UP Wimmer Engineering Special

Every now and then, Union Pacific runs inspection specials – nothing unusual. However, yesterday I got word that the latest of these trains – the Wimmer Engineering Special (hereafter referred to as the Special or just W.E.S., as the full name is just too darn long)- would be running over the Moffat from Helper, UT, to Denver, CO, and then over the Joint Line to Pueblo, CO, on Wednesday, Aug 13, 2003. Better yet, the power for the train was UP 6936 – the only remaining operational DD40AX “Centennial” unit. Since I kind of had the afternoon off of work anyway, I decided it might be fun to catch.

Originally expected in Denver by 1400h, it didn’t even come close to making its schedule. According to the dispatcher, it didn’t even enter the tunnel until around 1500h, and even then I didn’t see it until 1605h at milepost 23. For those unfamiliar with the area, MP23 is just above the Colorado 72 bridge, and just down from Tunnel 1 on the Moffat. Fortunately, I had a couple of trains to keep me from boredom in the meantime, but once I’d gotten 6936 at MP23, it was off for Leyden. With the late afternoon traffic in Denver, I only beat it to Leyden by a minute or two at most, and then turned around and headed for C-470 to beat it down to the Joint Line.

Once on the Joint Line (delayed slightly by a traffic jam), a slow southbound coal drag, lead by BNSF 5600, clarified that the Special hadn’t yet gotten ahead of me. There was no way that coal train could have made it as far as it had and still let the Special out in front – the special had to be behind it. Sure enough, while watching the southbound load, 6936 called in as just having passed Littleton. This coal train was to be a blessing and a curse for the rest of the day. On one hand, it made chasing the Special extremely easy because it slowed it down to a ridiculously slow speed. This allowed for shots near Louviers, then again at Sedalia (which didn’t turn out), and again three different times around Castle Rock. On the other hand, it eventually stalled, preventing the Special from making it much past Castle Rock, CO, in the daylight. Eventually, long after sundown, 6936 was even required as a helper to push BNSF 5600 and a loaded coal drag over Palmer Divide, though I didn’t personally see it.

There’s not much more to say – just a fun day out in beautiful weather chasing a rather unusual locomotive and train. Enjoy!


All shots in this trip report were taken with a Canon EOS 10D with a Canon 28-105mm USM or a Canon 75-300mm f4-5.3 IS/USM.

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