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Tuesday, July 30, 2013

PHOTOS: ZOO Interlocking Part 1 - The New K

For those of you who didn't know, the famous ZOO Tower (with its formerly 230 lever Model-14 power frame) is is in the news again with the final pair of doubleslip switched in the "K" ladder getting replaced by a standard type turnout ladder.  I still need some time to gather some photos to cover this change, but this also happens to be the 4th anniversary of the "K" section of ZOO interlocking getting transferred to SEPTA so I figured I might as well begin with some additional context.  This will be the first of what will probably be many parts covering both ZOO tower and ZOO interlocking.

While originally part of the Pennsylvania Railroad K funneled trains to the upper level of 30th Street Station. In fact Milepost 0 of the famed PRR Main Line is at the end of the platform at the downtown Suburban Station Since the 70's these trains have all been commuter lines run by SEPTA. SEPTA owned trackage starts at the eastern limits of ZOO interlocking and the old K section of ZOO handles only SEPTA movements. While most movements are straight rail through K movements out of the west end of  Powlerton Yard and any special circumstances for trains coming out of SEPTA territory involve special handling. Since SEPTA closed the old PRR BROAD tower and centralized dispatch functions communications with ZOO have become more complicated and for a while after BROAD closed in 2003 misroutes were somewhat common and once I had to be "sent round the Berry" when my Trenton train came out track 4 instead of track 3 w/o ZOO being notified. 

Both Amtrak and SEPTA found this arrangement irritating as Amtrak disliked being responsible for tracks that doesn't handle any of its trains and SEPTA for having to hear Amtrak complain about this and refusing to put in any capitol investment (the tracks through there have grown extremely bumpy). SEPTA finally found 5 million dollars to re-signal and re-build this section of ZOO as the new K interlocking, controlled by dispatchers at SEPTA HQ and all through 2008 and early 2009 they went about implementing the project.
The old "K Tower" section, named for one of the 4 towers closed in the 1934 ZOO consolidation, is being transfered to the local commuter rail authority SEPTA. Shown in the upper corners here and here the K section consisted of the 25, 27, 39, 45, 47 and 53 turnouts and 28, 30, 32, 40, 42 and 168 signals. One very surprising development is that the 64 signals and 65 switch (seen here) were included in the re-working. This means that Amtrak will have to get permission from the SEPTA dispatcher for trains entering or leaving the Rundown track to Amtrak's own M of W yard. The Cuttover is scheduled for midnight on Saturday morning so if anyone has time they should go ride SEPTA today to take some final pics of the remaining old hardware. 

Anyway, back in2007 I was expecting the worst when it came to the re-signaling of K with its PRR amber position lights and pneumatic point machines. I was hoping they would leave the signals in situ and just re-wire them, but I was in for a pleasant surprise as SEPTA decided to install brand new LED Amber PRR Position Lights. Here are some early pictures I found on

Since US&S PL-3's aren't made any more the signals were Safetran units and the new point machines were  electric. SEPTA also installed new Amber PL's at ARSENAL interlocking so unlike the turncoat LIRR there seems to be someone cool working in the C&S department at SEPTA

Anyway, for your reference I have posted a PDF of the Bulletin order describing the change.

The cutover was a rather slow motion affair with new signals and switches put in place, but wired to the big Model 14 machine in ZOO. This has provided the opportunity for ZOO to have one last hurrah controlling some brand new signals.On a 2009 trip on Amtrak's Pennsylvanian I managed to take a number of the ZOO-attached new signals.

Here's a new Cantilever with the old 30R and 32R signals for 3 and 4 track westbound.

The big signal gantry with the old 40R and 42R signals on track 1 and 2 westbound.

Big gantry with the 181 and 182 exit signals as well as the to-be-removed 32L signal. It's interesting to note that many of the new signals show more aspects than their former counterparts. 181 and 182, for example, both have new lower heads.

The same thing applies to the 183 and 184 exit autos show here in 2012.

Another view from K showing the classic wide signal gantry with the 181 and 182 exit autos and a much improved trackbed.

Saturday, July 27, 2013

PHOTOS: LIRR VALLEY Interlocking and Tower

VALLEY interlocking in Valley Stream, NY on the Long Island Rail Road (of iced tea fame) is one of the more important and visible towers on the LIRR. It was re-signaled in 2009 or 2010, but due to the LIRR's commitment to service quality the tower repained open converted from its original 1930's US&S Model 14 interlocking machine to new panel and video game setup. The tower is located at the quintuple junction(!) of the Montauk Branch, Long Beach Branch, Far Rockaway Branch, West Hempstead Branch and Atlantic Branch.

Now I don't have as many details as I usually do due to the retaliative opacity into LIRR operations as the labour organization is skilled at protecting the jobs of its workers, however some of the photos I have were made available by a knowledgeable individual on one of the forum's I frequent. Despite the LIRR prefix VALLEY and almost all the rest of the classic LIRR physical plant this was essentially a PRR operation as the LIRR was a wholly owned PRR subsidiary up until the mid 1960's when it was given over to the Metropolitan Transportation Authority. The tower is typical for late 1920's PRR interlocking plant with all brick construction, pneumatic switches and of course position light signals, one of which is seen here displaying a Clear indication for a move eastbound to Long Beach on the 24L signal.

Here is a side view of the tower from the Far Rockaway branch showing the air drying unit and a signal from the LIRR thanking you for riding.  Unlike many other PRR towers VALLEY lacks a bay window, but being situated in the middle of the interlocking plant VALLEY tower doesn't exactly need one.

In this view of the model board you can see VALLEY is arranged into West and East sections on what appears to be a 4-track main line.  However the 4-tracks are actually two parallel two track lines with the northern set being the Montauk Branch and the southern set the Long Beach Branch. The single island platform for the Valley Stream station serves the Long Beach tracks and also features a two track flat junction complete with diamond to the Far Rockaway Branch.  This reflects the LIRR's concept of segmented service allowing Montauk/Babylon trains to run express on their own tracks while Long Beach / Far Rockaway trains make local stops.

Despite the 2x2 setup VALLEY is not inflexible with a trailing ladder in the west end to allow any eastbound trains to access the Valley Stream station and Far Rockaway / Long Beach branches.  In the east end of the plant there is a facing point ladder to allow trains to access the West Hempstead branch.  Today this is a minor branch line reduced from a double to a single track junction and non-peak service consists of shuttle trains originating from Valley Stream, laying over in the siding track east of the tower.   This requires shuttles to tie up the entire plant crossing over the 4 main line tracks. As one might expect peak period trains do not attempt to stop at Valley Stream and use the express track to Jamaica.

There is a third section to the interlocking plant which consists of an independent crossover on the Far Rock branch to allow trains leaving or arriving at the island platform to use either Far Rockaway track in combination with any platform track.  Both the Far Rock and Long Branch are run under single direction cab signals without fixed wayside signals, although manual block signals are provided for wrong direction running.

The heart of VALLEY is a US&S Model 14 electro-pneumatic interlocking machine dating from the 1930 when this part of the LIRR was grade seperated. The machine appears to be a 34 lever frame with only about 3-4 spare spaces.   Running against typical standards the signal levers are painted black and the switch levers are painted red.  The interlocking mahcine itself has been painted a pleasant green color which is common practice on the MTA owned NYC Transit Authority.

Unlike later Model 14 setups this one relies on a large number of glass globe signal rundown timers.  This shows the wealth of the PRR since in most interlocking plants poorer railroads would only provide about 1 to 3 timers for the full compliment of signals.  Here the PRR provides a timer for what is presumably every signal pair.  Similar arrangements could be found at OVERBROOK and NORTH PHILADELPHIA towers.  In the 1930's US&S began to offer timers integrated into the Model 14 itself that would cover multiple signals. The new arrangement was not as flexible this one, but offered savings that not even the PRR could turn down.

Here is the original westbound PRR position light signal guarding the west end crossovers and trailing ladder.

Here is the westernmost signal gantry showing the eastbound signals.  While the two primary eastbound tracks are provided with high PRR Pl signals, the reverse direction track on the Atlantic Branch is provided with a dwarf PL reflecting the original single direction operation.  The Montauk was upgraded for full bi-directional operations with the inclusion of a PRR pedestal signal.

Thursday, July 18, 2013

CP Searchlight Mystery Continued

I got some interesting feedback on my post regarding the strange new type of searchlight signal that is now being installed on select new interlockings on the Canadian Pacific rail system on both sides of the border.  To summarize it appeared that CP was installing some new type of searchlight that had a custom housing and mystery interior which could include either a classic searchlight mechanism or something more modern like a Unilens.  The housing was quite a bit larger than the standard old GRS SA style which lead me to believe that the interior was also non-standard.  However I got an e-mail from John Ryan with his own theory on the matter.
"After looking at the the photos showing the new signals illuminated, the uneven nature of the lighting screams incandescent optics. This leads me to believe that CP hasn't invested thousands of R&D hours in some sort of new technology. After all, if they had, the result sucks. Why spend money for no improvement and why spend money on a technology with a limited lifespan?

This is GRS territory. Why not stick with what they have and what the maintainers already support? If you compare photos of the side of one of the new housings to those of any other GRS SA, you will see an identical triangular ratio between the door hinge pin, the mount hinge pin, and the mech mounting stud. Their wire-coupling assembly on the bottom of the housing, retained by three bolts, also looks like it would be a drop-in replacement for the GRS part. Almost certainly there is an SA mechanism in that box. Therefore the guts aren't news, the housing is the Main Event here.

What's so special about the housing? It is NEW. I have a little passel of captive dwarf signals and over time I've taken each of them apart for restoration. There is very little that can go wrong with an H or H-2 housing and the H-5 is the Cadillac of searchlight housings. However, the mid-to-late era SAs have a primary design weakness in the mech rail. The door latch pulls on a loop on the end of the mech rail. Over-tightening, common on heads with failing gaskets, results in the latch pull snapping off the end of the mech rail. Replacing the mech rail forces a confrontation with the bolts that retain the mech rail and the sighting device. I've never successfully removed those bolts without shearing or deforming the stamped bolt end inside the mech rail. Ironically it is easier to remove these bolts from cast housings, as every single aluminum housing has exhibited an aggressive galvanic reaction between those parts. I've scrapped a signal head where the aluminum was so pitted that water was seeping into the housing.

In the course of restoring one of my SAs it was necessary to re-tap the housing and make new bolts on the lathe. That's too much work. If I were running a signal shop and someone brought me a pile of SA heads and asked me to refurbish them to new, I would be very thankful for the near-term job security. I would be busy for a while.

Analysis: CP has shelves of serviceable SA mechanisms sitting around that represent a significant investment. Why not put them to work? The SA housing is flawed, so it is easier to send the critical dimensions to a fabrication house, where the contractor can CAD, stamp, mill, and weld a product far cheaper than an in-house recycling project, and for the equivalent cost of new housings from Alstom. Alstom doesn't want the business anyway; why else would they price the SA into extinction?

What won't break? The door latch. What isn't rotting? The door seal. What isn't leaking? Bolts on the top of the housing, certainly replaced by welds inside and out. What is back in productive use? SA mechs.

Time will tell if this is a successful experiment. The serial number would lead one to believe that they have made at least 623 of them. CP walked away from over 100 searchlights and searchlight mechanisms when they abandoned the Chalk River and portions of the North Bay Subdivisions in 2011. Perhaps that is also a sign that they have more than enough spares stockpiled to last until they are done with searchlights.

As an aside, if someone wanted to design a drop-in SA replacement with no moving parts, they could simply replace the mechanism with a disc carrying a multi-aspect LED diode array. The outer doublet lens would have to be discarded and replaced with plexiglass. If a replacement required focused optics, a solution could be engineered by a team of three in under a week. It would feature three compact LED clusters feeding into a prism. The optics would be mounted in a dummy frame that slid into the mech rail, aligned on the mounting pins, and lever-locked in a secure position. Nothing complicated there, but it is far cheaper to buy a stock colorlight head and bulldoze all the rusty old fossils. The real problem is the neglect suffered by the old equipment, which sometimes exacerbated the design flaws. Time will tell if these new searchlight housings fare any better, but I commend CP for trying. For now it seems to be an improvement on the SA housing. Too bad it is so ugly."
 Well there you have it.  There is a good chance that inside these new housings are classic old GRS electro-mechanical searchlights.  John said he'd ask around and try to get some confirmation on his theories and when/if I hear more I will update this post.  Unfortunately CP is increasingly abandoning the whole searchlight motif on its former D&H and CP main lines, even the Unilens and LED type.  Here's to them learning to change their errant ways.

Tuesday, July 9, 2013

+1 Active Towers: CSX St Joseph's River Bridge

It's always nice when I "discover" a new active interlocking tower and unlike the last time it is still in service, although not in its classic configuration.  The tower I am speaking of is a bridge cabin controlling the St Joseph's River movable bridge in St. Joseph's, MI on the CSX Grand Rapids Sub. For those not familiar with the CSX system this is the route of Amtrak's Pere Marquette train service.  Now unlike most movable bridge cabins which are staffed by a "tender" job and do not control over switches or signals, St Joseph's River Bridge is staffed by an operator who does control local switches and signals.  The bridge is manned 24/7 during the boating months, closing the bridge for train movements and opening it back up again when the train has passed.  As recently as 2010 the actual "cabin" structure was mounted on the swing span itself.  Here is a video of the operator getting out to hand up a freight pickup order to passing local freight Q327, providing a little human touch for something that normally has to be carried out over the radio.

At this time the Cabin not only controlled local signals and a pair of derails, but also an honest to god turnout at the west end of a signaled siding that ran all the way to Riverside, MI.  Such a configuration is reminiscent of the BRIELLE Movable Bridge on the NJT Coast Line.  Here is the original configuration of the east end of the bridge.

Unfortunately such good things never last and probably due to having to either staff the tower in the winter or not have trains able to use the siding, CSX reconfigured the interlocking splitting off the turnout into its own Brenton Harbor interlocking about half a mile to the east.

The operator was taken off the swing span and placed in a brand new interlocking cabin just to the west of the bridge.  It is a blue box structure with a detatched porta-potty, parking lot and air conditioning.  Here is a close-up view of the new tower showing off its street address of 100 Vine St.

Here is a wider view of the "tower" showing the operator's vehicle and the new Darth Vader type signals.  Not sure what sort of interlocking machine is provided, but its probably some panel type unit that incorporates the bridge controls. No doubt some ancient motor control system was also replaced when the interlocking was re-signaled.

While the number of active towers continues to fall and those with traditional machines are almost non-existent, there are a few more towers out there than is known about in the typical circles.  I have been tracking them down by searching employee timetables and the like, but only the long defunct Conrail was nice enough to explicitly note manned towers so sometimes it takes a bit of inference.  Research continues, but I have tentatively identified two local control operators on NS, one in Princeton, IN and another in their Kansas City Terminal.