By the Numbers - Signal Number Plates

 I have previously discussed how railroads used milepost number places as an easy way to distinguish absolute from intermediate (ie permissive) signals.  Like pretty much every other facet of signaling I've covered these vary railroad to railroad and past to present so I figured I'd compile a guide to railroad number plates (which are distinct from Station Signs). 

Beginning with CSX, they use a white on black sign of medium side using a distinctive font that has been pretty consistent since the Chessie era.  The number is the milepost in tenths, ie without a decimal point.  If there is more than one main track is will be represented by a dash and the track number. Bi-directional signals use an odd-even system with one direction being the nearest odd 10th and the other being the nearest even 10th.  The choice of odd-even is not necessarily consistent across an entire line. 

CSX also has a compact style that has appeared at various points around the system such as the Trenton Line and former RF&P.

Speaking of Conrail, they used what is perhaps the best number plate system with a whole milepost followed by the track number followed by a directional letter.  If there was only a single track the track number 1 would always be used.

Trenton Line MP 30 Track 1 North

PRR Main Line MP 124 tk1 West.  Note Conrail letters re-skinned by NS.

This type of signal would only appear on re-signaled territory, legacy signals, especially in Rule 251 territory, would just be a milepost number sometimes prefixed by a branch letter or direction.

NS honors the former Conrail system on former Conrail territory, but replaces the unit number plates with a modular type, similar to what the original PRR used.

On NS's other territories a milepost in 10ths with no decimal is used with the odd-even system in effect.

Until around 2000, former Southern territory used a large black on white sign and before that bare reflectorized numbers mounted to the mast. Signals not only use the odd-even system, but where there are more than one track, the tracks will use sequential odd or even 10ths creating a spread of 4/10ths per signal location.

South Station Ersatz Position Dwarfs

It seems that our friend at L&W signaling have expanded their product range from just the long out of production PRR Position Light pedestal signals, recently seen on SEPTA, to the more common position light dwarf signal, still available from Safetran and other suppliers.

Although LED drop in lamps are available for position light dwarfs (see the 6S signal above displaying Slow Approach), Amtrak chose L&W's boxy replacements for the 7S and 8S stick dwarfs at the northern end of TOWER 1 interlocking at Boston South Station.

This may or may not be related to the others doings a-happening at South Station in the form of a new Luxury hotel that will cover up the open air space at the north end of the platforms between the Bus station and the current train hall.  About 2 car lengths have been cut from the platforms to make way for what I assume will be hotel space and with it the fixed PRR PL dwarf Stop indicator in front of the bumper blocks. Like the Tower 1 dwarfs, they have been replaced by an L&W product.

These seemingly out of place position light signals were installed in the late 1980's when the entire Tower 1 complex was re-signaled and I guess PL dwarfs were seen as distinctive for slow speed indications in otherwise color light territory, specially on gantry mounts.

NS Files to Abandon Signals on Numerous Lines

As the Class 1 railroad with the largest exposure to the failing coal industry, it is not surprising that NS has suffered the steepest traffic declines over the last year with carloads still down about 9% over 2019 figured, compared to under 5% for its peers. NS has surrendered to this reduced level of traffic by trying to cut its way into profitability, selling off huge portions of its fleer, closing facilities and now, the complete elimination of signal systems on a number of under performing lines.





Up first is the Albany District which where NS is requesting to have the ABS signaling system removed between Fort Valley and Albany, Georgia. The district is signaled under Rule 271 (ABS-TWC) using 70's vintage Southern style split ladder masts with Safetran heads.

BNSF to Retire Most ATSF ATS on 2/15/21

On Presidents Day 2021 (likely at Midnight between Sunday and Monday), in a move that was entirely foreseen and entirely understandable (unlike with the UP cab signals), BNSF will retire the Santa Fe era IIATS Automatic Train Stop system that was popular during the first wave of technical railway safety aids in the 1920's and 30's.

Bi-directional ATS shoes under a classic ATSF signal bridge on the Marceline Sub.

 The inductive system, similar to the magnetic Automatic Warning System in UK service, was identifiable by the upside-down canoe shaped shoes mounted to the right of the track.  When activated by a signal displaying an indication other than Clear, the shoes would trigger a warning horn in the cab and failure to acknowledge would result in a penalty brake application.  Set as the most basic requirement by ICC directive for travel 80mph and over after 1948, railroads couldn't abide by its modest cost, resulting in an unofficial nation-wide rail speed limit.  While the Southern, New York Central and Santa Fe maintained hundreds of ATS equipped route miles, all but the ATSF managed to abandon their systems around 1970 with the general collapse of passenger services.  For whatever reason, the ATSF Chicago to LA "Super Chief" route retained its ATS system, allowing the successor Amtrak Southwest Chief to travel for long distances at speeds up to 90mph. 

Inert "always on" ATS shoes protecting a permanent speed restriction on the Marceline Sub

A clever system that could fail safe with just inert steel components, IIATS was in service on the Marceline Sub across Missouri and the Needles, Seligman and Gallup Subs between Barstow and Dalies, allowing for speeds of up to 90mph on Class 5 track.  Unfortunately the system relied on careful clearances between the lineside shoes and the pickup coils, that were mounted, as needed, only on the head end locomotives on freights traveling this territory. Moreover, BNSF went out of its way never to expand the system from what they had inherited, therefore as tracks were upgraded to bi-directional operation, the ATS would remain in the old single direction ABS configuration. In other cases ATS was only in service in one direction on both tracks.  

ATS shoes for westward movements only on both tracks on the Seligman Sub.

The good news is that active PTC is being accepted by the FRA as a valid ATS replacement.  Moreover, in the affected areas since signaling, track and grade crossings are all configured for 90mph, speeds will either remain at 90mph or will be raised to 90mph where ATS did not cover specific directions of travel.  It remains unclear if previously non-ATS territory that is equipped with Class 5 (90mph pass, 70mph freight) track, will see similar speed increases. I have been informed that, similar to the METRA ATS shoes, the timetable for removal is 90-180 days.  However the BNSF ATS territory is probably 10+ times the total route territory, so we'll see.

Railrunner territory semaphore with ATS shoe on the Glorieta Sub.

Due to absent or incomplete PTC, ATS will remain on parts of the Glorieta (controlled by New Mexio Railrunner), Raton, LaJunta and Topeka Subs, however it has been all or partly suspended on most of this territory since the early 2000's, lowering speeds to 80mph where applicable. Due to the nature of how ATS works, I have been told that Amtrak Train 3 and 4 run with the system on, but do not report any activation issues.

ATS shoe on the NJT RiverLINE.  The only instance where IIATS is used as a trip stop.

In addition to the Chief route, ATS will remain in service, enabling 90mph on the former ATSF San Diego route, now playing host to Amtrak Surfliner Trains as well as on the NJT RiverLINE where the technology is used, shockingly, to enforce positive stops at absolute signals.  Anyway, get your photos (or after 2/15 get your ATS shoes) quickly because after President's Day, they could start to vanish without warning.