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.

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. 

 

 

View From the Head End

Recently a Youtube channel appeared called View From The Head End, that was posting complete head end cab videos from Amtrak trains. These were not the more typical "reversed" videos taken from a rear facing window, but legit head end videos that documented both signals and signaling. More significantly the videos were up to date, likely all recorded within the last couple of years. My first thought was that someone had recently retired because since the early 2000's Amtrak (and I assume most railroads) have been somewhat anal about employees moonlighting as content creators. Well, I guess they hadn't retired because if you haven't noticed the link is broken and the entire channel is gone.

While the practice of workers recording head end videos to feed Youtube channels seems to be quite common in Europe (where I should add its practically impossible to fire railway workers), there are surprisingly few full-line inside-the-cab videos from North America. Up through the early 2000's there was a cottage industry head end videos being sold at "Train Shows" on either VHS or DVD. Some of these were professionally produced by outfits like Pantex, while others were made by AV savvy employees with access to a Hi-8 camera and a capture card. Unfortunately the rise of The Internet brought this wildcat era of video to an end as the speed of information made it easier for previously underground works to become known by regulators, the media and lawyers.

In the early years of Youtube, spotty internet connections and the more ephemeral nature of online data encouraged folks to save off important video content like head end videos. This practiced has decreased as the internet became more reliable overall, however when you find something that seems too good to last, you might want to leap into action and save off a local copy. In a sliver of good news I was able to watch some of the videos before they vanished and resolve some outstanding signal questions I had.

Meanwhile if you'd like something similar to watch I can provide two pairs of videos from the late 2000's covering an Acela trip from Boston to NYP (head end) and the Former Conrail Chicago Line between Buffalo and Albany (rear facing). Intended for Train Show (tm) sale both had been scrubbed of ambient cab sounds and the Chicago Line also being video reversed (which I was able to undo). Although mostly silent, the Chicago Line video in particular captures the NYC/Conrail signaling immediately before its complete replacement ~2010.

New Pittsburgh Line Interlockings

Norfolk Southern's ability to extort the state of Pennsylvania to add additional passenger frequencies on the old Pennsylvania Railroad Main Line is resulting in a slew capacity expansion projects in the form of "new" interlockings and additional tracks. I use the quotes as some of the interlockings are actually restorations of those that existed within living memory, but were removed for the sake of efficiency. 

Restoration of the old SG and NY interlockings.

The first phase of this work is underway at the set of the old SG interlocking west of Johnstown. The new crossovers will allow Amtrak trains to use both sides of the single island platform that serves tracks 2 and 3. Currently if track #2 is unavailable, trains must use main track #3 which follows the slower route of the old Sang Hollow Extension for 15 miles between CP-CONPIT and CP-C since SG interlocking was removed by Conrail around 1980. 

Returning 3 tracks to the Rockville Bridge

Additional changes include the restoration of CP-WEST PITT, removed by NS around 2007, a new crossover on the West Slope near the old NY interlocking between CP-SO and CP-MO, a new third main track between CP-ALTOON and CP-ANTIS, a new interlocking on the Altoona raceway between CP-ANTIS and CP-GRAY and another third main track between CP-BANKS and CP-HARRIS, which would restore a third track to the Rockville Bridge which was lost around 2000. Summary details of the project can be found here with a 2021 report providing more details of the track and interlocking changes. Note the report is not gospel as photos of the new CP-SG show parallel crossovers instead of a universal crossover.

Although no longer equipped with Conrail/PRR era signals, the NS Pittsburgh Line is still Rule 562 cab signaled with "C" lamps, so more interlockings means adding signals where automatics were previously removed.

Clear to Next Interlocking Rule 280a Displayed at CP-SOLOMON (EAST PITT)

In NORAC-aligned cab signal territory where wayside intermediate signals are not provided, Rule 280a, "Clear to Next Interlocking", allows trains without cab signals to proceed under signal indication instead of needing a track warrant or moving at Restricted speed. Related to the old concept of manual block clear, Rule 280a consists of a flashing lunar white light under the letter 'C' adjacent to a wayside controlled signal. These are normally pretty hard to catch in the wild because they are intended to be used to remedy en-route cab signal failures which are both rare and impossible to predict. For a time it was policy for Norfolk Southern dispatchers to run some Amtrak trains under absolute block protection and I was informed that some would display the  Rule 280a "C Lamp" where available, but I never managed to observe this practice for myself. 

That being said I did stumble upon a scheduled use of Rule 280a that one can catch if they are ever in the Pittsburgh area. After arriving at its Pittsburgh terminus, Amtrak Pennsylvanian Train 43 must reverse about 5 miles to CP-HOME where the closest turning wye is located. Because the rear coach lacks cab signal capability, the "C lamp" is displayed in along side the interlocking signal at CP-PITT, CP-EAST PITT (aka CP-SOLOMON), CP-BLOOM (if necessary) and depending on the order of the wye move, CP-HOME. 

Somewhat ironically the first three interlockings, CP-PITT, CP-EAST PITT and CP-BLOOM, are all back-to-back with no code change points between them. NS could have designated that track segment as normal Rule 261 without the "C" lamps, but their policy followed that of Conrail to provide the "C" even where it is not necessary. (Amtrak had chosen to do the opposite up until about 2010).

Anyway, here we see the 2E mast signal governing track #1 eastbound at CP-SOLOMON (EAST PITT) on the former Conrail Pittsburgh Line displaying Rule 280a in conjunction with a Medium Clear indication reverse move of Amtrak's westbound Pennsylvanian Train 43. CP-EAST PITT is only about half a mile from CP-BLOOM and directly adjacent to office parking making it and ideal spot to Rule 280a in the wild. 

I got this video from the east end of CP-PITT, which a shorter walk from downtown. About 30 minutes after its outbound passage, Train 43 will get more more "C" lamps displayed for a second long reverse move back into Pittsburgh Penn Station however the 2W signal at CP-PITT will display a Restricting into the station track without the "C" indication.

No Approach! The Duality of Uncommon Signals

We all learn about traffic lights in elementary school.  Red means stop, green means go and yellow means slow or caution. These are the basics of automatic block signaling that also tend to get taught in entry level railroading books. Now its pretty logical that a signal might lack the ability to display a clear indication. A permanent stop condition or the end of automatic block territory are both situations where a Clear signal would not ever apply. However there are a few situations where signals in North America can display Stop or Clear, but not Approach on the full speed head. 

The first is at interlockings outside of automatic block territory like a diamond crossing or drawbridge. The signal provides movement authority through the interlocking and without track circuits outside of the interlocking limits there is no "prepare to stop" points an Approach type signal would apply to. Trains will have their own movement authority like a track warrant so a clear signal is basically the interlocking telling the train "you do you". One might expect signals in this case to display a Restricting indication, instead of a clear, and sometimes they do, but that is going to come with a 20mph speed restriction, or less, which can be a time hit on unsignaled lines with higher track speeds. 

The next situation, Manual Block territory, would be very familiar to those in other parts of the world. Although almost extinct in the US, there remains a bit of manual block still in service on the LIRR and the way to identify a manual block signal is the lack of an approach indication. (This also applies in general to historic PRR signaling charts.) Signals will display Stop or Clear Block with any Approach functionality handled by a separate distant signal towards the end of the manual block. The PRR even went one further sometimes substituting the \ "Caution" indication in place of / Approach. 

Sometimes its really not good to have locomotives stopped and waiting at a specific signal,  Maybe there's an issue with a grade crossing, or noise, or diesel exhaust. In this case it would not be desirable for trains to approach that signal prepared to stop, so a preceding signal will either hold trains short or allow them to approach a signal with some sort of proceed indication. The most notable of these is at the entrance to Washington Union Stations 1st St tunnel that the currently diesel hauled northbound trains cannot enter without having a signal displayed further on that allows them to leave said tunnel. Another nearby signal location at CSX's LENFANT interlocking might lack southbound approach signals for a similar reason due to an overbuild.

One somewhat PRR-specific situation is where interlockings are provided with exit signals and because of the short distance between the interlocking's entrance signal and exit signal, Slow Approach is used instead of Approach. This creates an upper head that can only display --- Stop or | Clear. The C&O also made frequent use of exit signals, but seemed to keep their upper head Approach indication, although Medium Clear to exit Approach allowed the C&O to minimize the use of R/Y/Y/ Medium Clear.

A fairly new situation where Approach has been "omitted" involves high speed turnouts. At certain points on the NEC, Amtrak has decided to combine a flashing green "Cab Speed" signal indication with R/*Y* Medium Approach. At the end of a main track that converges into another via a high speed turnout, the result will be an upper head with green and red lamps/positions and no yellow lamp/position.
 

New Signals Up At THORN

 Although not much has changed regarding the ultimate fate of THORN tower, recent photos do show what the new signaling situation is going to look like. In the eastbound direction the triple signal bridge covering tracks 1, 2 and 5 Running, have gotten the Safetrain upgrade with Rule 562 'C' boards turned. Although not yet in photos, it is expected that track 4 will also be getting a PL mast signal to replace the existing reverse direction dwarf. SEPTA is tentatively resuming service to Coatesville upon the completion of new station facilities in 2025 which includes a semi-restoration of #2 track to a point just past the new station for the daily NS regional freight. 

In the westbound direction new PL masts are up on tracks 1 and 2 to replace the reverse direction dwarfs and its assumed that a new gantry mounted signal will be in store for #4 track.  The real surprise is what looked to be a new westbound full PL mast signal on what used to be the Low Grade Freight Line track. The old THORN had maintained a vestigial signal in that same location, but despite the rationalization of the former 6-track full crossover, it seems the low grade stub track has not only been retained, but is being prepared for use. What that use might be remains to be seen, but a mast capable of displaying Medium and Limited speed signals could imply SEPTA trains making some sort of switchback maneuver after discharging on Thorndale's track #4 platform or coming out of some yet to be built storage tracks on the footprint of the old PRR Thorndale facility. 

The THORN interlocking cutover is still planned for later in June with DOWNS to lose its switches before complete removal. GLEN and FRAZER will be turned over to the dispatcher by the end of 2025 closing THORN as an active interlocking station.

Harrisburg Power Office Is Now Mostly Up and Running

When we last checked in on the Harrisburg Power Director's office about a year ago in 2024, the Big Board had been fully illuminated and most of the Westinghouse "Visicode" SCADA equipment had been reactivated with the help of modern technology simulating the presence of the field equipment like substations and such. However, because the 1930's PRR electrification projects had been funded with depression era WPA loans, the PRR had to spread the wealth and about half the office used GE "Code Selector" hardware that was more complex in operation and not as well documented. 

Well between March and September 2024, members of the Harrisburg Chapter NRHS managed to locate the documentation for the GE gear (it was sitting on a storage shelf) and were then able to restore most of the GE panels to operation, which is especially useful that represents the bulk of what was still operational on the old PRR Main Line up through 2013. The GE gear brings the added fun of step switches being used to store digits instead of all-relay registers for the Westinghouse part of the office.

As if step-switches weren't enough, between September 2024 and March 2025, the team also reconnected the alarm lamps and bell which further adds to the effect.

Still to be addressed are the metering circuits along with programmed simulation elements that would allow visitors to participate in directing flows of 25hz power to virtual train movements. Still, the Harrisburg power office  is mostly complete in terms of being "a thing that functions as it once did" so watch out for planned opening dates as the chapter is still trying to figure out how to manage regular hours.

DOCK Movable Bridge to Become DOCK Bridge

In 2017 the great DOCK tower closed as a staffed interlocking station after about 80 years of service. However the imposing structure retained one last official duty beyond "employee lounge" and that was housing the controls and auxiliary equipment to work the adjacent three span vertical lift drawbridge situated between the tower and Newark Penn Station.

 

Unfortunately the Passiac River was not the industrial thoroughfare of years past and unlike the nearby PORTAL bridge whose low clearance made it subject to periodic openings for barge traffic, the height of the DOCK draws is sufficient for the dwindling commercial traffic on the waterway.  After not opening a single time in 2024, Amtrak has petitioned the Coast Guard for permission to permanently close the bridge.

While it is unlikely that anything will happen to the bridge, Amtrak will no longer have to maintain the operating equipment, interlocking logic and the mechanisms used to make and break rail and overhead wire continuity.

DOCK draw actually contains three independent movable bridge spans. A large 3-track north span for mostly westbound Amtrak and NJT trains, a 2 track span for PATH rapid transit trains and a single track span for mostly eastbound Amtrak and NJT trains. The PATH span was set at a higher clearance above the river to reduce the number of openings on what was higher frequency rapid transit line.

 

One interesting quirk was the use of standard point machines to work the rail locking mechanisms at least on the PATH tracks. 

Based on the general interlocking layout I would not expect many signals to move, although the eastbound signals on tracks 2 and 3 might be moved across the bridge to resolve possible ACSES positive stop issues.

The fate of the control equipment on the operator's level and the auxiliary equipment, like AC-DC motor-generators, on the cavernous ground floor remains to be seen, however the safe option would be to leave it in place just in case. Numerous lift bridge have been converted to a fixed status with the counterweights left to dangle for many decades with little thought.

The petition requires a 120 day trial period of being "closed" at which point it will be approved or denied. After that there would be no set timeline for Amtrak to make changes so if a signal move looks likely I'll keep you informed.

THORN Tower's Last Act

Amtrak's THORN tower has been staffed 24/7 and routing trains on the former Pennsylvania Railroad Main Line since 1938, however after having gone on a rather extensive diet in recent years, THORN tower appears to be entering its last act. However its not going without a few strange twists.

As a CTC era tower with both local and remote relay based interlockings, THORN presents a fairly easy case for remote control, as was the case with THORN's sister tower COLA back in 1987. Already Amtrak has chipped away at THORN's territory, re-signaling CALN interlocking and transfering control to the Section C dispatcher in 2020.  Now it appears that the plan is to re-signal and transfer control of the local THORN interlocking in the middle of 2025.  

While this would typically mean the closing of THORN tower itself, the news is that the tower will continue in service controlling GLEN interlocking via the 1938 CTC machine and FRAZER interlocking on the 1994 vintage unit lever panel. Much of THORN's work involves FRAZER interlocking as that is where SEPTA trains for the busy R5 Paoli/Thorndale service lay over.

Plans also include the removal of DOWNS interlocking with deadhead movements continuing on to THORN. For years track #2 between THORN and GLEN had been in terrible shape with Amtrak operators and dispatchers looking for ways to avoid using it.  However it has been recently rehabilitated and train managers are looking to make better use of the asset. 

With these changes I would expect to see "C" boards for Rule 562 operation on both sides of THORN and if DOWNS is removed it is possible that cab signal only operation will extend all the way to FRAZER (track #1) and GLEN (track #4). Whatever happens, I'll keep everyone informed.

PHOTOS: Amtrak CORK Tower

 A while ago I posted the first part of my coverage of the Pennsylvania Railroad's 1929 CORK interlocking tower in Lancaster, PA which covered the tower's history and the layout of the interlocking on the PRR's Main Line. Today we cover the tower itself, heading inside to see how it functioned in both its pre and post re-signaling phases. The exterior photos date from 2005 when the interlocking complex was in the process of being resignaled. 

To recap, CORK interlocking and tower were constructed as part of the 1929 Lancaster station project which moved Lancaster's busy passenger depot away from a downtown alignment with slow speeds, lots of grade crossings and partial street running. The resulting interlocking plant spanned approximately 3.3 miles of main line track, which was an outlier for early 20th century direct wire controlled interlockings in North America. Like the contemporary Lancaster station. CORK was built of a dark brick and featured a prominent bay window sheathed in copper cladding. 

 

 

The tower had one auxiliary building that housed the primary compressed air plant and was situated on the south side of the tracks in line with the extreme west ends of the high level station platforms. The tower had an internal staircase with the shelf type relay room on the first floor. With its brick construction and slate roof, the tower was in excellent physical shape as it entered the 21st century. 

 

Heading inside the tower we find a typical layout with the operator's desk sitting in front of the US&S Model 14 interlocking machine. A defect detector readout and overhead catenary section breaker control panel are to the operator's right with the lockers, clock and old telecom plugboard sitting to the left. One interesting feature is that the room has retained its original 1929 vintage overhead lamp fixtures. 

The operator's space is feels like a more cramped version of HARRIS tower with less space around the interlocking machine on all four sides. The gap between the scoreboard style model board and the rear aligned internal staircase is particularly small. As with other PRR Main Line towers, lever blocking devices are stored on top of the interlocking machine and the bathroom is in the left rear corner. Also note the location of the refrigerator, notice board and train order hoops. 

The sprawling CORK interlocking plant was controlled by a relatively modest 67 lever interlocking machine with 49 active levers in its 1960's configuration consisting of 23 levers for switches, 23 levers for signals, 2 levers for electric switch locks and 1 crossing lever for the Reading's Lancaster Branch diamond crossing. The plant was divided into three timer zones, A, B and C with the A timer handling the Conestoga section, the B timer the central Cork plant and the C timer the Reading crossing. The short run was 1 minute with the long run being about 5 minutes and 30 seconds. The tower also had 4 horns for Conestoga, the tower itself, Lancaster West, Dillersville yard and the Reading crossing (Longs Park).

One interesting feature was the presence of Rusty Rail tabs instead of the more usual placard. Besides that the levers were of the standard US&S crank type.

Although CORK's model board was a standard PRR illuminated type, it had several interesting features features. Grade crossing status lights were located at either end of the board to indicate the activation status of the Irishtown Road (east) or Eby Chiques (west) crossings. There were three low air alarms for East and West Conestoga in addition to the Cork main plant. In the post-1960 era two block indication lamps were added for tracks 1 and 4 eastbound. These had some interaction with PARK tower to the east as well as the intervening temporary block station at LEAMAN with track #1 being lit by the regular 2 lever and track #4 by a button on the operator's desk console. Best I can tell this was some technical method to prevent conflicting movements beyond what would be afforded by train orders and the dispatcher. Finally the most endearing model board feature was a framed photo of CORK tower itself that is also present in photos from c. 1992.