Caption: Nearly new CP Rail SD40-2 units 5606 and 5621, the rain accentuating their fresh red paint, grind upgrade between the two Spiral Tunnels at Yoho leading a freight. Trailing CP GP9 8680 and leased Precision National (PNC) GP7 127 are also working hard, evident by their visible exhaust. Reg appears to have stopped on the Trans-Canada Highway between the two tunnels to get this shot from the bridge.

At the time, CP was starting to get its first groups of the brand new 3000hp 6-axle GMD SD40-2 model. 5606 was outshipped from GMD's London, Ontario plant on May 31st 1972, and 5621 outshopped June 29th 1972 (making it only a few weeks old). The "Dash 2" model was an improvement over the earlier SD40 design, and a lot of the older 4-axle power still running around would soon be shown the door: the GP7 and GP9 fleets would remain, but the leased PNC power, Fairbanks Morse/CLC units, and most of the Alco/MLW 539- and 244-powered fleet would be phased out in the following years in favour of hundreds of new SD40-2 units that would dominate CP's mainlines through the Rocky Mountains until the arrival of new GE AC4400CW units in the mid-late 90's.

Reg Button photo, Dan Dell'Unto collection slide.