Former Dallas Terminal Railroad Re-signaling

 The Dallas Terminal Railroad can be considered to be in the midst of a slow-motion re-signaling, partly set off by Amtrak move from Union Pacific to TRE routing between Dallas and Fort Worth. This matters because the stretch of of 5 back-to-back interlockings, while "modern" in appearance, actually represents a vestige of late stage relay interlocking installed in the 80's or 90's with quirky signals of a non-Safetran nature.

The stretch in question used to be covered by the Dallas Terminal Railroad's Towers 106 and 107 that managed the west and east ends of Dallas Union Station. This has since become part of the Union Pacific Dallas Sub and from east to west consists of REUNION, DALLAS, JFK JCT, TRE JCT and INDUSTRIAL X-OVER interlockings. An additional interlocking, BN CONNECTION, makes up the third corner of the wye with TRE JCT and JFK JCT.

Around 2015 Amtrak shifted from the UP Dallas Sub to the ex-Rock Island Trinity Rail Express commuter route west of Union Station. Around 2023 the switch that connected the Amtrak platform at Union Station to the Dallas Sub was removed along with the west leg of the wye, turning both TRE JCT, BN CONNECTION and the TRE portion of JFK JCT into vestigial interlockings with signals guarding empty track. REUNION also saw the removal of the crossover to the east end of the Dallas MoW/passenger car storage track.

In 2026 the other shoe dropped with the vestigial JFK JCT signals being removed and new signals going up at DALLAS. I don't know the exact plans, but there are two clear options. The first is that DALLAS loses its crossover and becomes an interlocked connection to the MoW stub with other interlockings staying unchanged. The second, and what I consider to be the more likely scenario, is that JFK JCT will be merged into DALLAS with INDUSTRIAL XOVER and the vestigial TRE JCT being eliminated along with BN CONNECTION. Currently trains on track #1 encounter 4 signals within 3000 feet, not a situation that is likely to play nice with PTC. Moreover, INDUSTRIAL XOVER duplicates the facing point crossover available at DALLAS. While its possible INDUSTRIAL XOVER might be kept something tells me that it is surplus to requirements.

So why does this all matter? Like I said the current setup uses late stage all or partial relay logic and non-Safetran signals consisting of L&W modular and GRS monobloc equipment. Second the close signal spacing introduced some very interesting signal progressions. In fact because of the sharp turn of the Dallas Sub at JFK JCT, the default progression for track #1 westbound is an Approach Restricting at DALLAS to a Diverging Clear (straight clear is onto the TRE) at JFK JCT. I suspect the new interlocking will display a Clear to UP train movements despite the curve. All together, what is an accessible place to observe interesting signal indications on interesting signals is about to get much less interesting, even if the exact amount of uninterestingness remains to be seen.