Ten hoppers coupled to the Big Boy consist in January 2014 were used for additional braking power.
Steve Sweeney
Q Why was there a string of hopper cars in the consist moving Union Pacific Big Boy No. 4014 from Pomona to West Colton, Calif., in January 2014? – David Tritenbach, Kerrville, Texas
A Although Union Pacific’s Big Boy No. 4014 is equipped with what the UP Steam Crew calls a “parking brake,” consisting of an air compressor tied into the locomotive’s original brake cylinders, the Big Boy needs more stopping power for moves until it is restored, hence the hoppers.
The purpose of the 10 hoppers in the Big Boy’s consist was to add the stopping power of their brakeshoes to help slow the Big Boy when air brakes were applied. Each of the locomotives and hoppers in the consist had a margin of extra braking force available to take up the Big Boy’s roughly 450 tons of dead weight while in motion. A similar consist made up of flat cars was used for the longer journey to Cheyenne, Wyo., later in the year. – Steve Sweeney
