Mazda Cab Signals are the PTC Solution We Needed

While driving in a brand new rental Mazda sport wagon in Colorado I noticed something interesting on the instrument cluster.

There was a dynamic speed limit indication accompanied by a red tick on the speedometer indicating the currently detected speed limit. Now this sort of information has been available in Waze for some time, accurately using smart phone grade GPS to pull a road segments speed limit from a crowd sourced database and displaying it on the interface. Using something like Android Auto this could be displayed to he driver in any number of ways.

The cybersecurity implications of this aside, I noticed an interesting Mazda party trick that Waze could not perform and that was the seeming ability to detect temporary speed restrictions, aka work zone speed limits. Waze explicitly rejects trying to track TSR's, even for long term work zones. Although achievable through traditional data collection methods, I was aware that the vehicle was equipped with forward facing cameras for its lane-assist feature (or MCAS) and if on-board systems could keep track of lanes, they could also recognize wayside speed limit signs and display them on cab signal, possibly augmented by a Waze style database.

The current national Class 1 PTC standard, ETMS, relies on wireless data and GPS to track a trains position and compare is, Waze style, to a database of authorized speed limits. The problem this creates are clunky data networks that result in slow setup time and en-route loss of connectivity as well as occasional mass outages that can halt traffic across a railroad's entire network. The preferable solution has been evident in the field of vehicle automation for over a decade now. Computer vision systems just look at wayside signs (and/or signals) the same way the human engineer does. To the extent that wayside signs are vulnerable to impairment computer vision doesn't have to replace the current "Waze" type system, but in case ETMS suffers a failure, the backup solution isn't halt all traffic (or god forbid just let the crews do their job), but fall back to wayside sinage detected by computer vision and enforced by the on board apparatus 

NS D&H Re-Signaling Hits Afton, NY

In yet more fallout from the NS purchase of the former D&H Main Line, the re-signaling ax has hit the siding in Afton, NY after randomly bouncing around the line between Schenectady and Sunbury, PA. The real shame was that at least the north end of the siding, CPF-587, was on track to stay searchlit under CP ownership.

As of 2014 CPF-587 had two CP type GRA SA searchlight masts on the south end that replaced a D&H style searchlight bracket at some point between then and 2008.

CPF-587 also had a D&H vintage single track cantilever mast at the north end that remained untouched until the summer of 2022(!) when a Canadian Pacific in-house type searchlight mast went up.

It is unclear if this was part of a long term Canadian Pacific plan that NS management later nixed or just something NS scraped together as a temporary measure, but by fall 2023 both the out of service bracket and active cantilevers were gone with Darth Vaders and a new relay hut in place.

Although this was always to be expected and CP was in the midst of its own scattershot re-signaling of the D&H line. It is a major shame to lose one of the best preserved interlockings on the route in so short a space of time. Unfortunately the D&H route is well off the beaten path and I my best efforts have only allowed me to nibble at the ends. If you live in the I-88 corridor please do your best to get some photos at those interlockings that remain.

 

 

 

The Ultimate Cutover - SEPTA 90TH ST JCT SOUTH

Typically when one discusses a signal cutover one is cutting new signal logic over to control new or existing signals or interlocking appliances. Sometimes one will cut new signals or interlocking appliances into existing signal logic. However in 2014 when SEPTA wanted to relocate 90TH ST JCT SOUTH interlocking 2000 feet to the north to expand a Conrail SAO industrial siding they took things a step further and relocated the entire signaling bungalow.

Above is a street view of the original location in 2014. Below is the new location in 2015. SEPTA didn't even bother to clean the graffiti off the relay hut.

Part of the penny pinching shown here is due to 90TH ST JCT SOUTH being solely the domain of Conrail freight movements before they hit the SEPTA Airport Line at 90TH ST JCT NORTH. Without a Federal or State grant to pay for the capital improvement, there was no incentive to pad things out and create more jobs and with traffic being pretty minimal there wasn't a cost incentive to minimize down time due to testing. This just goes to show when the costs align, railroads will save money on signaling.

Southern Pacific Cantilever Zapped by Caltrain Electrification

In a completely predicable turn of events, the iconic Southern Pacific cantilever mast that has guarded the southern approach to the 4th and Kin St terminal in San Francisco has met its demise sometime between March and October of 2023, likely in conjunction with the erection of overhead electrification wires. It has been replaced by three LED searchlight dwarfs.

I've noticed that starting with Amtrak's New Haven to Boston electrification. recent North American electrification projects have included far more overhead clutter than those seen in Europe. Specifically the use of solid overhead beams to mount the wire brackets as opposed to cable spans. Cable spans don't tend to block signal sight lines as much, allowing existing signal placements to remain.

Anyway, I'm not sure if the 4TH ST cantilever was scrapped or donated to a museum, but as one of the last of its type in daily service, its loss is significant.