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Tuesday, July 31, 2018

Liverpool Lime Street Signalbox Closed

One of the last two active Westinghouse Brake and Saxby Signal Company power frames on British Rail was taken out of service on July 13th and it was quite an impressive example, controlling the 13 track stub terminal in Liverpool, England since 1948.  This matters because the WB&S Co Style L power frame installed in Liverpool Lime Street is pretty much a US&S Model 14 just with the levers rotated 90 degrees to moved in the proper British fashion.  Also the all brick structure with a bay window follows the pattern of high quality North American towers as seen on the Pennsylvania Railroad or New York Central.

With 86 active levers and a plant that had pretty much remained untouched since the signalbox was constructed after The War, this is a huge loss for living signaling history, although a number of these frames survive in various preserved forms.

The machine was shut down track by track instead of a simultaneous cutover.  This resulted in the unfontunate side effect of the model board being completely painted over aside from the last two active tracks along the bottom :-( All of this can actually be scene along with general tidbits about the Signalbox's history and future use in this video produced by Network Rail.

Unlike many other British towers Lime St is a listed building and should be preserved along with the rest of the station. Also make sure you check out the The Westinghouse Brake & Signal Company Ltd. Miniature power lever frame website for more information on this cross pond cousin.

Wednesday, July 25, 2018

2018 RF&P / A-Line / H-Line / Southern Main Line Trip Report

It has been three years since I last surveyed the RF&P, A-Line and Southern Main Line and quite a bit has changed. This report will try and cover more of the signaling related changes and less of the various capacity improvements that have occurred in tandem. On the RF&P third track projects are causing intermittent layout changes north of Fredericksburg, but a number of legacy 2 track bridges are isolating the new segments. Not much of a signaling change as the whole area was re-done between 2012 and 2014. South of Fredericksburg a few remaining RF&P large target US&S N-3 intermediates still stand along with the classic bracket mast at Doswell. Towers at Fredericksburg, Millford, Doswell and Greendale were also still standing.

Still hanging in there!

Acca Yard in Richmond has seen major changes. Previously both ends of the yard had been completely interlocked. Now the throats had been converted to hand operation with simplier terminal interlockings constructed farther out. On the south end the old AY interlocking has been relocated with a access cutting through the wye to allow northbound movements off the Belt Line to access all the yead tracks. South of Richmond AF interlocking was getting a complete set of limited speed crossovers to replace a single trailing 15mph crossover. The Petersburg Station has also been provided with a new interlocking to reduce the need for trains to cross passengers across an active main track.

This RF&P vintage modern style N-3 gantry is a goner :-(

South of Petersburg the only remaining classic signals are at CHARLIE BAKER interlocking in Rocky Mount. A few new limited speed crossovers have also been installed with a few extra miles of double track to reduce time spent waiting in sidings for meets which is what eliminated the last few N-3 holdouts after 2015. The NS H-line has also seen a number of improvements with new interlockings and new passing sidings, but the line had already been assimilated by NS so there wasn't anything to be lost. The new Raleigh Station is open, but not all the tracks are in service and there is still work to be done before the new terminal interlockings are fully in service.

The last A-Line N-3s were replaced by new crossovers.

On the Southern main line a smattering of interlockings remain unresignaled, typically 1990's builds with the traffic light style heads. One example is FAWELL interlocking south of Lynchburg. Also, CR TOWER interlocking in Alexandria, VA has seen new Darth heads placed on the Southern vintage ladder poles. Although there are some exceptions, NS did not use the opportunity to add new CTC features such as a Restricting indication into single track territory. This has been done on some NS lines like the former NKP route, I believe, but not Southern. Also, many of the old Southern signal gantries have been left in place along the RoW where it was somehow inconvenient to have them scrapped. So there might be something worth taking a picture of if anyone makes a signal trek.

Apt that FAWELL interlocking would be resistant to change.

All in all this was a pretty dull trip, signaling wise. Exactly what we have to look forward to across North America for probably the rest of time :-(

Saturday, July 14, 2018

Caught on Camera: Clear to Next Interlocking

Also known as NOARC Rule 280a, this special cab signal related signal was invented by the Pennsylvania Railroad for their experimental trial of cab signals without fixed automatic signals (today known as Rule 562) on the Conemaugh Line between CP-CONPIT and CP-KISKI back in the late 1940's or early 1950's.  Without wayside intermediate signals, trains that experience a cab signal failure en route would not be able to proceed without absolute block protection ahead.  Normally this would involve train orders (or today a track warrant/Form D) however the reliability focused PRR decided to automate the potentially delay inducing procedure with a special signal that would illuminate when the track was clear to the next interlocking where the next wayside signal would be located.

 One option could have been to simply display a Rule 280 "Clear Block" signal, which was an upper head | with a single marker below and used in manual block territory.  However because of the lack of manual block distant signals and because of the non-lack of train detection, a new Rule 280a was created, "Clear to Next Interlocking" and it would consist of a flashing lunar white market offset to the side and labeled with a reflective 'C'.  Any diverging movements through the first interlocking would be covered by the fixed signal and trains would be instructed to approach the next interlocking prepared to stop.  Here we can see an example of a Rule 280a being displayed along side an Approach signal at Amtrak's REA interlocking.

As you can see, the 'C' lamp is displayed independently if absolute block conditions are met.  On unit lever and VDU interfaces the 'C' lamp is a separate switch associated with each signal.  While technically unnecessary at back-to-back interlockings, 'C' boards are more often deployed uniformly so crews do not loose track of which signals they can pass with failed cab signals. In this more elaborate demonstration of signal progressions at Amtrak's HUDSON interlocking we can see how the 'C' lamp is placed on the fame flashing circuit as other flashing signals such as Cab Speed and Approach Limited.

Finally, we actually have an example of a display 'C' signal in the wild.  This was at the re-signaled STELL interlocking for a southbound movement against the flow of traffic on the NS Enola Branch.  NS has decided to employ waysideless operation on much of it's cab signaled PRR territory, following in the footsteps of Conrail in the 1990's.  Previously the Enola Branch had been run under single direction Rule 251, but when the line was re-signaled, the Rule 562 operation saved a bit of money on intermediate signals.  First note the NS style backings on the 'C' boards, a practice not carried forward to subsequent projects. Second this is an interesting occurrence as a train with failed cabs could in theory be swapped out at Enola yard and finally note the slower flashing cadence compared with the Amtrak signals.

That's it for this episode of Caught on Camera. Nothing is scheduled for the next time cause I won't know it until I catch it ;-)

Sunday, July 8, 2018

2018 PRR Main Line Trip Report

So it's been a year since my last comprehensive PRR Main Line trip report and a lot has changed in that time. First and foremost, NS's slow and steady re-signaling campaign has made a massive jump westward with new signals now going up along the entire western slope all the way to Pittsburgh on the Pittsburgh Line and Rochester on the Fort Wayne Line. This is a recent development and some of the masts in the Pittsburgh area are still sitting on the ground, however this marks the beginning of the end of the last great position lit terminal on a Class 1 railroad.

Twilight of the PLs at CP-PITT
In a small silver lining it appears that NS is expanding it's cab signaling to cover the Pittsburgh Gap between CP-EAST PITT and CP-KISKI on the Pittsburgh and Conemaugh Lines and CP-ROCHESTER on the Fort Wayne Line. All the new signals are going up with Rule 280a 'C' boards. This would mark a rare modern occurrence of a freight railroad installing a new safety system on it's own accord as the PTC mandate did quite a bit to forestall additional cab signal. Of course this will definitely ruin some of the aesthetics of the 3-4 track freight raceway between Pittsburgh and Rochester, however only about 3-4 automatic signal locations will be impacted.

It also appears that the former ALTO tower territory, resignaled in 2012, will not be getting Rule 280a 'C' boards, continuing to operate under Rule 261 with a single automatic on #2 track adjacent CP-HOMER. Other areas with back-to-back interlockings, like the Pittsburgh terminal, go not appear to be getting the same treatment despite the presence of some shortline operators that would need to get their engines cab signal equipped. NS is potentially increasing the number of signal blocks as the RoW has sprouted numerous new relay huts in odd locations, but these could just be for grade crossings or other secondary functions.

This new signal bridge is here to stay.  The westbound one will be replaced.

On the pneumatic front the entire Middle Division has been changed to electric M23 point machines. Over the hill CP-MG and CP-SO have both lost their pneumatic plants while CP-AR, CP-UN and CP-MO still retain them. West of Johnstown CP-CONPIT, CP-RAGE, CP-TRAFF, CP-WING and CP-HOME are still pneumatic, but will likely be converted soon. Interestingly, CP-C shows no work whatsoever in either the point machines or signals.

Missed my chance to take photos of the pneumatics at CP-SO and CP-MG :-(

In Pittsburgh specifically, signals will no longer play a role in protecting trains approaching the 20mph curve west of the downtown station. Instead of an Approach Medium -> Approach Slow -> Slow Clear (removed) progression, non-diveging trains will get Clear straight through. However the closely spaced interlockings will result in the use of R/R/*Y* Slow Approach signals. Also because the old Pitt signaled siding was removed, the new westbound signal at CP-PITT will only slow straight route signals and Restricting.

In the future trains through Pittsburgh will proceed on straight Clear signals.
While I have been able to document a lot of the infrastructure on this line before the charges started, I can't get to it all, so once again I am urging anyone nearby to get as many photos as you can before the past is gone for good :-(