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  • Loco tonnage ratings

  • Discussion relating to the past and present operations of CPR. Official web site can be found here: CPR.CA. Includes Kansas City Southern.
Discussion relating to the past and present operations of CPR. Official web site can be found here: CPR.CA. Includes Kansas City Southern.

Moderators: Komachi, Ken V

 #1473288  by KevinD
 
Does anyone with older 1980s era timetables or rule books have the max tonnage figures that CP SD40-2s were allowed on the Mountain Sub (between Golden and Revelstoke) during the era before the newer McDonald tunnel was built? Looking for the per-unit tonnage allowance that SD40-2s were permitted up the grade to the old tunnel. The newer timetables available at Multimodalways has the track diagram and gradient data, but does not list the tonnage limit per various loco model. It's as if the power assignment bureau handles that now and that data does not need to be in the hands of the employees out in the field.

Various youtube videos show the heavy grain trains arriving at Rogers helper base with 4 SD40s up front, 2 more midtrain coupled to a remote car, and the 6-unit Rogers manned helper cut in towards the rear and charging up that 2.4% with 12 SD40s 36,000 hp total.
 #1476495  by Engineer Spike
 
I don’t know the ratings for that line. There were two different SD40-2 ratings, however. Some had enhanced traction control, while others did not. I’m sure most of the western assigned power had it. As the AC power came, new power was assigned out west. As new units arrived, older ones were pushed east. Here we started to get the enhanced SDs, and eventually the oldest AC4400s. Now it seems like the AC fleet pretty much free floats. The new 87, 88, 89, and 9300 classes might be just as likely to be on the D&H, as it is to be in Calgary.
 #1483961  by Engineer Spike
 
I missed the point of the post about tonnage ratings in the timetable. They have a computerized train makeup program, which figures the locomotive power, tonnage, types of cars, etc. The section of the General Operating Instructions dealing with this had the flat tonnage rating. The timetable listed the multiplier for the line’s gradient, which could increase or decrease the rating, depending on if you were headed uphill or down.