Limited Triangles!

 A little while ago I mentioned NORAC Rule 280b Approach Normal, a signal indication that has been effectively extinct in the wild for over two decades. However we will look at another marker type signal indication that used to be fairly widespread, but as far as I can tell, has now been reduced in the United States to just a pair of locations on the former PRR Main Line. Of course I am referring to the limited speed triangle.

Introduced sometime around the 1940's, the bright yellow Limited Speed Triangle was deployed on speed signaled railroads in conjunction with the introduction of the #20, Limited Speed turnout. For the uninitiated this translates to speeds of about 40-45mph. Prior to this speed signaled railroads tended to have a main line Normal (Maximum Authorized) speed of  50-70mph, a Medium (aka Reduced) speed of 30mph and a Slow speed of 15mph. The system worked from both a track engineering standpoint given the speeds involved and logical standpoint in terms of full speed, half speed and quarter speed. As equipment improved throughout the 1920's and 30's, the gap between the maximum speed trains could regularly achieve and the 30mph Medium Speed began to grow. Because its easier to decrease running time by not going slow as opposed to just going fast, a number of Eastern railroads invented both faster turnouts and the concept of Limited speed. 

#20 Limited Speed turnout at BRYN MAWR interlocking.

Just like in the 1980's when High Speed 60 and 80mph turnouts were invented, railroads suddenly had to fit the round peg of a new speed into the square hole of their existing signaling system. In a time when flashing signal relays were generally shunned as unreliable the solution was the Limited Speed Triangle. The black bordered yellow triangle would upgrade Approach Medium and Medium Clear indications to Approach Limited and Limited Clear. In cases where a #15 turnout was being replaced by a #20, the signaling change would involve change to interlocking wiring or logic. 

Although some railroads including the Reading, did invent new non-flashing limited speed color light signal like Y/G/G or R/G/G, limited speed triangles were embraced by the PRR, B&O, L&N, ACL/SAL and Southern. They also appeared in Canada with the addition of the letter L inside the triangle. Of course one of the biggest users of the triangles was the PRR, which would employ them at select junctions and along its 4 track main lines that features frequent non-reverse running crossover movements.  More specifically the PRR deployed limited speed upgrades (and triangles) to places where its 4-track lines would shift orientation from ⏬⏬⏫⏫ to ⏬⏫⏬⏫ and also as part of its general World War 2 era NEC re-signaling effort.

DV Interlocking with a mix of Limited and Slow speed diverging routes.

Starting in the 1950s flashing signals became more accepted and the Limited Speed Triangle began its slow decline. The main downsides was the inability to mix Limited and Medium speed routes, the issue of Approach Limited indications proceeding Medium Approach and the reduced visibility of the triangle vs a color light, especially at night. By the dawn of 21st century I was only aware of two remaining installations of limited speed triangles. The first was at COUNTY interlocking on Amtrak's NEC in New Brunswick, NJ with a full set of four triangles at the interlocking itself and the milepost 31 and 34 automatic locations adjacent to it. These were unfortunately replaced in the early 2010's as part of the larger 562 re-signaling effort between COUNTY and FAIR near Trenton.

 

The other use of limited speed triangles, and the only one still in service today, were the milepost 8 and 11 automatic signal locations adjacent to BRWN MAWR interlocking on the name brand "Main Line" portion of the Amtrak Harrisburg Line. These two signal locations are adjacent to the Ardmore and Villanova stations respectively and easily photographed. The reason BRWN MAWR itself lacks the triangles is because the tower caught fire in 1994 and the interlocking redone with modern hardware including flashing relays. The two distant locations will certainly keep their triangles until the Main Line between ZOO and PAOLI is slowly re-signaled over the next 10-20 years.

 

Note I have been invoking the United States instead of North America in terms of the endangered nature of these signals.  That is because Canada still retains quite a few of its Limited triangles generally on its western transcontinental routes at the ends of single track passing sidings. Highly ironic that the land that hasn't seen a flashing signal indication it doesn't love, has become the final refuge for a hack intended to avoid flashing signals.

MBTA Re-Signaling Project Reaches Lowell

An update for my previous reports on MBTA's re-signaling efforts on Boston's north side commuter lines.This project consists of installing cab signals and Rule 562 operation on all or part of the North Side lines as well as the general replacement of GRS SA-type searchlight signals. In fall of 2020 the project had already commenced, but there was no sign of it at CPF-BY in Lowell when I stopped by for a visit. 

In fact I even documented ongoing maintenance work on what appeared to be brand new replacement SA heads.

Well recent photos indicate that the re-signaling work has no only reached CPF-BY, but also also replaced the GRA SA searchlight dwarfs with L&W LED searchlight dwarfs, which I guess is better than Safetran cube stacks.

At this point there is no information about CPF-LO, CPF-WA and CPF-NC located beyond the end of MBTA operations at Lowell, but before the end of MBTA ownership at CPF-NC. I suspect this might become a signaling sanctuary as CSX would want to avoid needing to run cab signal or ACSES equipped leaders here and the MBTA would want to hold out for Federal rebuild money to extend service to Nashua.

CPF-NC in late 2021 showing no signs of change.

Additional reports indicate that CSX has dropped new signals at CPF-309 and/or CPF-307 which would be in line with their plans to assimilate the old Guilford territory.  No word if the new signals are CSX standard hoods or Guilford/MBTA targets and also if CSX is planning to run Rule 562 as all Boston Line locomotives will be cab signal equipped and multiple sections of the old Freight Main Line will have MBTA cab signals.

SEPTA Suburban Trolley Signaling: Past and Future

Light rail is currently the locus of signaling innovation in North America due to its mix of limited regulation, low budgets and legacy systems.  For example I have previously written about DART's three different signaling methods in use on its light rail network. In Philadelphia, one such legacy system is the suburban trolley lines running out of  69th Street terminal on the western Philadelphia border. Similar to Pittsburgh's south hills light rail lines in concept, the method of operation is currently being converted from a basic trolley era ABS system, to a hybrid CBTC system.  As I just managed to pick up a bunch of new photos, I figured it was a good time to cover both systems while they are still in the transition period. 

Route 101/102 block signals at 69th St

The ABS system inherited by and later updated by SEPTA as necessary, was a 2-block affair with signals displaying proceed (green) or stop (red). Although there was one location, Drexel Hill Jct, that could be described as an interlocking with full signal protection and a power operated facing point switch, the entirety of the Routes 101 (Media) and 102 (Sharon Hill) were run under traditional ABS rules with hand throw crossovers and spring switches entering sections of single track. 

Two aspect ABS signals at a Route 101 hand throw crossover including operator hut.

 
The single track segments were handled with an automatic tumbledown scheme and the one junction was fitted with a three lamp signal and a route selection punch box. Where a diverging move was encountered a yellow signal indication would be displayed. There was also no ATS or ATC enforcement of signals or speeds. 

Legacy yellow diverging aspect at east end of Route 101 single track segment.

Due to the sections of street running and close spacing of stops, the Suburban trolley LRV's are considered to have sufficient braking performance to dispense with an Approach type indication. Signals are approached prepared to stop and when the next block is cleared, the following movement will get a clear signal to proceed. Not all of the route miles are protected by signal indication with the street running and other slow areas working on sight. These sections are partly defined by "end of block" signs. 

Route 102 switch protection signal paired with a single track block entrance signal.

In addition to the two lamp ABS signals, there are/were switch position indicators and reverse direction protection for the single track sections and Drexel Hill Jct. When entering single track and exit signal would follow the spring switch to protect against a race condition if two opposing trolleys were to attempt to "seize" the single block at the same time. 

Route 101 single track switch signal with block entrance signal in distance.

Starting in 2019 work started on a new CBTC based signal system that would also make use of sizable number of interlockings to replace hand throw crossovers and single track spring switches. As of early 2022 the CBTC system had not yet entered service so the interlockings were used to supplement the existing ABS signal system. 

New SEPTA Suburban Trolley cab display unit with CBTC disengaged.

In fact on the combined section between 69th St and Drexel Hill Jct there were sufficient interlocked crossovers to supplant all of the ABS signal locations! As many of the ABS block signals have so far remained on the routes past Drexel Hill Jct during the transition period, it is anticipated that the CBTC will provide full block separation, not just a safety overlay.

New Route 101/102 combined trunk interlocked crossover and block section signal.

All in all the project involved the addition of 10(!) new interlockings, three crossovers on the combined Rt 101/102 trunk, Drexel Hill Jct, one crossover on each Rt 101/102 branch, three Route 101 single track endpoints and one Route 102 single track endpoint. In addition to these interlockings, three additional holdout signal locations were installed in proximity to an interlocking.

New interlocked holdout signal at entrance to Rt 101 single track territory to accommodate short turns

Another interesting new feature is the provision of a yellow fixed ATS transponder adjacent to each fixed absolute signal.

Yellow ATS transponder located between mast base and rail.

Although I was unable to observe every detail of the current operation it appeared that the new wayside interlocking signals were backwards compatible with the old ABS system displaying R - Stop, G - Clear, Y -Diverge. The presence of a 4th lamp hints at at the presence of a lunar white indication that will either be used for a "cab speed" (most likely) or an absolute block / restricting signal.

Same location as above prior to rebuild with spring switch and yellow "end of block" sign indicating start of line of sight operations.

Although the new CBTC/CTC system is modern and high tech, it never the less exhibits the limits of technology to deliver substantive performance gains. Ten new interlockings along with 20 or so miles of CBTC will cost more to maintain than the legacy ABS system. Furthermore, the speed control function will almost certainly decrease performance from current standards. On the other hand contingency operations will be greatly improved with track work becoming possible during operating hours and vehicle/overhead line failures now able to be worked around without the need for temporary block operators hand throwing switches. In theory the capacity of the system will improve, especially on the route 101/102 combined trunk, however the decision to run more frequent service has always been limited by the budgets and political will of both SEPTA and various levels of government. My assessment is that operations will say the same, liability will decrease along with speed and the impact/cost of contingency operations will decrease enough to offset the high cost of the new signaling system, at least until the point that the technology becomes unreliable.

Death by 1000 Cuts: The NYCT Subway Slowdown

 Starting in the 1990's, the New York City Transit Authority (NYCTA) started a process to slow down the largest subway system in North America, ostensibly in the name of safety. Over the next two decades the process, conducted slowly and out of public view, went from costing riders a few minutes here and there to triggering a full on capacity meltdown as the system, despite its decreased performance, benefited from record ridership. Transit Twitter and Blog personality Uday Schultz has recently completed an exhaustive history of the great slowdown and the science of transit speed control in general. It's a great read and starts with a zero based explanation of the NTCYA's trip-stop and timer based ABS signaling system up through the events that triggered the management action and the subsequent slide into dysfunction. Still, while this piece does a great job explaining why, it comes up a bit short explaining "why". So lets dive in a bit.

One shot GT timer signals added to CANAL ST interlocking before re-signaling.

In the early 2000's everyone in the NYC Subway fan community was aware of the performance decreases and would track how the NYCTA seemed to seek out any location where trains could get moving and just find ways to throttle service back to a plod. Even in locations with no infrastructural changes the trains were operated with an appreciable lack of urgency. The community was full of theories as to why this slowdown was happening and, to a lesser degree, why nobody seemed to care. After all other cities, even those with traditional signaling systems like Philly, Chicago and Boston, found ways to achieve brisk acceleration and top speeds of 55-70mph, making the 25mph crawl of the NYC Subway a distinct outlier. 

SEPTA Broad Street Subway Express train @58mph.

As Uday's article covers (read it now to avoid spoilers), the speculation the early 2000's fan community was both right and wrong at the same time. They were right in that most of their theories were correct.  They were wrong in that there was no one reason that bore primary responsibility for the problem. The newer equipment, up through R68, did have slightly better performance than those the signal system was designed for. The new composite brake shoes did have slightly worse performance than the old iron shoes. The system did rely on train operator rules compliance and related management thereof to ensure safety. Then, between 1991 and 1995 all of these factors combined in varying degrees to cause four significant accidents, opening the NYCTA up to both liability and public pressure.

Inbound Williamsburg Bridge ramp with carlength long grade timer blocks.

The response was similarly multi-pronged from slowing rolling stock down in both acceleration and top speed (55 to 40mph), ubiquitous use of intermittent speed control devices, curtailment of restricted speed operation and harsh punishments for trip stop engagement. Much of this action plan was implemented over a period of 20 years so casual riders didn't really notice the decline in performance. The cherry on top was that the intermittent speed control devices were then allowed to drop below posted thresholds making operators wary of even trying to follow the posted speeds. This is what caused the opportunity to get a skilled operator and a "good run" to vanish over the course of the 2000's, especially as the pre-90's workforce that learned to run trains without speedometers, gradually retired. 

All of this background leads to the real question, why did ostensibly high level management decide that such a drastic decrease in performance was acceptable? This is important because in an age when getting the public to *want* to choose public over private transport, the performance of public transport is increasingly throttled by policy leaving private transport as the only option that can attempt to offer speed and convenience. Well, lets put on our 1991 hats and see what management may have been thinking.

1. The most salient factor was the long term plan to equip the NYC Subway with a full time ATC/ATO system, later realized with the selection of CBTC to replace the wayside signals, timers and trip stops. Investment in an end-of-life signal system would be wasteful and performance decreases could be argued as temporary.
   
   
2. After peaking at 2 billion annual riders in 1948, the shift to non-urban living and private transport dropped ridership by over half with the peak of NYC's crime wave coinciding with the subways trough of ridership. The system was running at half capacity so "slightly" increasing trip times was likely not seen to be a big deal.
   
   
3. Decades of disinvestment had caused the NYC Subway to fall into a prolonged state of bad repair. With limited funds compelled trading performance for safety.
   
   
4. The threat of continued accidents was a political liability while small overall changes in performance would be unlikely to generate much if any notice let alone political pushback.
   
   
5. The reliance on operator skill presented not only the continued risk of accident, but would also put up pressure on costs as said skilled workers had to be trained and retained. Uniform operations according to the speed control systems would make operators fungible and require a lower skill floor.
   

These 5 factors could be arranged multiple ways to create a compelling policy proposal to management. It would have taken an extraordinary amount of personal risk for any of the top officials to insist on maintaining performance standards when CBTC was right around the corner anyway. I think the decisive element was the NYC Subway consistently running at half capacity for over two decades. It's not even that signal system capacity *could* be reduced with little impact, but that the 900 million annual ridership seemed to be both a floor and generally baked into the city. If local New Yorkers were willing to risk their life to ride the system, an extra few minutes wasn't likely to deter them either. To some extent management was proven correct, their slowness campaign only became a problem after ridership doubled over the following 20 years.

If you want a take away its that reducing performance has, is and will be the go-to fix for even rare safety problems. We've seen this with PTC and we've seen this on other transit systems like SEPTA and WMATA. The changes are rarely publicized and the public rarely objects even as they unconsciously sour on rail transit and make the switch to private vehicles. After the service meltdown NYCTA did set up a speed improvement task force that has been fixing the mis-calibrated timers and raising speeds that were subjected to overly conservative calculations. Still, while the rollout of CBTC has allowed for increased performance profiles, it would be interesting to calculate if they match what was achievable by human operators working under a system with a slightly greater tolerance for risk.

PS: An interesting comparison can be had with how the UK responded to the Ladbrook Grove Rail Crash of 1999. The crash program to install TPWS at select locations was similar to NYCT's system-wide modifications, however as far as I can tell, it had minimal impact on train operation, perhaps in part of the UK's continued reliance of train drivers' compliance with rules to ensure safety, as opposed to technical mechanisms.

A History of Amtrak's 562 Distants - From Concept to Removal

It was reported in Railway Age that Amtrak has filed to remove its wayside distant signals installed at 10 locations on the former PRR Main Line (currently referred to as the Harrisburg Line) between Parkesburg and Harrisburg exclusive. While this move caught me completely off guard, I cannot say it is exactly surprising given more recent developments along the line. Amtrak's application is full of appeals to PTC as a rationale, however that's pretty much the regulatory equivalent flattering the teacher. At this I'd typically cut paste a boiler plate plea for people to go out and get their photos while they can along with an assessment of my own ability to get photos (which is pretty good BTW), but instead I will dive a bit deeper on the history of Amtrak using wayside distant signals in cab signal only territory in general and the Harrisburg Line in particular.

Fist of all I want to normalize the use of Rule 562 as the shorthand for "Cab Signals without fixed intermediate wayside signals" method of operation. While this is a NORAC specific rule, cab signal only operation is most closely associated with NORAC and just saying "Rule 562" is a LOT more concise. For those who are unfamiliar, Rule 562 operation it means that between interlockings train movements are governed only be cab signals. At interlockings wayside signals are retained to physically display information for operational efficiency, in case of cab signal failures or other contingencies. There can also be special cab signal realted signal indications to support this operation, most notably the Rule 280a and Rule 280b modifiers "Clear to Next Interlocking" and "Approach Normal".

This method of operation first appeared on the PRR Conemaugh Line in the late 1940's, although a few railroads like the CNW and CNJ also did some 562 experiments about the same time. The method didn't really take off until the 1970's with the Long Island Rail Road and then the 80's with Metro-North, Conrail and Amtrak. Despite not being a NORAC member, Metro-North was the first to really innovate in this space as it looked to do something about the truly ancient signaling it had inherited including copious amount of semaphores. Intermediate wayside signals would be removed, interlockings would have full wayside signals with the "C" board for Rule 280a and wayside distant signals approaching interlockings would also be retained with an "N" board that would display when the "C" was displayed at the interlocking itself.

The process was simple, a train that suffered a cab signal problem would be given the Rule 280a absolute block, "super clear" indications and when approaching the next interlocking it wouldn't even have to slow down provided a Rule 280b was displayed at the distant.  Moreover the wayside distant would provide the necessary speed information for the lined route at the interlocking. Approach Medium with a lit "N" meant the non-cab signaled train would slow for a Medium Speed route with a Rule 280a "C" displayed. Delays would be avoided and all the commuters would get home happy. 

Metro-North reduced aspect wayside signals.

Well it turned out that Metro North found this system to be a bit overkill given the frequency of cab signal failures. They found it to be so unnecessary that they converted to a reduced aspect signaling system with just 3 indications: Stop, Cab Speed and Absolute Block. On the other hand in the early 1990's when Conrail was going all in on the Rule 562 concept, they decided that they liked the additional flexibility of CISC interlocking signals for their unwieldy freight trains, but the Rule 280b concept was a bit too much and wayside signals would appear only at interlockings.

Conrail era 562 territory wayside signal with 'C' marker.

Amtrak's first big foray into Rule 562 was the Shore Line between New Haven and Boston. In conjunction with the 150mph Acela service, the entire route would require a top to bottom re-signaling with Rule 562 as the method of operation chosen for much of it. Perhaps as a reaction to operational problems encountered on Metro North territory, Amtrak decided to install wayside distant signals in advance of its Shore Line interlockings. Although a few instances of Rule 280b "N" boards did appear, they were never placed in service. This brings up the motivation behind the distant signals if they had limited utility in a cab signal failure. Without Rule 280b they would be mainly informational about the state of the route ahead allowing crews to correct mis-routes or employ better train handling than was possible with surprise cab signal drops, especially for freights. For example slowing quickly and then coasting towards a Stop signal in hopes it will clear before a complete stop is required. At worst they might give crews of cab signal failed trains the impression that they did not have to approach the next interlocking prepared to stop (although today ACSES does enforce Rule 280a if cab signals are cut out).

Shore Line Milepost 133 distants with turned 'N' markers.

Amtrak next employed Rule 562 for the high density signaling system used between Newark and New York Penn, but here the nature of high density cab signaling didn't lend itself to the concept of any wayside distant.  Wayside distants did make a second appearance on the ~2005 Harrisburg Line modernization project between PARK and STATE interlockings with a total of 12 wayside distant locations being installed around PARK, LEAMAN, the old CORK complex, RHEEMS , ROY and STATE interlockings. Due to the new PARK interlocking being the boundary between 562 and Rule 251 (ABS) territory, the westbound track #1 562 distant was left bagged for when the re-signaling was expanded. This would turn out to be the last Amtrak Rule 562 distant to go up and one of the first to be removed.

Amtrak's following Rule 562 projects on the NEC, Hudson Line and Springfield Line would all drop wayside distants completely. Back on the Harrisburg Line in 2017, when STATE tower was closed and the interlocking rebuilt for high speed movements, the associated wayside distant at Milepost 101 was quietly removed instead of being altered to display new signal indications. When Rule 562 was extended from PARK to CALN and THORN, the bagged distant at Milepost 44 was also removed. So as 2022 comes to a close, it is clear that Amtrak has passed on the original NORAC Rule 562 concept of wayside distant signals providing seamless recovery from cab signal failures and they have felt this way for some time. 

The affected wayside signal locations on the Harrisburg Line are located at milepost 55.3 (Tk 1&4, LEAMAN wwd), 59.2 (Tk 1&4 LEAMAN ewd), 64.5 (Tk 4 HOLLAND wwd), 66.1 (Tk 1 CONESTOGA wwd), 70.8 (Tk 1 CORK ewd), 71.8 (Tk 2 LIDITZ ewd), 81.5 (Tk 1&2 RHEEMS wwd), 86.0 (Tk 1&2 RHEEMS ewd), 92.3 (Tk 1&2 ROY wwd) and 96.4 (TK 1&2 ROY ewd).  Of these the most notable loss will be the Milepost 59.2 signals located at the old Irishtown Road crossing on an original PRR era overhead signal gantry. 

Still, many of the rest are accessible and also worthy of being documented so get out there over the next year while the wheels of regulatory approval turn.

The LIRR's Puzzling ESA PTC Waiver

As the opening day of the Long Island Rail Road's decades long East Side Access mega project approached there appeared a new hiccup. Apparently the ESA tunnels were not built to support some of the LIRR's diesel rolling stock that routinely runs to New York Penn Station. Setting aside how the LIRR managed to make their brand new tunnel more restrictive that what it typically the gold standard in limited clearance, someone somewhere noticed that a mis-routing could do a can opened job on an oversize train and demanded that the LIRR perform some mitigation. 

Reverse switch to remove roof.

The typical way one would accomplish this would be to have a system of interlocked high car detectors. Tripping a detector would immediately cancel the route and the train would be stopped via both the Cab Signal ATC and ACSES PTC systems. What was so baffling about the LIRR's PTC waiver request was that they were trying to install a new "Tunnel Collision Avoidance" capability to ACSES that would allow for a positive stop at a non-absolute signal or signal indication point. The ACSES positive stop system functions via a transponder telling the on board system to enforce a positive stop in X feet if no cab signal code or radio release is received. This feature was expanded to also cover trains without functioning CSS getting a positive stop at an absolute signal not displaying Rule 280a "Clear to Next Interlocking". TCA would likely work in the same way with a transponder setting up a "positive stop unless" condition combined with a high car detector linked radio release or a cab signal code being present. In fact I think it is actually the latter because part of the aforementioned waiver notes that the ESA tunnels all use only the 250hz cab signal carrier frequency and overheight equipment (DE/.DM30's with C3 coaches) cannot detect the 250hz carrier at all. (See note below)

So my reaction to this is why the heck is the LIRR scrambling to modify ACSES when this was seemingly a solved problem. The fact a waiver is being applied for at all answers part of my question as this must have become an issue only after all of the HAROLD design and signaling work was specified and completed. My Spidey sense tells me that the LIRR's original solution was the use of the 250hz CSS carrier that would drop the cab signals of Amtrak, Metro-North and DE/DM stock to Restricting, at which point the engineer would stop the train short of the low tunnel. Regardless, the Powers That Be demanded a positive stop and instead of adding a new absolute signal at the tunnel mouths, the LIRR decided to do a software fix. I can see how trying to add an HCD system to HAROLD could result in a lot of costly testing given the number of potential routes involved. (After all, the cost of testing prevented NS from even changing the Conrail era HCD recording at CP-BANKS until the general re-signaling project in 2018!), but a couple of extra holdout signals seem pretty straightforward. Based on the general discourse of NYC project management, I suspect the cost of constructing even something "simple" in New York City made a signal-vendor supplied software fix the "better" option.

Before I wrap this up I want to complete the NYC-Region trifecta of poor public sector planning, high cost and political posturing by pointing out the letter that accompanies the FRA's granting of the rather short term PTC waiver. With everything the LIRR is doing to prevent mis-routes including route-indicating signals, rulebook rules, locked out routes, ATC enforced 15mph speeds and the 250hz fail safe cab signal code trick, I would have expected the FRA to issue a letter that states something on the order of "you have gone above and beyond to mitigate this problem".  Instead the letter goes on at length about how everything I mentioned is somehow deficient and they reluctantly approve of the waiver. Here's an example.

"The Board also shares Brotherhood of Railway Signalmen’s concerns about LIRR’s existing hazard detection system not protecting Amtrak trains operating in the Harold Interlocking from being misrouted to the GCM tunnel. FRA notes, however, that if an Amtrak train operating with oversized rolling stock is routed towards the GCM tunnel, a series of redundant protections exist to prevent that train from entering the tunnel. First, if a route into the tunnel is incorrectly lined so that an Amtrak train with oversized rolling stock is lined for movement into the tunnel, the train’s PTC system will enforce a positive stop at either signal 11W or 65W. To proceed past either of those stop signals, the train engineer would have to obtain dispatcher permission to by-pass the PTC enforcement and would be held to a PTC enforced 15 miles per hour (mph) speed limit. Second, as a train approaches the signals and diverging switch that controls the tunnel entry track, the train crew will see routing arrows on the mast of the relevant interlocking signals (up to three signals in advance), which will illuminate white when a route is lined from any of the tracks to the GCM tunnel (the arrows will not illuminate if the track is not lined for the tunnel entrance). This will provide Amtrak train crews the opportunity to stop their train, as required by Amtrak’s special instructions. Third, in the event an oversized train passes the 11W or 65W signals because of human error or a failure of the PTC system, and the train crew does not notice the illuminated arrows and take appropriate action if they are operating an oversized train, LIRR’s cab signaling and ATC systems will protect the Amtrak train, as it would any oversized LIRR train, through the 250 Hz cab signal code which will provide an audible alarm and enforce restricted speed."

  If you don't want to read all that I can summarize in a 14 second video clip.

What's even more telling is that its the railroad signaling union that is explicitly complaining about the lack of TCA capacity. Just remember, whenever a Union is applying political pressure there is likely overtime to be had. Now, the Railroad Safety Board is a political entity and they are going to do whatever they can to cover their asses to the max and/or avoid political problems with unions that might still provide a few Democratic votes, but the waiver also includes at least 6 safety theatre-esque action items that will add more time and cost to the entire ESA enterprise. Is a mis-route possible? Absolutely, they happen all the time.Even with all the protections could we actually get the can-opener effect? Well an Amtrak Keystone did go to Cynwyd 🤷. Still, the likelihood of all these Swiss cheese holes lining up is remote, especially as there are countless locations along busy passenger tracks where a bad route can take a train into a yard or an out of service track and they aren't causing major safety problems. If rail is every going to deliver nice things, we can't have this level of of CYA virtue signaling coming from the top.

PS: The entire docket of documents related to this waiver, including that super useful HAROLD interlocking diagram, can be found here.

*Note: The PRR legacy Cab Signal System as now deployed in North America makes use of code rates in pulses per minute and one or more AC carrier frequencies in cycles per second (hertz). These can be combined to increase the number of usable codes if so desired. Railroads on Amtrak's Northeast Corridor make use of a 100hz carrier for the basic CSS codes and a 250hz carrier for additional codes that were added ~1999. The LIRR uses an expanded set of pulse code rates and therefore does not need a secondary frequency. This means they could make the EMU stock (M3's, M7's and M9's) sensitive to both a 100hz and 250hz carrier with the same code rates. All other equipment including Amtrak, Metro-North and DE/DM stock will receive a Restricting cab signal in the abstinence of a 100hz code.

NEW LIRR Front End Videos and News

The (temporary?) return of Budd M3 Metropolitans to LIRR service has resulted in a bevy of head end railfan window videos from Youtuber Mr Master 767 including the new Main Line third track arrangement between DIVIDE and QUEENS interlockings. I figured I would post some of the videos and then provide some quick commentary on the key points of interest.

On the Ronkonkoma to NY Penn segment above we can see the final result of both the Ronkonkoma double track and Main Line Third track projects. The good news is that BETH and both core and extended parts of DIVIDE interlocking remain position lit, however the new MNRR style reduced aspect signals have taken over all other portions of the route to QUEENS interlocking.  At this point QUEENS is scheduled for additional re-signaling and re-configuration with BETH and DIVIDE to follow in subsequent years unless the MTA's financial situation heads this off.

In the above Atlantic Branch video we can see that DUNTON interlocking is still largely position lit, but point machines are now electric.  VAN interlocking has also been converted to electric, but BROOK appears to be holding on with some remaining pneumatic. 

On the Long Branch Branch LEAD interlocking has been converted to non-reduced color light (probably several years ago), no word on the status of LEAD as a manned interlocking station however.

Finally on the Port Washington Branch a reconfiguration of NECK interlocking appears ready to see the replacement of multiple position light masts, gantries and pedestal signals including the practically brand new westbound signal bridge. This is accessible from the station and is definitely on my To Do list.

New Amtrak CPL Just Dropped

As previously covered, Amtrak has been adding new high level platforms to Penn Station Baltimore in support of a redevelopment effort. While my initial focus was on the loss of pneumatic point machines at PAUL interlocking, another side effect is perhaps more interesting.  The new platform has resulted in the, at least temporary, removal of the southbound mid-platform PRR pedestal equipped cantilever signal at PAUL interlocking on track #7 where the former 'F' storage track merges in. The expected replacement would have been to move both pedestal signals to ground  mounted locations, but for whatever reason (lack of clearance?) Amtrak got creative and used a B&O Style CPL dwarf instead.

The B&O CPL dwarf is not only in the NORAC rulebook (largely due to DC Union Station), but also covers all the signal indications that Amtrak would need at this location. The previous cantilever signal was installed with the NECIP project that closed UNION and B&P JCT towers and upgraded the slow speed, doubleslip heavy PRR era mixed traffic terminal with a higher speed passenger oriented layout. Later a second pedestal cantilever would be installed at CHARLES for low level track #3.

CHARLES interlocking features an intermediate signal on track #7 (7SA) so the 7S signal on the cantilever could be observed displaying Approach Slow for a Slow Approach at 7SA for a Stop at CHARLES Baltimore tunnel exit signal 7SB. Although the capability for Approach Slow on the CPL was retained, I was only able to observe the signal moving from Stop and Proceed to Slow Approach to Clear, possibly due to how the other signals were being fleeted.

Slow Approach appears to have replaced straight Approach on the 7S. This seems logical given the short signaling distance, although it may have required also modifying the 1S signal a PAUL and/or 1S signal at BIDDLE.

I will make a point to return and make more observations to more accurately determine the changes.  It also remains to be seen if this is a permanent arrangement or if the cantilever or ground mounted 7S pedestal will return. The switch in the middle of the track 7 platform occasionally causes operational headaches, especially with a positive stop requirement and if money/space is available, extending track F several more car-lengths would likely present the best solution.  

Fire at POND Tower

I have received reports that the former LIRR POND tower has suffered a fire related incident.  The extent of the damage is currently unknown, but the wooden structure would be highly vulnerable to flame.  POND is located on the LIRR Montauk Branch at the west end of Fresh Pond Yard, which now serves as the base of operations for the New York and Atlantic and, by extension, rail freight for the entirety of Long and Royal islands.

Built in 1905, POND was on the LIRR end of the junction with the New Haven / New York Connecting RR's freight extension to Bay Ridge via the Hell Gate Bridge. Closed as an active interlocking station at some point in the 70's or 80's, POND outlasted its newer and more robust sibling FREEMONT tower on the Bay Ridge Branch by being repurposed as the NY&A's freight/yard office. It's location in an isolated and wooded area probably meant that transient related vandalism was inevetable.  Hopefully the damage is such that repair, rather than demolition will be warranted, but I am not optimistic.  

The Has-Been Returns

About a decade ago a superb signaling related blog run by a retired US&S signal engineer came to my attention.Titled The Has Been, the site was self-hosted and used dynamic IP address services making it almost completely invisible to the wide world of Google searching. Unfortunately, after a few months it made a switch to a new dynamic DNS service and because I was not in "the loop" the site effectivly went poof.

Well thanks to some new friends I have been made aware that the site still exists, obtained a stable DNS entry and has been updating regularly over the past decade. The site is still not searchable on any public search service and has several other internal features to prevent automated scraping. However it does contain a keyword search and an archive that is served up by calendar month. I figure I am going to have my hands full catching up on all of the great signaling content I have missed. Anyway the current URL is thehasbeen.org:9090, enjoy!

 

Fort Worth Tower 55 Facing Demolition

In a huge surprise it seems that Fort Worth's iconic TOWER 55 is under threat of immediate demolition with work to begin on Monday, November 14th. A report went out on Twitter, but the planned date was pushed back. 

The iconic railroad interlocking Tower 55 in Ft. Worth is being demolished today noooooooo 😭

RIP King pic.twitter.com/PBr9gWMfm7

— Metalheadrailfan 🎅 (@metalheadrailf1)

As we have seen with demolition efforts with AR and MG towers near Altoona there are numerous factors that could yet scuttle the demolition plans, including detection of hazardous substances like lead or asbestos. It is also unknown if the tower will need to be gutted first or simply demolished as-is.

TOWER 55 is located in downtown Fort Worth and consists of a3x2 diamond crossing between two major Union Pacific main line with connecting tracks on all four quadrants. The junction is so complex that it has its own signal committee posting handy "you are here" signs. It is on the order of such towers as SANTA FE JCT in Kansas City or F TOWER in Fostoria.

The tower checks none of the boxes of demolition risk. It's made of brick, in very good condition with modern windows on the operator's level.  It is located in a quadrant of the jct behind a fence line and is used by local MoW or C&S crews. The most likely explanations are some sort of spite (aka "cost cutting") or a need to expand the east-west line from 2 tracks to 3, which could require running the new track through the tower's footprint.  If anyone knows anything more specific or has updates about TOWER 55 please leave them in the comments.

K TOWER "Relocated" w/ N-X Panel Retired

It has been confirmed that Amtrak has relocated the train director(s) working K TOWER at Washington Union Terminal from the historic 1908 structure and into a small office in the Railway Express building adjacent to Track 29 on Union Station's lower level.

 

Unlike R Tower in Sunnyside yard, where a similar relocation immediately preceded demolition to make way for an Acela maintenance facility, the historical significance of Washington's K TOWER is well understood.  In 2017 I reported on plans to cover over the entire union station approach with some mixed use development with K Tower specifically singled out for conversion into some sort of high end bar. The culprit here is some combination of Amtrak's desire to simplify "management" and also cut costs along with some technical upgrades that were evidently completed behind the scenes.

As constructed in 1908, Washington Terminal was controlled by at least three US&S Electro-Pneumatic equipped towers, A Cabin, C Tower and K Tower. In the 1970's, K Tower had its long Electro-Pneumatic machine replaced with a then cutting edge N-X type interface and model board that drastically cut the need for staffing (and floor space) and centralized control of the entire terminal into a single location. This change likely took place around 1975 as the construction of the DC Metro's Red Line required the demolition of C Tower. Although cutting edge for the 1970's, by the 2010's the N-X machine was becoming increasingly difficult to maintain as parts were long out of production and failures could become rather nail biting in terms of getting the machine working again.

Although decorated with some LCD screens, the big old N-X panel's days were numbered and as soon as the control was converted into a video display interface, the human train director was no longer limited to being in the tower itself, especially if CCTV feeds could be provided. Although I suspect the historic K TOWER will be maintained and serve a railroad function, while active as a work site the HVAC, restrooms, etc would all need to be maintained to a higher standard. Plus there is the added benefit of management being able to "pop in" to "supervise". It is quite possible that the N-X panel was actually replaced years ago and COVID simply delayed the inevitable. K Tower would therefore be a rather extreme example of a "return to the office" policy. Still, given that computers can be installed anywhere, there is always the chance that the K TOWER staff could find themselves back in the old tower in the future, baring some redevelopment effort.

K TOWER joins the fate of many other pre-video "panel" type interlocking setups that I discussed previously in the content of Hoboken's rather short lived TERMINAL TOWER. Given the ease at which an N-X panel can be converted to a video interface, it is entirely possible that, rapid transit systems not withstanding, we  might see electro-mechanical machines outlast hard wired N-X panels in staffed towers.

Baltimore Power Director's Office to be "Preserved"

 More details are emerging about the fate of the Power Director's Office in Baltimore Penn Station. The entire 1911 station building is undergoing a major restoration with the upper floors slated to be turned into office space.  Unfortunately the Power Director's Office, located in room 222, is included in the redevelopment plan and will be cleared of all the PRR era 25hz railroad electrification control equipment that has remained in place since the office was closed in the mid-1980's when CTEC took over.

The less bad news is that some portion of the equipment including at least the large display board, will be relocated to a more public part of the station. A local TV newscast got a tour of the office and according to their report this new location appears to be in the 1911 building where the current ticket and baggage rooms are now. (Those facilities will be moving to a new station building across the tracks). It is unclear if all of the equipment, including 1940's based telecom gear for the SCADA functionality, will be moved or just the visually interesting conversation pieces. Also being lost is the physical character/ergonomics of the current Room 222 space and any support infrastructure like cable ducts and light fixtures.

As I previously reported, Amtrak recently leased the former Harrisburg power office to the Harrisburg Chapter NRHS for preservation and it currently shares the second floor of Harrisburg's Penn Station with a number of third party offices. Other shuttered offices still exist at 30th St station and the New York Penn Station support building.