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Thursday, April 29, 2021

AR Tower - Hanging In There.

As with my previous post on the state of MG tower, I can confirm that AR tower is in a similar state of limbo, partly gutted of some components, but left standing and even more open to the elements.  I found this video tour on YouTube showing the current state of AR Tower, but also the adjacent 100hz power house and compressor hut.  Shockingly, the double Model 14 interlocking machine is still in place and roughly in the same condition I found it back in May of 2018.



If everything plays out right I should be able to revisit AR tower towards the end of May.

Saturday, April 24, 2021

FAIR Minus Air

 As I previously reported in 2019, Amtrak's FAIR interlocking in Trenton, NJ was having its pneumatic point machines replaced by electric M3's.  I can confirm that this process has been completed and the air compressor infrastructure generally cut and disabled. 


FAIR was one of the larger pneumatic plants remaining on the NEC, however a few others still remain such as HOLMES, PENN, RIVER, POINT, BAY, CHARLES, FULTON and LANDOVER. Of those PENN and BAY have been partly replaced and LANDOVER is slated for complete replacement by a new set of high speed crossovers. The New York Penn Station complex is also still pneumatic and is actually seeing refurbished A-5 point machines installed with the general rebuilt of the trackwork there.


Friday, April 16, 2021

PHOTOS: GREENBELT - The Last CPLs

In the fall of 2014 CSX completed multi-year re-signaling efforts in the heart of its former Baltimore and Ohio territory that included the Philly, Capitol, Metropolitan and Cumberland Subdivisions. B&O style Color Position Lights, some installed as late as the 1990's, were replaced by the typical hooded traffic lights. Beyond the odd siding exit, drawbridge, diamond crossing or distant on non-signaled track, the main line CPL era east of the Ohio River was over. There was however one notable exception on CSX in the form of GREENBELT interlocking in Greenbelt, Maryland. Located just inside the Beltway adjacent to the DC Metrorail-MARC transfer station of the same name, GREENBELT was distinctive in being an interlocking that only really served the MARC commuter train service. These CPL signals would stand for an additional 6 years until their replacement in late 2020. In May of 2020 I went out to GREENBELT for a documentation run so I could present to you photos of The Last CPLs.


GREENBELT interlocking was installed in 1992 as part of a general re-signaling of the Capitol Sub to better support the MARC Camden Line. This saw the elimination of any residual Rule 251 ABS territory, a new Camden terminal complex in Baltimore and the closure of any remaining manned towers such as JD TOWER in Hyattsville. Both the Capitol Sub project and a similar one on the Metropolitan Sub turned out to be some of the last where B&O CPLs were installed new. Like several of the new Capitol Sub interlockings, GREENBELT was commissioned solely for the benefit of MARC commuter trains and consisted of two side pocket tracks that would provide an ADA compliant high level platform connection to DC Metro's new Green Line terminus (The The Americans with Disabilities Act having recently come into force). Pocket tracks were necessary as high level platforms conflict with the clearance envelope of main line North American freight trains. The interlocking consists of two switch pairs, #1 and #2 and 4 signal pairs, 1E/1W. 2E/2W, 3E/3W and 4E/4W.



The signals were in turn broken down into 4 high mast CPLs for the main tracks and 4 dwarf CPLs for the pocket exits. The dwarf signals were placed following the old "right hand" style, while the high masts were not.



In addition to the 12 o'clock orbital for normal routes, eastbound main track signals sported 6 o'clock orbitals for Medium speed diverging movements into the pocket tracks as well as 10 o'clock orbitals for Approach Medium indications for crossover routes at AMMENDALE interlocking, one full signal block beyond GREENBELT.


Eastbound pocket track signals featured a 6 o'clock orbital for diverging routes back onto the main line as well as an 8 o'clock orbital for Medium Approach Medium indications when trains needed to immediately diverge again at AMMENDALE.


 
The westbound signals have a slightly more complicated history. As originally configured westbound main track signals featured both 10 o'clock and 2 o'clock orbitals for Approach Medium and Approach Slow indications respectively. This is because GREENBELT was also one signal block away from the former JD TOWER complex in Hyattsville. Trains approaching from the east would get an Approach Medium for track 1 to 2 crossovers or routes onto the Alexandria Extension at RIVERDALE PARK interlocking. However if a Stop signal was displayed at JD TOWER interlocking, a Slow Approach indication would be displayed (at least for diverging routes) at RIVERDALE PARK due to the short block distance between RIVERDALE PARK and JD TOWER. This then necessitated an Approach Slow capability at GREENBELT.


The westbound dwarf signals operated in a similar manner, just with a full row of lower orbitals including an 8 o'clock orbital for Medium Approach Medium and the somewhat rarer 4 o'clock orbital for Medium Approach Slow.

Tuesday, April 6, 2021

What the KCS - CN/CP Merger Means for Signaling

 A few months ago I discussed the absolute signaling disaster the potential purchase of Pam Am by CSX would be.  Since rail mergers are suddenly in vogue again, Canadian National and Canadian Pacific are nowboth bidding for Kansas City Southern and I am sure at least someone out there is interested in what this will mean for the signaling on the KCS.

To make a long story short, not much.  Not only is KCS pretty much entirely Darth Vader masts or slightly older traffic lights, both CN and CP are good about preserving the unique signal rules of their subsidiaries.  For example the CN owned Grand Trunk Western route uses a very NORAC style speed signaling system.  That feeds into the CN owned Illinois Central that still uses a bland weak route signaling system, which is also distinct from the CN owned EJ&E's signaling system. So yeah, don't sweat this one, just sit back and enjoy the C40-8s or SD70ACUs.