Search This Blog

Sunday, November 30, 2014

Harrisburg Line Trip Report

Over the weekend of November 8-9 Amtrak ran its fall Foliage Train on a round trip over the NS Harrisburg Line from Philadelphia to Harrisburg and I was able to use the trip as an opportunity to check up on the state of signaling on the line.  For those of you who don't know the majority of the Harrisburg Line comprises the former Reading Railroad Main Line to Reading and then the Lebanon Valley branch to Harrisburg.  Although it has seen a fair bit of re-signaling over the years, it still retains a good deal of its original Conrail signaling.

Leaving Philly the 1990's era Conrail signals at CP-PARK, CP-BELMONT, CP-RIVER and CP-FALLS are all still in place, but the Reading brackets next to I-76 have been replaced and CP-ROCK has been re-signaled along with some of the ABS signals between there CP-NORRIS

No straight route on Track 2 at CP-NORRIS indicates Rule 251 Country
There were still quite a few Conrail style small-target searchlight signals between CP-ROCK and CP-PHOENIX, but nearly all of the ones between there and CP-BIRD have been converted into single direction NS style Darth Vaders.  Of course this really isn't news as these signals were installed starting in 2006!

Surviving Harrisburg Line small target Searchlight.

 One major issue with Rule 251 operation emerged when needing to run under a Form D from CP-TITUS to CP-PHOENIX our train was forced to run at Restricted speed for 4 miles because the reverse direction signal only supported Stop and Restricting and with no exit signal we had to travel through the very long CP-PHOENIX and then the block beyond it under a Restricting indication.

New signals, old indications.
CP-BIRD has of course long been re-signaled and BIRD tower demolished, however Conrail style US&S NR color lights are still in place between CP-BIRD and CP-TITUS.  CP-TITUS, which in Reading days was a flat 2x2 diverging 251 junction still retains much of its original configuration and I believe its original signal logic and pole lines.  One special treat is the movable point diamond, a real rarity in North American flat junctions which prefer crossings that can double as crossovers.  On the other hand, the Reading Belt Line's CP-CRUMU has been completely re-signaled.

The Reading downtown WYE retains all its Conrail updated Reading signaling including CP-CENTER.  Also the line between there and CP-WYOMISSING JCT is still operated under Rule 251.

The Harrisburg Line between Reading and Harrisburg was one of NS's first major re-signaling projects right after the Conrail merger and involved replacement of the Rule 251 system with full CTC and crossovers due to the 50+ trains a day that the line sees.  This uses the short-lived NS standard of non-Darth traffic light signals and the special "crankable" signal masts where the heads could be lowered via cable for maintenance.  That practice did not catch on and has since been abandoned.  The old CP-TARA retains its original Conrail signals, with everything else being NS Vintage.  At Harrisburg the Reading vintage CAPITOL tower remains standing. 

There is a bit of news at the Rockville Bridge wye in that aside from the new Darth Vader mast for the yard lead exit at CP-ROCKVILLE, the pneumatic switches at CP-WYE have recently been converted to electric, I suspect along with CP-HIP across the river.

CP-WYE, 2006
Finally I did have some time to do some recon on the Buffalo Line.  Photos showing that CP-SOUTH FERRY had had its signals replaced alarmed me, however I discovered that CP-NORTH FERRY retained its PRR PLs and both end of the MILLER siding not only retained their PL's but had also seen some refurbishment akin to the surviving Port Road signals.  Even CP-SOUTH FERRY retained its original 1950's CTC relay hut and potentially its signaling logic.


Tuesday, November 25, 2014

Where Old Signals Go to Live On

When railroads retire signals they are typically thrown in the scrap heap, sold off to railfans or sent down to the C&S shoppe to keep any of their surviving kin up and running.  For the general public the best they can hope is that a few of the signals will reemerge in someone's back yard or in a static display at a museum.  After all, what other use is a railroad signal than railroad signaling? with everything in life there is a loophole to every rule.

Every so often a railroad will recycle its discarded signaling apparatus until the less vital world of grade crossing warning devices.  After all a flashing light is a flashing light.  This can give life to signals far beyond their typical sell by date.  Perhaps one of the more (in)famous examples are track circuit fed warning lamps placed at a number of N&W private crossings in West Virgina.  These used surplus N&W amber PL-2 position light signals as track occupancy lights that extinguish when the circuit is shunted by an approaching train in the block.

Now I know some of you might be saying that I am cheating as those PL marker lamps may have been installed new, instead of used, but in a related use case the Cape May Seashore Line has employed surplus PL-3 lamps as so called "snitch lights" on its rather unreliable grade crossing equipment as seen in this 2005 photo.

Look above the crossing flashers for the amber light.
A few months ago I came upon another recycled railroad signal in grade crossing service while documenting SEPTA's FORD interlocking on its Norristown Line.  A twin stack of GRS model FA modular drawf signals had been mounted low down on a vintage cantilever flasher mount at the Ford Street (Of course!) grade crossing. 

The extra pair of flashers had been installed because cars pulled up to the crossing would not be otherwise able to see the flashers above them.

 When the signaling department (either SEPTA or Reading) needed this supplemental hardware they went to the recycle bin instead of the PennDoT catalogue.

Check out that hexagonal charm
Perhaps the ultimate example of old signals living on in crossing applications is the B&O's reuse of semaphore signals as pedestrian crossing gate mechanisms.  I first noticed this phenomena while passing through Cumberland, MD on Amtrak's Capitol Limited and like the SEPTA signals above I did a double take as I was confronted with railroad signaling in a place I had not expected to see it.

Unfortunately the Cumberland examples were replaced before I could get good photos of them (how many times can a signal be replaced?), but fortunately I know of at least one other example of this type of signal reuse and it is transit accessible!

At the famous SEPTA Route 11 - CSX Philly Sub grade crossing, a pair of former B&O semaphores stand guard on the sidewalks stopping cyclists and pedestrians from crossing the tracks.   

 I wasn't joking.  The B&O (or Chessie System) literally replaced the semaphore blade with a red and white striped crossing gate and put it into service.

These are 90% as "good" as a in service signaling semaphore.  The train approaches the semaphore drops, the train leaves it goes back up again.  All that's missing is the / position so just pretend you're in manual block territory. 

Combine the semaphore crossing gates with old school cantilever flasher masts, frequent trolleys rumbling over an active railroad main line and a nearby B&O CPL signaled interlocking and you have perhaps the most interesting level crossing in the country.

Thursday, November 20, 2014

CTA Mini-Towers

The Chicago Transit Authority has remained a strong supporter of the "tower" system of rail transportation control.  Just like the NYC Subway and the Long Island Rail Road, the CTA's traffic density still gives an edge to human eyes and judgement in place of automated routing and remote control.  Those who ride the CTA are probably aware of the currently manned towers placed at the yards and major junctions.  It is pretty hard to miss them the way the operator's cabs typically cantilever out over the tracks.

The CTA even produced this video showing its recently rehabilitated towers at TOWER 18 and CLARK JCT, which received brand new NX Panels.

However the CTA has another type of tower, one  that is almost ubiquitous, but also hard to spot.  While local control panels are a common feature in most relay rooms, the CTA steps things up one notch by placing many of these, from junctions to simple crossovers, in their own little booths.

 The most "tower" like of these mini-towers is TOWER 12 at the southeast corner of the loop where Orange and Green line trains split off to the south.  While this junction is normally remote to Tower 18, there is still a small porta-potty sized booth where a human operator takes over at peak periods.

Another form of the CTA "mini-tower" is a space built right into the trackside relay huts.  Again the giveaway are the windows placed in a manner that would allow an operator full view of arriving trains.

Here is a portable interlocking cabin set up at the Harlem and Lake Green Line terminal and again the small window for manned operation is present (also note the interlocking horn).

Finally, sometimes the operator can get his own stand-alone booth on the station platform.  One such mini-tower is located at the south end of the Damien Blue Line platform.

This mini-tower controls a small scissors crossover immediately behind it.

The interlocking is clearly remote from somewhere else, but as you can see the Damien local tower has a fully functional panel.

 It has NX buttons for the signals as well as overrides to throw the switches without a signaled route.  It also has buttons for the direction of traffic on all four exits, call-on buttons and even a button to sound the interlocking horn.  Of course there are switches to set control local, remote or automatic.

What's interesting and a touch ironic is that at the opposite end of the same platform is a classic style tower that was built, but never placed in service as the junction it was to control was eliminated.  It looks like the CTA took a second bite at the apple. :-)

Tuesday, November 11, 2014

Better Know a Signaling System - Seaboard

Well last time around we explored the signaling system that ate the Northeast.  Now we can explore the signaling system that is eating the signaling system that ate the Northeast. The Seaboard Coast Line railroad, itself an intermodal amalgam of the Atlantic Coast Line and Seaboard Airline, is the 'S' in CSX and the Seaboard system of signals are those which CSX has chosen to standardize on, brushing away the B&O CPLs, C&O color lights and former Conrail NORAC signals.  The reasons is not really due to any inherent superiority, but has more to do with major flaws in both the C&O and B&O systems and the company headquarters being in Jacksonville, FL and NORAC signals were not invented there.  Note I am not going to call these CSX signals because there is still little that CSX has had to do with them, unlike NORAC, which may have borrowed most of the signal rules, but still put its own stamp on them.

Unlike the other dominant signaling system in the South used by the Southern Railway, Seaboard uses speed signals and today is one of the three major codes of speed signaling code along side NORAC and CROR (Canadian signals).  It shares a lot in common with those other codes including the three head (Normal, Medium, Slow) system and Y/G for Approach Medium.  However Seaboard is defined more by its differences than its similarities.

Seaboard's most defining characteristic is its use of Lunar White and only Lunar White for restricting.  There are a few smaller route signaling systems that have this feature, but ever since the availability of *R*, no other major railroad has relied on just Lunar White. 

Back when the Seaboard adopted Lunar for Restricting, Restricting was a seldom used indication, mostly seen where there were routed leading to unsignaled track like yards.  For normal interlockings the Seaboard did not provide any capability to display a "call-on" and therefore they made do with US&S N-3 and 3-color searchlight heads.  However in modern times it is CSX's policy to provide a restricting capability on all controlled signals.  This in turn leads to the frequent use of 4-lamp signal heads, which were nearly unheard of in the area of searchlights and pre-cast color light heads. 

The use of LW for Restricting of course frees up R/Y and R/R/Y for Medium Approach and Slow Approach respectively.  R/Y/R is also used for Medium Approach and is employed by CSX in areas where conversion from non-Seaboard signaling is under way (Conrail, RF&P, P&LE, Etc) or a third signal head is provided.  Lunar white is the first of many instances where CSX management has said "my way or the highway" when its comes to incorporating the signaling ideas of others.  CSX predecessors NORAC, P&LE, RF&P and the C&O all used lower yellow Restricting, which has the advantage of not needing 4-lamp heads, but I guess the south is always right.

 Now just because one had R/Y for Medium Approach doesn't mean that R/*Y* can go unused.  CSX has decided to fill this slot with Limited Approach, which appears to violate the principle of reducing trains to Medium Speed upon passing an Approach indication

Seaboard's other fateful decision was the continued use of Y/Y advance approach, even where the aforementioned alternate speed signal systems had switched over to Y/Y for Approach Slow.  The real kicker is that CSX does not currently use the *Y* aspect, even as an alternate Advance Approach for NORAC compatibility.  This requires that all "patch jobs" require an extra signal head instead of just a flasher relay.  Now if you look closely at the 1989 CSX signal rules I posted above *Y* is listed an a Y/Y alternative, but the original Seaboard set did not include this option and CSX itself later dropped it as well for reasons unknown.
One such patch job on the Abbeville Sub in Bogart, Georgia where three additional signaling locations needed to be modified with extra heads due to a new short block.

 Without a two lamp Approach Slow indication like Y/Y, all situations involving Slow Speed must use "three headed monsters" to display the Y/R/G flavor.

Like several other pre-NORAC railroads (and the C&O) the Seaboard used R/Y/G for Medium Approach Slow for reasons involving one block sidings that I have already explained.  However CSX chose not to update R/Y/G to the now more common Medium Approach Medium when that indication was added in the 1990s, instead flashing the lower green up "upgrade" the older indication.  If you jump ahead to 6:17 in the following video you can see a CSX medium Approach Medium leading to a R/Y Medium Approach.

In the theoretically sound Caltrain speed signaling system R/Y/Y was chosen as Medium Approach Slow as it worked off the Y/Y/R approach slow and R/Y/G Medium Approach Medium.  Without Y/Y Approach Slow or R/Y/G Medium Approach Medium, Seaboard used R/Y/Y for Medium Advance Approach.  I suspect this might be the rarest signal indication of the Seaboard set as I have yet to positively identify a high signal location where it is employed.

Note: Do not mistake C&O Medium Approach for Seaboard Medium Advance Approach as both use R/Y/Y, but the former is much more common.  C&O signals will be covered later.

Dwarf signals are fairly typical of a speed signaling system with the major exception of Y being Slow Approach instead of Restricting.  The necessity of lunar has made the 4-light Safetrain Unilens dwarf units very popular with CSX.  Here is one displaying the Y/R variety of Slow Approach.

As one might expect R/Y and R/G are Medium Approach and Medium Clear respectively, the latter being perhaps the one case where Seaboard scores a point over NORAC.   One can tell  if a Seaboard dwarf stack protects a medium or slow speed turnout based on the position of the green lamp relative to the red. R/*Y* is provided for Limited Approach, however because of Y/R/G Approach Slow, there is no dwarf version of that indication available. 

 One might expect dwarf Y/Y to be used to the fairly common Advance Approach indication, but, bafflingly is used for Medium Advance Approach.  Unlike using Medium Approach as a Substitute for the missing dwarf Approach indication, a quirk Seaboard shares with NORAC, using Medium Advance Approach would require trains to slow to medium speed first leaving Approach Medium as the short block speed control alternative.

That's pretty much all there is to the Seaboard system of signaling.  It's a solid set of speed signal aspects, but unfortunately was never able to evolve past some of the depricated practices like Y/Y Advance Approach or R/Y/G Medium Approach Slow.  It's a real shame that CSX didn't use the Conrail merger to, at the very least, (re)adopt *Y* as an alternate Advance Approach.