Ghosts of Union Pacific Cab Signals

Until recently Union Pacific operated one of the most extensive systems of cab signaled main line in North American, if not the most extensive (by route miles). Unfortunately as previously covered, the UP Automatic Cab Signal system was not immediately applicable to informing the required PTC overlay like Norfolk Southern's has proven to be, so the decision was made to take it out of service on at least the eastern portion of the network. However because so many UP locomotives were cab signal equipped and because in most situations the cab signal codes are still active in the rails themselves, UP has taken to covering over the cab signal display unit in the cabs.

I assume the same will be seen on many of the cab signal equipped CSX locomotives now that they have managed to rid themselves of the requirement on the centrally located RF&P Sub. It will be interesting to see how long this setup hangs around before the ACS display is completely removed.

Washington Union Station CPLs go LED

It appears that the next step in Amtrak's surprising B&O CPL renaissance is the upgrade of those in the Washington Union Terminal area to use LED lamps. Since the terminal area was last re-signaled, the US&S built dwarf CPL's have suffered from low output, possibly lower than the more typical GRS counterparts (US&S was awarded the contract and had to make its own copycat B&O style CPL's as a result). Combined with the overhead catenary, it has made capturing signaling indications on camera rather challenging.

Well now things are on easy mode as you can see here with the incandescent pole pointed 315 signal compared with the gantry mounted 311 and 351 signals displaying Clear and Approach respectively.

For another point of comparison here is the incandescent 189 signal displaying Slow Clear at the end of Track #23.

In addition to the LED's we can see that the orbitals on the gantry mounted signals have received new extra wide backing plates, even if the additional orbital lamps aren't installed. Hopefully the LED conversion won't be limited to just the overhead signals, which do suffer from the extra visibility problems caused by the overhead wires..

PU Tower Restoration Update

Former Central RR of New Jersey PU (Phillipsburg Union) tower in Phillipsburg, NJ recently held an open house to shot off the state of the tower's restoration effort. It is affiliated with the NJ Transportation Heritage Museum that, amoung other artifacts, has an operable triple expansion steam pump. I had last visited the tower in 2017 where it was clear that a lot of work had already been carried out, however the Model 14 interlocking machine was a long way from being restored due to massive stripping as you can see below.

I found some photos from the event and starting on the operator's level the Model 14 has recovered a significant amount of levers. We can also see wires indicating plans to reactivate some functionality.

The operator's desk now hosts all sorts of artifacts.

The lower level features a full suite of air compressors and the power board.

 There is also some documentation discussing how the tower was closed and reopened several times by the CNJ as is desperately tried to abandon its operations in PA. I definitely need to get up there again, but I might want to pace myself and wait until more of the Model 14 is functional, just to avoid having to make extra trips. 

SEPTA Broad St Subway Signal Project

The SEPTA Broad Street Line is notable for being one of the best examples of pneumatically powered signaling appliances in the form of point machines and trip stops. The whole line is equipped with such devices except for the Fern Rock shop and yard complex, which was subjected to a re-signaling project around 2005. Well I just caught word that due to a long term plan to rebuild the City Hall station, SEPTA will be installing bi-directional signaling between the line's WALNUT and FAIRMOUNT interlockings.

Single direction signaling at WALNUT interlocking.

Since it was constructed in the late 1928 it has operated almost entirely with single direction ABS with a few isolated segments of bi-directional signaling within interlocking limits. SEPTA's plans to rebuild City Hall will take entire platforms out of service so the usual practice of closing either the local or express track will not be an option. As a result SEPTA is looking to install some bi-directional capability so the normally 4-track railroad can operate as a two track railroad between Walnut Locust and Girard stations. 

It will be interesting to see what brand of signaling equipment SEPTA decides to go with and if they stick with pneumatic trip stops or convert to electric. After the MFL was re-signaled around 2000, SEPTA was able to bank a large amount of 1980's vintage pneumatic trips and A-10 point machines that have been slowly appearing on the BSL so there might be enough in stock to supply the project. Since the wayside signal system is likely to be replaced around when new rolling stock is purchased, this would save money on an ultimately short term change. On the other hand if someone else is paying, SEPTA could decide to rid themselves of a "troublesome" technology. There could also be a mix with the existing equipment left alone and only the new reverse direction signals getting electric. Regardless, I think I might take the time to get photos of whatever is currently in place.

Southern Caltrain Signaling Changes

With Caltrain's new electrification set to kick off soon, I have been checking if there have been any additional signaling changes beyond the removal of the King St Terminal cantilever. While most of the action is happening north of San Jose Diridon, the wires do extend down to the Tamien Station, which has a direct VTA connection and has always seen a bit of through service. Here is what I found when I checked in on the Southern Pacific era signaling on that part of the line.

First up was CP-CAHILL and the southern end of the Diridon terminal. As expected these were replaced some time ago, getting the traffic light treatment in early 2017.

Next were the SP signals at CP-DELMAS about a mile to the south These lasted quite a bit longer, being replaced by US&S modular traffic lights around 2021-2022.

The most interesting changes occurred at CP-MACK at the Tamien Station. CP-MACK had southbound Sp masts, a northbound Sp cantilever and a northbound two "head", 6-module dwarf stack. Around 2021 the track two cantilever signal was changed from SP to Darth Vader type. Then later in 2022, both cantilever signals were replaced by two "head" LED searchlights. 

In an even more baffling turn of events the dwarf stack was replaced by a two "head" mini transit style signals. 

Your guess is as good as mine as to why, but its definitely something to see. As for the rest of the line to Gilroy and beyond, it appears to be unchanged.

RF&P Cab Signals Out of Serice Mid-June

When CSX first announced in plan to discontinue cab signal rules on the RF&P in 2021 I went into some detail about the possible motivations. A year later when the FRA petition was approved (despite a national spotlight on rail safety issues) I again explored some possible timelines for the process. Well it seems that we have our answer and the cab signal system will be taken out of service on June 15th, 2024. 

As a result of the process, I had to assume the worst and I embarked on a program to document the remaining RF&P intermediate signals that somehow survived the great 2010's re-signaling effort. Between 2023 and 2024 I didn't notice any changes on the physical plant so it appears that so far the discontinuation of the CSS has consisted of adding the PTC integration to all of the intermediate signal locations and hand throw switches. Because CSX does not use large visible antennas at every signal location, the process was largely invisible to outside observers. 

What this means on a technical level is that for the near term the cab signal codes will still be present in the rails to transmit block state. CSX in its filings indicated that moving to ETMS PTC for ABS speed enforcement will allow it to remove the mid-block code change points where Approach drops to Restricting. Since these are all less than 10 years old and theoretically reliable, it will be interesting to see if this is given any sort of priority. It will also be interesting to see if VRE has to retain the cab signals on its locomotives for the Washington Terminal area, which I heard is planning to actually install cab signaling in the 1st Street tunnels between CP-VIRGINIA and A interlocking. With VRE looking to purchase the Manassas Line, who knows, CSS might make a return. 

PS: Also keep an eye on the patches of former Conrail/PRR cab signaling around Philly. CSX does not have to run equipped locomotives on this territory so they might keep it active for the benefit of NS.

NJT's Speed Enforcement System: A Thing That Existed

You might have heard me reference the Northeast's preferred transponder based PTC system ACSES, or the Advanced Civil Speed Enforcement System. In most cases when something called itself "Advanced" its usually a bit of marketing speak, but in this case the basic Speed Enforcement System was a thing that actually existed for a brief period of time on New Jersey Transit's Pascack Valley Line. However because of the rapid pivot to more "Advanced" systems and the 2008 PTC mandate, information on the SES pilot is remarkably hard to come by, however I have been able to piece together a few bits of information that can hopefully shed some light on the technology.

In 1996 NJT suffered its worst accident as of the time of this writing when two trains collated at WEST END interlocking where the diesel Bergen County and Main Lines diverge from the electrified Morris and Essex lines. The cause was a veteran engineer who had been hiding a medical condition that had severely impacted his visual acuity mistaking a Stop signal for a R/R/Y Restricting. In the aftermath NJT began an effort to implement what they called "Positive Train Stop" functionality across its system, which came on the heels of a near system-wide adoption of cab signals and automatic train control (ATC). At the same time Amtrak was completing implementation of its ACSES speed control and PTC system on parts of the NEC in conjunction with the new 150mph Acela rollout. This is where things get a bit murky, but going into the 2000's, both Amtrak and NJT had two different yet compatible transponder systems for "civil" (aka track) speed control, however Amtrak "Advanced" system was integrated with cab signals where as NJT left SES as an intermittent system.

The location for NJT's SES pilot was the Pascack Valley Line, a stepchild service that ran some 30 miles north from the old Erie Main Line to dip its toe into New York State. The single track line offered only weekday single direction peak service and, like the similar old Boonton Line, the PVL was essentially unre-signaled since the Erie days. This signaling came in the form of an Automatic Permissive Block-like bi-directional ABS with occasional non-number plated (ie absolute) automatic signals that would have once appeared at the ends of hand operated passing sidings. Without any actual interlockings and only a single block of cab signaling on approach to Pascack Jct, the limited service PVL was an ideal test bed. 

 

Reading through the SES special instructions in a 2004 NJT Employee Timetable (posted below) we can gain some insight into how the system worked. The evidence points towards SES was an intermittent transponder based system that would convey track speed information in a manner compatible with Amtrak's ACSES, but also fixed signal indications. A positive stop was enforced for Stop, Stop and Proceed and Restricting indications, with the positive stop zone extending 500 feet in advance of the signal. Stop and Proceed, and Restricting could then be passed after an acknowledgement, while Stop needed the dispatcher to provide a numerical override code in addition to the verbal Rule 241 instructions. This would have come into play at the non-plated automatics and the home signal at Pascack Jct. Special instructions about cab signal upgrades and other rules not applying in SES territory further strengthen the intermittent use case. 

 

This of course begs the question about how the system would account for signal upgrades after passing an Approach signal if the associated transponder flags a positive stop point like it does in ACSES. As easy solution would be to place additional active transponder at the start of the stop zone 500 feet from each signal, but I have nothing to confirm this theory. An additional feature of the PVL that made it attractive for the SES pilot and that was the presence of signal overlaps. From what I can tell from 2007 era photos, each set of ABS signals had several car lengths between them which would provide sufficient distance for a train running at reduced speed to get stopped before it might encounter an obstruction. This would explain why the SES stop zone is 500 feet vs 1500 for the ACES zone.

PVL automatic signal location with overlap in 2007 with what might be SES transponders (or grade crossing impedance bonds).

SES was always intended to be a temporary pilot and by 2002 NJT had let a contract for its own Advanced SES that integrated cab signals similar to Amtrak, but without the finicky data radio capability for temporary speed restrictions and stop release. Interestingly the $2 million contract with Union Switch and Signal would have outfitted the entire NJT system with PTS and track speed control by 2008! The wireless data free ASES vs off the shelf ACSES debate would extend into the post-2008 PTC era with the ASES plans eventually morphing into ACSES, but perhaps the original SES hints at what NJT's solution would have looked like. Version 1 ACSES also lacked data radios and needed temporary physical transponders for TSR's and use of the stop release procedure to pass certain signals with a proceed indication. Active SES-style transponder could have solved some of those issues without wireless data.

Unfortunately I have been unable to determine the exact timeline of the ABS SES system on the PVL. I know it was in service in 2004 with the CNJ vintage GP40PH locomotives operating in a dedicated pool. I know that SES was still in service as of Jan 1, 2006, however by the fall of 2007, the line had been re-signaled with Rule 562 cab signaling and upgraded with passing sidings to allow for all-day bi-directional service. Unfortunately, starting in August 2006, all PVL physical characteristics and rule changes were put into a separate supplementary bulletin order that I do not have any examples of. Interestingly, the 300 section of NJT special instructions covering SES were left in place with slight modifications likely to cover the upcoming ASES or ACSES installations due to the 2008 PTC mandate probably resulting in some savings in crew re-training. 

If anyone has any additional information on NJT's SES please let me know so I can update this post or make a new one. I've heard a bunch of other stories regarding issues with hair trigger penalty brake applications, but not much more than anecdotes and speculation.