Caught on Camera: PORTAL's new "Gantrylever" Under Test

Following up on the previous post regarding the new PORTAL bridge cutover, Amtrak I happened to catch a cab speed indication on the (New) PORTAL interlocking's westbound cantilever mast's 3W signal. With the new track #3 still very much under construction, crews were getting a jump on commissioning* the new interlockings associated with the project. Although this is a static image, the 3W was displaying a flashing green cab speed indication, which would be in line with the high density cab signaling in place between HUDSON and A interlocking at Penn Station. 

That alone is interesting, but if you review the track and signal diagram from Bulletin Order establishing OLD PORTAL and OLD SWIFT interlockings you might notice that future PORTAL is intended to be laid out similarly to OLD PORTAL with center Track A merging into tracks 2 and 3. Instead in the photo we see a two track cantilever mast, or do we?

Amtrak is splitting the commissioning of the new Portal fixed bridge into two month-long work sessions spaced 6 months apart. The primary reason for this is that activating the new eastbound track #2 will require the prior removal of overhead catenary supports required for both existing tracks. A secondary reason is that the new track 2 will require partly burying the old track 3 and removing the westbound cantilever as you can see below. 

If you look closely the end of the cantilever arm has some extra bits and the diagonal supports at the corner seem a bit flimsy. This is because that new signal structure is not a cantilever, but half of a three track signal gantry that will be completed once its southern foundation has something to sit on. I'd call this a "gantrylever", but that term is somewhat taken by gantry+cantilever combinations as seen at UNION and DUNTON. 

 In other news related to PORTAL's signaling  the lower heads on the westbound signals are conforming to the new pattern established at LEGGETT interlocking on the Hellgate Line, replacing the central lunar white Stop and Proceed dot with a a lunar white Restricting \. However the eastbound signal masts retain the Stop and Proceed dot. This might be a quirk needing the shorter signal blocks around Secaucas transfer than the SWIFT connection. 

Anyway. just though it was cool to catch the new temporary cantilever signal 3E under test, several weeks before the first revenue train would actually use the new bridge.

*Note: Amtrak would ultimately open track 3 for service two days ahead of schedule due to a problem that fouled track #2 during the morning rush. 

 

Amtrak PORTAL Bridge Re-Labeling

The requirements of safety and signaling made railroads some of the first organizations to manage systems of unique identifiers and all their associated corner cases. Today we will explore how Amtrak is handling some of these corner cases as they replace the historic PORTAL swing bridge on the Pennsylvania Tunnel extension in the New Jersey Meadowlands.   

1910 vintage PORTAL swing bridge.

Let's first discuss names. Originally "W" cabin, PORTAL's current name emerged around the 1930's when increased use of voice-based telecommunications prompted the PRR to switch many of its interlocking identifiers from telegraph letter codes to names evocative of their local surroundings. At the time the swing bridge and its crossovers were the last interlocking station before the western portal of the North River Tunnels, thus PORTAL. In the mid-1990's Amtrak and New Jersey Transit implemented a connection between the DL&W main line and the Penn Station tunnel route immediately west of the PORTAL bridge. Branded Mid-Town Direct, this service would drastically decrease trip times compared to the 2-sear ride via Hoboken and someone came up with the name SWIFT for the new junction. 

"New" Eastbound PORTAL signal gantry over PRR era gantry.

 

Westbound gantry at SWIFT with route indicators.

The other important labeling system is for the universe of railroad tracks. It might seem straightforward to just start at 1 (or A) and advance upward, but on which side of the right of way does one start counting? What if you need to add a track on the "below" 1? I'll make a post about track numbering at some point, but in this case the PRR was forward looking and went with track #2 (eastbound) and #3 (westbound) since in 1910 it was foreseeable that traffic growth would require tracks #1 and #4 at some point in the future. When the Secaucus Transfer opened, the layout placed slower station tracks between main tracks #2 and #3. These were given letter designations with tracks A and B. PORTAL interlocking was even expanded to include switches into the western end of track A.  

1990's PORTAL extension to support new Track A with 80mph turnouts.

Fast forward to now and Amtrak is building a brand new PORTAL replacement bridge that will also replace most or all of the current PORTAL and SWIFT interlockings. However for the better part of a year both old and new bridges and tracks will be in service and keeping the names the same might result in safety critical confusion. As a result Amtrak proactively renamed the old tracks and interlockings in December, 2025 with PORTAL becoming OLD PORTAL, SWIFT becoming and OLD SWIFT, track #2 becoming track #22 and track #3 becoming #33.

It gets better because Amtrak employs a track number based labeling system for signals and interlocking appliances. This made signals like 2E and 3E into 22E and 33E. Likewise switches like #23 and #32 became #2233 and #3322. Note that lettered tracks are just assigned a number for the purposes of switch and signal labeling with 7 standing in for A, but because track A doesn't cross the bridge there was no need for it to participate in the renaming. 

The now renamed 2233 crossover and 227 turnout at SWIFT.

Like automatic signal number plates and interlocking station signs, track numbering is a fascinating topic that I will dive into at some point, but for now I'll leave things in the context of a topical news item. 

Policy Capture Ruins SEPTA's Suburban Trolleys

One reason often overlooked reason CBTC is problematic is that it provides management, lawyers and politicians the ability to reach forward and jam a broom handle in the spokes of the bike they are riding. Policy capture is the concept where an automation system allows "the powers that be" to implement policies that were previously impossible with a non-automated system. The most common example is on board announcements. While it would be difficult to go through the trouble of getting train operators to announce more than the next stop and "stand clear of the doors", an automated system can be programmed costlessly announce whatever management can think up, turning a generally quiet ride into a barrage of PSA's and nags. Well we have a new example of policy capture that stands ready to ruin SEPTA's Route 101 and 102 suburban trolleys. 

As previously discussed, the new CBTC signaling is replacing a stop-go block system that first used two lamp ABS signals and later regularly placed interlockings to ensure train separation. Since the Routes 101 and 102 utilize interurban type equipment that can run in street traffic, there was no need for a complex ABS system as the trolley operators could see a stop signal ahead and then stop at it like they would a vehicular traffic signal. In this case CBTC should have allowed for more frequent operation as on the dedicated rights of way the trolleys would be able to run much closer together. Instead the technology allowed for policy capture. 

While largely separated from road traffic, the Route 101 and 102 rights of way include many road crossings which are protected by crossbucks and traffic signals. Needless to say these are prone to the occasional trolley-motor vehicle accident. Attempts to install crossing gates to improve safety caused so much traffic congestion that the resulting public backlash not only halted the project, but saw the installed gates removed. This is the point where SEPTA could throw up its hands, say they tried and accept the occasional collision as a cost of car dependency, however this is where the CTBC system provided a hitherto impractical solution of enforcing a 10mph trolley speed at all road crossings. 

Deactivated crossing gates.

Sure, this could have been a operating rule, but such an awful policy would quickly be ignored by operators making SEPTA potentially liable for the negligence of road users.  However CBTC enforcing the speeds at every single road crossing took operators out of the equation and reduced the implementation cost to nothing. The only problem was that a 34 minute trip become a 49 minute trip. It's not clear how this will affect the ridership, but the cost of an half hour per day is likely to push more people onto the roads. 

CBTC beacon.

It's hard to argue against appeals to safety and thinking of the children. That's why sometimes the only way to win is to not deploy technology that makes enforcement possible. SEPTA's Route 104 used to be a suburban streetcar like the current routes 101 and 102, but was converted to bus operation in 1958. Today that bus can now travel far more quickly than a limited stop rail line on a dedicated right of way because, for the time being, those buses have human operators that are allowed to use their judgement and skill. A similar situation has also been reported on Toronto's Fitch West light rail line with the new LRV's taking up to 20 minutes longer than the previous buses due to an enforced 15kph speed restriction at intersections.