Enjoy these clips I took while operating the oil train and Essex helpers! At the summit of Marias Pass, an oil train has just switched directions at the upper reverse loop, and it's about ready to head down the grade in the westbound direction. While I only model the western slope of the pass, it's still implied that this train had to climb the eastern grade. However, with no rear DPUs, this 15,400-ton WB crude oil train not only needs the extra horsepower to make it up the grade, but it also needs the added dynamic braking effort heading down the 1.86% western slope. At right around 143 tons per operative brake (TOB), the BNSF timetable for this line dictates that a minimum of 4 locomotives (32 rated dynamic brake axles) are required. On my layout, I try to simulate these rules and the occasional usage of WB helpers by sending the Essex helper set up to Marias summit.
In this video, the Essex helpers first couple to the rear of the WB oil train before BNSF 4313 begins its journey west. The helpers pull back on the drawbar to keep the coupler slack out, and the whole consist passes Essex before descending into Columbia Falls where they eventually stop. At Columbia Falls, the helpers uncouple and head back up to their helper base at Essex, MT. They will wait until an EB train (or perhaps another WB!) requires their assistance.
0:00 Helpers couple to oil train
0:15 BNSF 4313 heads west
1:58 Blacktail siding
3:39 Belton (West Glacier), MT
4:20 Arriving Columbia Falls, MT
6:31 Helpers return to Essex, MT
8:55 Getting parked away on the yard lead