the lay person, unless the tower is demolished it will look pretty much the same along with the interlocking hardware.  This is in contrast to the underground towers which are frequently cleaned out and plated over. I'm looking for stuff to do this year and getting out to Kings Highway on the F has moved up on the list.

BNSF Moves to Abandon Chicago Cab Signaling

Following in the footsteps of Union Pacific, BNSF has petitioned the FRA to abandon its cab signaling system on the former CB&Q Chicago "Racetrack" Sub between Chicago and Aroura, IL.  In service only for METRA commuter trains, the system dates from the heyday of first generation safety systems following an ICC order in the 1920's.  With PTC being the cited reason, it is now up to the FRA to decide if new technology is an acceptable replacement for the simpler, yet far more resilient safety systems from the 20th century.  Although the burden ostensibly falls on METRA, which contracts BNSF to run the commuter rail service, BNSF is still responsible for maintaining the physical plant.  If the CB&Q cab signals are discontinued, it will be harder to justify METRA's Rock Island district 20 mile segment of cab signals between Blue Island and Joliet.

All of this represents a stunning reversal of fortune for cab signaling in North America as the system has seen robust expansion over the first part of the PTC era as northeastern railroads relied on it to meet the mandate. While Class 1 road NS has also been recently expanding its cab signal territory, CSX has applied to discontinue use of the CSS based ATC system on the RF&P Sub in Virginia.  The latter is less problematic as the ATC only enforced a minimum brake pipe reduction upon cab signal downgrade as is made completely redundant by PTC protections.  CSX has states no intention of removing the cab signals, partly due to the pending takeover of the corridor by the State of Virginia for increased passenger operations.  It remains to be seen if the future 110mph S-Line restoration will feature cab signals or rely solely on PTC.

Bell Tolls for Caltrain's 1907 Signal Bridge

 Way back in 2004 when the San Francisco peninsular commuter rail service known as Caltrain was being modernized with new trains, new passing tracks and new signaling, only a few pieces of Southern Pacific era hardware was retained.  Perhaps the most spectacular of these was the 8 track signal bridge just north of the South San Francisco Station sources claim dates from 1907.

Needed to span a number of freight sidings, the signal bridge was evidently found to be in reasonable condition and subsequently fitted with two pairs of modern signals.  Unfortunately, 15 years later freight service on the peninsula has continued to shrink and a new electrification project has provided capitol money to re-build the South San Francisco holdout platfom and replace the century old lattice steel signal bridge with a modern cantilever. 

While the Bay Area's preservation mindset makes its likely that the signal bridge will avoid being sent to a scrap yard, the electrification project also makes it likely that the signal bridge will need to be moved elsewhere, perhaps to an existing museum, a Caltrain parking lot as an art installation or maybe just the purgatory of the former SP Bayshore shop and yard complex while the powers that be figure out what to do. 

Union Pacific Looking to Can Automatic Cab Signals?

 In November 2017, I learned of a builtin order showing that Union Pacific was shutting down the Automatic Cab Signals (ACS) and ITCS that had been installed on the Lincoln Corridor as part of the multi-billion dollar 110mph upgrade.  (You can see how they operate in this 2012(!) video). 

Although it seemed to be part of the general ETMS PTC rollout and the elimination of the more unique ITCS PTC system I was puzzled that operation of ACS and PTC were to be exclusive, the former only to be cut in if the latter failed. 

13.1.4 PTC/ACS Operations:

The Automatic Cab Signal (ACS) system on the lead unit must be cut out
upon successful initialization of the Positive Train Control (PTC) system and
prior to initiating movement. If the PTC system disengages, is cut out under
authority of the train dispatcher, or otherwise fails en-route while leading
engine is within PTC/ACS territory, the train must be stopped. After stopping,
the ACS system on the lead unit must be cut in prior to any subsequent
movement. If the ACS departure test cannot be performed while on energized
track, a departure test must be conducted in accordance with Rule 13.1.5 at
the train's next forward location where such a test can be performed. If unable
to cut in ACS system on the lead unit, the train must comply with Rule 13.3.3.

Of course this flies in the face of NS's integration of cab signals and PTC, which allowed them to reduce the reliance on a real time digital radio link.I was about to do a post on this situation and how ETMS and ACSES/CSS may be incompatible, but further research indicated that such incompatibility did not exist and I left the post in draft form. 

Well a comment to my previous post on the elimination of IIATS on UP's METRA commuter lines in Chicago indicated that the Joliet Sub rule regarding ACS and PTC had become a System Special Instruction also covering ATS and CNW ATC.

Item 10-B Positive Train Control (PTC) Operations

8. PTC, ACS, ATC and ATS Operations

PTC must be the system utilized by the engineer. Upon successful initialization of PTC all subsequent systems (ACS, ATC, and ATS) must be Cut Out. If at any time PTC disengages, is Cut Out under the Train Dispatcher's authority or otherwise fails, the train must be stopped and the secondary system cut back in prior to any further movement.

This covers a HUGE amount of cab signaled territory stretching from Chicago through Iowa (CNW ATC), Iowa through Wyoming and the Portland Sub in the Columbia River valley.  While the elimination of the clunky 2-aspect CNW ATC system was expected due to its uniqueness, ACS is a standard, 4 aspect, pulse code cab signal system generally compatible with what is used by NS, CSX and the Northeast passenger roads.  As I said before, NS has actually expanded its CSS territory in response to PTC as it solves many problems with radio coverage.  It is also used by Demver's new RTD commuter rail to support a reduced aspect signaling system.

As I pointed out with my NS example, the motivation behind this move is puzzling.  UP went as far as to get FRA permission to operate ACS and PTC trains in mixed company, so there is no technical safety or technical reason that these systems cannot get along.  (BTW, the document is a great primer on how both ACS and PTC are displayed in cab).  In addition to solving much of the issue with a reliable and secure radio path, the FRA PTC regulations also give additional leeway to trains operating after a PTC failure where ATC (as could be enabled by ACS) is still working. 

In theory it could mean an additional test or form, if such a test was not rolled into the existing PTC test.  The ACS antennas behind the pilot are also a potential source of damage that can take a locomotive out of service. I asked around on some forums and the desire to allow foreign leaders on run-through freight was also brought up.  There are also two significant technical issues that may be playing a role.  

The first is that ACS does not map to wayside aspects in the same way PRR/CR/NS CSS due to the lack of strong speed signaling.  For example, Approach Diverging triggers Approach in the Cab while Diverging Clear, Approach Clear 50 and Approach Clear 60 all trigger Clear in the cab.  This cannot really be used to inform a speed based ATC function.  Furthermore, UP never installed cab signal cut points in advance of wayside locations, so the cab signal never drops to Restricting in advance of a Stop or Restricted Proceed signal.  All of this might require intermediate PTC data links to be maintained, or at the very least require specialty programming to deal with the difference between CSS and ACS practice.

On the other hand ACS has at least two advantages that PTC lacks and both are rooted in using the rails to deliver the cab signal codes.  The first is that a train in a Restricted block can take advantage of a ACS upgrade after running its own length (granted not a huge deal with monster freight trains) and the second is that PTC is blind to any sudden circuit shunt in an already occupied block, whereas ACS will immediately fail safe.  The second is likely to result in deadly accidents on an infrequent yet regular basis.

Hiawatha Sub Aspect Change Point near Baileyville, KS

Perhaps the ultimate answer to this question will be what happens on the Hiawatha Sub in Kansas, where UP installed its version of Rule 562 (Cab Signals Without Wayside Signals) on about 60 miles on single track main line.  Google shows PTC antennas in place at what they term Aspect Change Points, which are spaced at twice the frequency of normal wayside signal locations, clearly to ensure that any occupied block has 1.5 miles of Restricting indication behind it. If ACS are retained on this line, it would show that PTC and ACS can function together and that UP (or the FRA) still wants some kind of signal indication to be presented to the crew.  If the System rules apply on the Hiawatha Sub, then we will are likely seeing the first instance of a rail line signaled solely through the PTC system, something railroads have notably gone out of their way to avoid. 

As of 2019 UP had already applied to abandon the ACS so only time will tell if the FRA will grant this and the other requests that will follow.  At this point safety panic might be working in favor of the concept of a secure, reliable in track signaling system that has a lot of what is necessary to allow for 90+ mph operation without costly and time consuming certification processes.  It might be worthwhile in trying to engage in the regulatory process to prevent such a short sighted move.

New Year's Position Light News

 As 2020 winds to a close I wanted to share a few PRR Position Light related news items.  The first is that the Lebanon Mason Monroe tourist railroad in Lebanon, OH, had installed a semi-functional amber PL at the end of the platform at its Lebanon, OH depot.

Next, the LIRR has started to equip its legacy amber PL's with the same type of LED lamps that SEPTA first installed a decade ago at ARSENAL and ZOO.  With all of the reduced aspect signaling and tower demolitions, its nice to see that some of their PLs might have a brighter future. 

Speaking of SEPTA, I reported back in May that the PRR PL's at ARSENAL and WALNUT interlockings appeared primed for replacement, however during my annual winter SEPTA trip I was able to confirm that the signals at ARSENAL, WALNUT and the MP 1.5 southbound PL automatics are all still in place, however the northbound MP 2.0 automatics have both been replaced by color lights.

MP 2.0 automatic half way through replacement in 2019.

That wraps up my 2020 season.  Signal wise, it was not as bad as some other things.  Stay safe and join me again in the new year.

Don't Miss These Updates!

 As we approach the new year I wanted to call people's attention to some internet resources that benefiting from updated content.  The first is the fantastic North American Interlockings archive that I have have featured before, but until i few months ago I assumed it was a somewhat static collection of personal photos, similar to John Roma's.  Well I couldn't have been more mistaken as there are near daily updates.  New photos and text explaining them are linked, by month, from the site navigation column, with the last three months showing.  I tried direct linking to previous months, but those pages seem to be taken down. 😢

In addition to that, the Trackside Photographer, well known for its coverage of signaling and classic interlocking technology, has resumed operations after a brief haitus.  One of my articles, an update of one I posted here about railroad signaling being repurposed, for grade crossing protection, was one of the first of the new batch. 

Anyway, have a Merry Christmas and a great new year.  If you find yourself with some free time over the next few months, make an effort to get out and get some photos of something that might not be around for much longer.