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Saturday, June 14, 2025

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.


Friday, June 6, 2025

Open Railway Map's Signaling Layer is Hot Garbage

Open Railway Map (ORM) is a great resource that recently came on the scene to allow for fast identification and tracing of railway lines, rights of way and even individual tracks. Unfortunately as project that is based in Continental Europe, its coverage of North America (and the British Isles) has some serious shortcomings, especially when it comes to signaling and train protection systems. The information is incomplete and the presentation is seriously lacking. Ironically we have already seen a better way to present this sort of information in multiple railroad-produced employee timetables. 

In Europe almost all railway lines are considered signaled, with the specific method of block working, (ie manual, automatic, token, bi-directional, etc) not being as important as it is in North America. As a result the signaling layer mostly documents special train protection systems like ETCS, TVM420, LZB, etc. (Even then a lot of "National" ATS-like systems like AWS and Le Crocodile do not make an appearance, although PZB does.) 

 

When translated to North America the result is a generic tag for "PTC" and another for "ATC", even though neither labels refer to specific train protection systems as is the case on the European overlays. One might say the project got a little in over its head trying to color code every protection system, although they do have 40 color codes for speeds. The maps cannot seem to handle situations where multiple gauges, electrification systems or train protection systems are present on the same track segment.

The solution, at least for the North American segment, is to first dump the generic "PTC" and replace it with ETMS and ACSES. Next, drop ATC and replace that with Cab Signal System (CSS) and then add in "ETMS with CSS" where applicable. Since ACSES generally needs CSS there is no reason to restate the presence of CSS in that case. For a stretch goal I would add tags for CTC and ABS, however in a global context indicating bi-directionality is less important, so maybe a single TCB tag for "track circuit block" can be used where ETMS is not present. In the (currently) few cases where ETMS s present without TCB, and "ETMS with TWC" tag could be used. 

In an ideal world ORM could "stripe" colors where multiple tags apply in a similar fashion to the Union Pacific employee timetables which at one point were managing CTC, ABS, TWC, ATS, ATC and CSS systems, but that would probably require significant development time.

If ORM had some clear way to make contributions I'd be down to make the more basic changes myself wiki-style, but I can't see exactly how to do that and e-mails are going unanswered. Leave a message in the comments if you know what I'm missing.


Saturday, May 31, 2025

Adios B&O MEXICO Tower

The reason I tend to miss a lot of closures and demolitions is because I don't tend to seek out news that will leave me bummed and depressed. In another example of bad news I missed the B&O's "M" aka MEXICO tower, near Cumberland, MD, was apparently demolished in September of 2023. The three story 1950's brick tower was similar to many across the B&O and, with its CPL bracket masts, had served as a backdrop to the local railfanning scene for decades.

CSX has been engaged in a long term project to convert the former hump classification yard to flat switching and a large obstacle to this was the physical hump and related structures.  MEXICO, built at the same time as the classification infrastructure, was located some 2 miles away at the eastern end of the yard leads and was in good structural condition.  Although its possible that CSX plans to alter the track configuration at MEXICO interlocking at some future date, I suspect that since they had already contracted for the asbestos remediation guys to come out for the yard hump tower, also getting rid of MEXICO could have come with little additional cost. 

Former Cumberland Yard hump infrastructure

Closed as an interlocking station in the mid-1990s, the relay based GRS plant was not re-signaled until the mid-2010's. Unless similar B&O towers at GREENE JCT (boarded up) and PATERSON CREEK (derelict), MEXICO saw use as an active railroad structure, either for maintenance crews or a rest facility for departing road freights.  The implementation of new service plans that generally sidelined the old system of classification yards may have played a role as Cumberland would see less originating eastbound trains and therefore less need for a standing structure to support the crews.

I personally only get to visit the location once on the ground, getting my photos from the road bridge like everyone else, although I had many opportunities for photos from the Capitol Limited with the last occurring in 2019.  Of those B&O towers that still survive, PATTERSON CREEK, only about 4 miles away from MEXICO as the crow flies, would be the most similar example.

Saturday, May 24, 2025

NECR Resignaling Project is Complete

I can report that the re-signaling of the New Englande Centrale's main line that hosts Amtrak's Vermonter north of the Massachusetts border has been completed. While I had previously reported on the state of this project, I can confirm that all legacy signaling has now been replaced. While the diamond at Bellows Falls was perhaps the most visible of the final round of changes, the north end of the Putney siding was also re-signaled. 

As always there are a few interesting details I should point out. The previously reported signaling anomaly at Bellows Falls resulting from a old double to single track conversion, has been eliminated. Trains at Bellows Falls now get a Clear signal indication for a straight route at Wapole siding as opposed to the previous Approach Medium to Medium Clear. 


The holdout signal at SOUTH BELLOWS FALLS has been retained, evidently to allow interchange with the Green Mountain Railroad without needing to seize the main line all the way to Putney.


The entire NECR portion of the line has done away with the Boston and Maine / Guilford practice of ultra-long ABS blocks. Now signal blocks will be a more uniform 2-4 miles which limits the impact of track circuit failures and increases capacity.


Having been re-signaled just prior to the start of the most recent project, the South Putney interlocking will be the only non-standard signal location on the line with a poor man's bracket mast for southbound trains and the use of Safetran scallop shell modules as opposed to Progress Rail square modules.

Although an honorable mention goes to the old northbound searchlight signal on the Bellows Falls platform that was so popular as a photo backdrop. That has been moved to the adjacent park around the Bellows Falls Chamber of Commerce.


It will be interesting to see if this affects on time performance or the schedule at all. In theory replacing the TWC with CTC for the 10 or so miles south of Brattleboro could allow a speed increase.

Friday, May 16, 2025

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.
 

Saturday, May 10, 2025

The Enthusiasts Step Up

Unlike Europe, Heritage railroads in the United States never developed a vintage signaling component beyond what one might describe as display items. The big reason for this is that in service signaling and interlocking appliances have significant regulatory inspection, testing and documentation requirements that are beyond the reach of most tourist train operators. The result has been that most preserved towers are completely inert, with just a handful having interactive elements such as operable interlocking machines (SS43 BERK) or full on simulations (HARRIS). However, in recent years it seems that the private collector/enthusiast space has been stepping up to fill the gap as exemplified by the small YouTube channel Laser 711.

Signal and signaling equipment collectors have been around for some time, snapping up such items as model boards, CTC cabinets, full size signals and even interlocking machines. Until recently, railroad signaling departments would tend to keep their retired equipment, as similar vintage hardware was still broadly in service and the parts to maintain them were no longer being manufactured. However, the PTC related re-signaling push rapidly phased out so much of the relay era railroad signaling that the equipment is now being sold for scrap or offered free to anyone with the capacity to haul it away. 

In the context of interlocking towers, model boards and CTC cabinets have been widely collected for some time as switch to video display in a dispatch office had long ago destroyed their reuse value. Somewhat ironically, it was the older mechanical and electro-mechanical interlocking machines that retained the most value as a source of spares for their kin.  (For example a major reason LENOX tower near St. Louis was closed was to supply parts to the CNW LAKE ST machine in Chicago.) However as the number of these in service interlocking machines hit zero, anyone with a large enough truck could cart the survivors away for their own personal amusement. This is where Laser 711 comes in, having apparently set up not just a HARRIS style PLC backed simulation, but the full hardware stack including relays, point machines and signals.

 He has also restored an ex-Erie CTC console from BK tower along with its original code system, and now appears to be in the process of implementing as much field functionality as possible "in relay".

Of course it would be great if more publically accessible museums were able to step up to the plate with functional period correct signaling equipment, but the signal enthusiast community, powered by recent advances in the "maker" scene and high capacity pickup trucks, seem to be taking up a lot of the slack. Just like we have seen with the extensive telecom switch collection of Step by Step Phil, these private efforts stand a good chance of eventually finding their way into durable preservation.

Attempted CTC at the Seashore Trolley Museum

I will also mention that non-FRA regulated streetcar/transit museums have the best capacity to implement "live" historic signaling. When visiting Shoreline Trolley Museum I was shown their "in-progress" CTC system that they were building from thousands of relays donated by Amtrak and Metro North.

 

The fact that I have not heard much if anything about that project in the past 20 years hints at its priority in the greater scheme of things, but all it takes is the right team of enthusiasts to get a project off the ground.

Wednesday, April 30, 2025

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.