Amtrak's Secaucus High Density Cab Signaling in Action

When the Secaucus transfer was being designed and built around the year 2000, Amtrak implemented a new "High Density Cab Signaling" concept with shorter blocks and additional cab signal codes in order to increase the capacity of the approach into Penn Station especially with all the NJT Corridor and Midtown Direct trains stopping at Secaucus. This would replace the PRR era Rule 261 signaling with mile long blocks. Below we see the 2E signal at ERIE interlocking cycle through its indications after an eastbound NJT push-pull takes a Clear signal upon departing the track 2 station platform. 2E was fleeted for a normal route and immediately went to Stop and Proceed, then Slow Approach, Approach, Approach Limited and  finally Cab Speed (which could represent both 60 and 80mph speed codes). The horn at the end was an approaching Amtrak Regional which ultimately took 2E at Clear (not captured on video).

Unfortunately this was just in time for NJT to lean into Push-Pull service which lacked the acceleration to and braking systems to take advantage of the rapidly changing speed codes. On push-pull sets with traditional air brakes, crews would often target one speed below the one being displayed to avoid jerky train handling and the risk of penalty brake applications in the face of frequent cab signal drops.This negated much of the intended speed benefits from the high density cab signals. For whatever reason, similar High Density Cab Signals could be found on the 2005 era western Harrisburg Line re-signaling, however due to the low traffic density, Amtrak has taken to disabling some of these extra code change points.

NAN Drawbridge: A Crazy Thing We Lost

While this is ostensibly a blog about railroad signaling, I'll sometimes cover related bits of historic technology like railroad telecom systems, electrification systems and drawbridges. Today I get to cover two of those topics at once. Located on the former New Haven Railroad Shore Line, the Niantic River Drawbridge sat at the mouth of the Niantic River in the town of, you guessed it, Niantic, CT. A former New Haven Railroad signaling station, the 1907 bridge would later take the name NAN in the Penn Central and would serve as a staffed interlocking and block station up until the Boston electrification project of the late 1990's. Due to the New Haven being in perpetual bankruptcy NAN saw little in the way of upgrades and was documented by the Library of Congress before the changes of the NEC Improvement Project. While a chain-driven rolling lift bascule bridge is pretty cool in and of itself, it was the electrification project that provided "Old Nan" with one heck of a curtain call.

Railroad movable bridges have to employ complex mechanisms to separate the running rails and unlock the bridge, however when overhead electrification is involved a separate yet equally important system to isolate the contact wire across the movable span must also be employed. Because the 1907 NAN bridge was not electrified for its first 93 years of existence, this system had to be retrofitted onto the rolling bascule span in situ.  

On the contemporary Pellham Bay bridge, which was electrified within a decade of construction, a mechanism isolates the dynamic tension contact wires, while an alternate routing takes the 12kv lines up and over the waterway. The span then rolls back causing the wires across it to sag down to touch the track structure.  (I have seen a photo of this, but cannot currently locate it.) However when NAN was electrified in the 1990's, Amtrak had to use a fancy constant tension solution and in this case that meant a solid aluminum rail type conductor running the length of the span. Now, if you're sharp you might already realize that when the bascule span rolls back, a solid rail can't bend and flex with it. Well, this video shows the solution.  

That's right, a traveling telescoping carriage would move back and forth to extend and withdraw the contact rails from below the rolling structure of the bridge. What's even crazier was that NAN was the busiest drawbridge on the NEC due to a low clearance of 11 feet and a steady stream of boat traffic. Due to complaints from boaters, an agreement with the Coast Guard in 2003 limited closings to "only" 48 per day, so in its final decade of service, Old Nan was putting on quite the show. Unfortunately the 1907 bridge was finally replaced in 2012 by a new bascule span with greater clearance to reduce the need for openings. Fortunately its presence in plain view right downtown allowed for many to personally experience the show and record it for posterity. 

 

MBTA's Everything's Alright Signal

Those who find themselves looking down the MBTA Red Line's distinctive open span subway tunnels might be forgiven if they sometimes think their eyes are playing tricks on them. One moment a lunar white wayside marker signal is visible, the next moment it has seemingly vanished. Those with above average powers of observation might also notice that these signals are facing against the standard current of traffic and also vanish in the minutes before a train's arrival. These are worker protection or "TAK" lights for "Train Approach IndiKator" (also called "snitch lights") and their job is to illuminate when everything is alright, and extinguish when a train is approaching.  

Light on, all clear.

Light out, train approaching.

 

As one might have guessed these use track circuit state to indicate when a train is approaching in a failsafe manner. Placement of the TAK lights appears to have been around curves or other situations that limit the sight lines of track workers. They seem to have been designed for the older single direction ABS system and may only still be in service in the tunnels as the few I have seen on the above ground Braintree Branch appear to be bagged. 

TAK lights are one of those things that you never notice until someone points them out, then you can't help but notice. Back before the real time departure information they were a life hack to know if a Red Line train was approaching, but today, unless you are a track worker, they are mostly a neat bit of trivia. 

LINCOLN Lefty: Story of the PRR's Left Handed Dwarfs

 Anyone looking at the NORAC signal aspect charts may have noticed that the familiar PRR dwarf position lights have a curve to them (or yaw) that can go both ways. For all four dwarf indications, Slow Clear, Slow Approach, Restricting and Stop, one will see two entries on the diagram chart, one with a left hand curve and one with a right hand curve. To the uninitiated this can be dismissed as having to do with clearances or which side of the track a dwarf signal is placed, but it actually represents a fairly early change by the PRR to make a more practical signal vs a more conceptually accurate signal. 

The first PRR position light signals were designed as a replacement for semaphores. Version 1 or "tombstone" position lights (due to the shape of the backing) consisted of 4-lamp lines with an off-center pivot point that directly mirrored the shape and function of a semaphore blade. The position light dwarf signal was no different, but used two lamps to mimic the right to left sweep of a dwarf semaphore. Originally only three positions were provided, stop, low speed prepared to stop and low speed, again matching the function of the dwarf semaphore. 

Between 1918 and 1925 the three lamp system with circular mounting became standard for high signals, but the dwarfs, unable to be simplified further, retained the design aesthetic of a semaphore blade sweeping out a curve. The one major change was that someone noticed that the 4-lamp PL dwarf could display the reverse \ for free and a distinction between "proceed expecting stop" and "proceed expecting obstruction" was able to be made. The result was the left-handed dwarf position light.

Made of cast iron by Union Switch and Signal, the left hand dwarf had bulb access hatches on both the straight and curved sides. The rest was a sealed unit with a small vent on the back. 
 

This model of PL dwarf would go on to be installed at all the great PRR signaling achievements of the 1930's such as ZOO and HARRIS, however the march of progress is never satisfied and the desire to simplify the design merged with the desire to reduce confusion. The new dwarf would be reversed such that the curve would proceed in a high hand direction with the Restricting \ position being reduced in size compared to the Slow Approach / Position. The design was also changed to one with a single large rear access door, possibly enabled through advances in large gasket technology. 

The new style position light proceeded to almost entirely replace the old, especially as the staffed interlocking towers and their electro-mechanical interlocking machines were replaced by CTC starting in the 1970's. By the 21st century left handed PL dwarfs were a rare sight with most appearing at those parts of Amtrak and Conrail territory that had escaped re-signaling since the 1930's. However while out at LINCOLN interlocking on Amtrak's Northeast Corridor in Metuchen, NJ, I spotted a left handed survivor  governing movements out of the MoW yard.

Somehow escaping replacement in the early 90's when LINCOLN tower was closed and re-signaled, LINCIOLN's 5W dwarf is now one of the more accessible left-handed PL dwarfs, mounted on the side girder of the Lake St bridge for all to see.

Hopefully it will escape scrutiny and continue to perform its job for years to come. 

Amtrak's New Position Light Configuration

Following from Pennsylvania railroad practices, Amtrak used the following two configurations for all of its "complete" position color light mast signals at interlockings. They either have a lunar white Restricting \, or they don't. In both cases the single central lunar white Stop and Proceed marker has been retained.  

While most other North American railroads have shifted to using Restricted Proceed in place of Stop and Proceed, Amtrak, and the NORAC rulebook for whom Amtrak is the biggest member, have both retained the Stop and Proceed practice.  

So consider my surprise when saw the recently installed colorized position light signals at Amtrak's new LEGGETT interlocking on the Hellgate Line. The restricting \ is present, but, please correct me if I am wrong, I believe this is the first time I have seen Amtrak PL interlocking signals without a Stop and Proceed marker. 
 

Part of  the Penn Station Access Project, these colorized position lights are the first of many that will wipe out the last stretch of amber position lights on the NEC (PHIL is a point, not a stretch) and they appear to indicate a shift at Amtrak towards that all important stop before entering an occupied block.

In case your wondering the typical Amtrak signal progression is to display a Stop and Proceed if there is an obstruction within the interlocking limits and a Restricting (if available) if the interlocking is clear, but the block beyond is not. The stop certainly seems like a worthwhile safety precaution, but the distinction between it and Restricted proceed is minimal, mostly just the salience of entering a stretch of track with an obstruction or broken rail. 
 

As you can see the new signals on the replacement Portal Bridge have retained the Stop and Proceed marker, but that project was designed and specified some years before Penn Station Access. So it remains to be seen if this is the shape of things to come, or a one off trial. 

 

 

Overland Route Elephant Ear Replacement

Despite its status as an evil empire, Union Pacific has a surprising amount of legacy signaling on its premier transcontinental route between North Platte, NE and Ogden, UT. Sliding just under the falling boom of Safetran scallop-shells and off-brand LEDs, in the late 1980's Union Pacific chose US&S hardware for its overland route CTC project. This includes style N single housing color light signals and their extra large "elephant ear" backings. Similar to multiple projects on the Seaboard part of CSX, the Union Pacific elephant ears managed to survive the 2010's PTC push with the overlay being applied without signal or signaling replacement. 

Well it seems that one major shortcoming has these survivors on somewhat borrowed time. They are still connected to a pole line and here we can see that at least near Sidney, NE, some of the 80's signaling is being removed.  If this is a localized project or something larger remains to be seen, especially if UP's capital budget is constrained in future years.

Signals of the Reading and Northern Lehigh Line

Pennsylvania's Wyoming Valley, today home to the Scranton–Wilkes-Barre metropolitan area, was the West Texas or Saudi Arabia of the 19th century due to its massive reserves of Anthracite coal. A premium product demanding premium prices, anthracite coal was the way that industrializing America kept warm in the water months after the landscape had been stripped bare of trees for firewood. This is how the Wyoming Valley could fund the operations of three major railroads (the Lehigh Valley, Central RR of NJ and Delaware Lackawanna and Western) and similarly explain why those railroads seemed to evaporate without a trace when the world moved on to oil and natural gas.

Perhaps nothing optimized the uniquely American phenomena of direct railroad competition like the LVRR and CNJ, whose main lines were both functionally and in some places literally parallel. In the 1960's the anthracite collapse was well under way and a decade before Conrail, the CNJ had decided to throw in the towel and allow the LVRR to consolidate its operations to Scranton. North of its large yard in Lehighton, PA, the LVRR was able to stitch together a hybrid route, using better aligned portions of the CNJ over the Pocono mountain summit between White Haven and Laurel Run. Later, Conrail would choose to use the CNJ main line between Lehighton and Allentown creating a Frankenstein's monster "Lehigh Line" between NYC, Scranton and NY's Southern Tier. As the region's industry continued to shift, Conrail shoveled off the Lehigh Line north of Lehighton to the upstart Reading and Northern in the 1990's.

All this history is necessary to understand why the signaling on the Lehigh Line portion of the Reading and Northern's main line between Reading and Pittston, looks the way it does. Recently made visible by the series of R&N Iron Horse Rambles and its regular weekend Lehigh Gorge excursion service, the current signaling on the upper Lehigh Line reflect its unique history. In the 2024/2025 time frame I was able to gather enough content to put together a signaling guide covering the old Lehigh Line between Mauch Chunk and Pittston.

We begin at R&N's COAL interlocking, which was built new by them to support the R&N's "Main Line" concept between Reading and Pittston, but also its Lehigh Gorge tourist operations. Using a salvaged lattice cantilever mast, COAL connects what was the old CNJ route to the former LVRR route at the south end of the Lehigh Gorge.

Into the 2000's, Conrail (later NS) owned and operated this portion of the Lehigh Line as a double track Rule 251 main line. Traffic was so light that the southbound track was used bi-directionally with northbound trains needing to get a Form D, while the southbound track had its signal system taken out of service and used for R&M excursions and freights. NS moved first to convert the southbound track to Rule 261 (CTC) operation, with the R&N converting the former northbound track to Rule 261 in the late 2010's. Each track has a single ABS signal location in this line segment, NS at LVRR milepost 126 and the R&N's at its own milepost 124.

A quick note on Mileposts. In the Conrail era the Lehigh Line would alternately use legacy mileposts from the CNJ, LVRR and LVRR Mountain Cutoff. The Reading and Northern switched this to its own mileposts that continues the Reading Company chaining from the old Reading Terminal.  Somehow this has managed to match up with the legacy CNJ mileposts within a few tenths, but LVRR mileposts are off by several miles. I will be using the R&N mileposts for most of this article.
 

CP-M&H JCT marked the transition between double track ABS and single track CTC through the Lehigh Gorge and, starting in the 1990's, the start of the Reading and Northern lease. CP-M&H JCT was re-signaled by Conrail around the time of the lease and has the typical Conrail hallmarks of a CorTen steel relay hut and color tri-light signals. What sets CP-M&H JCT apart is the use of "budget" L&W brand modular signals in the tri-lights. It's entirely possible that the lease arrangement had Conrail responsible for some portion of the signaling system (the interlockings still appear in CR's 1997 signal charts) resulting in signaling that looked Conrail, but with different hardware.

When the R&N lease came into force the arrangement still created a gap in the R&N's conceptual Main Line between Mauch Chunk and CP-M&H JCT where they had to run under Conrail rules and dispatching. When NS finally transferred the northbound track to the R&N in the mid-2000's, they were so thrilled to be in total control that they built a new interlocking back-to-back with CP-M&H JCT named INDEPENDENCE.

The mast is for CP-M&H JCT and the dwarf for INDEPENDENCE.

CP-M&H JCT wasn't an isolated re-signaling as it appears that all of the signaling in the Lehigh Gorge proper was replaced around the time of the lease. This was possibly due to the desire to replace any pole line based system due to the inaccessible nature of the right of way in the Lehigh  Gorge. The new Conrail style signaling again reflected the economic decline of the region with a shift to extra long 3-4 mile signal blocks versus the standard 1-2 mile length. ABS signal locations in the gorge are at R&N milepost 130, 133/134 and 138. The 133/134 location split the Jeddo tunnel for visibility reasons.

134S from behind

It appears that the pole line was retained to supply 440v power to the signal locations, however it is unclear if this supply is still in service.

The end of the 90's re-signaling is at the controlled holdout signal CP-WHITE-HAVEN, which is just a few miles shy of the alignment change from LVRR to CNJ. I do not currently know the status of the CNJ main north of Lehighton prior to 1965, but the re-signaling boundary is surely related to the relative utility of the CNJ signaling versus the LVRR signaling. One possibility could be a post-war investment in CTC by the CNJ to cut costs that exceeded the standard of whatever the LVRR was up to at the same time.