The Canadian Pacific was the only North American railroad to operate the 4-4-4 type on more than an experimental basis. In the later 1930s he railroad introduced two classes of 4-4-4, which it styled the "Jubilee" type in honor of the fiftieth anniversary of its transcontinental passenger service. Curiously, the F1a class was the second to be built, appearing in 1936-37. Eventually assigned to local passenger service, the F1s had 75-inch drivers and 16½x28-inch cylinders and a boiler pressure of 300 pounds per square inch. With these dimensions they exerted about 25,900 pounds of tractive force. Weighing 218,000 pounds, they had a grate area of 45 square feet, an evaporative heating surface of 2291 square feet, and 900 square feet of superheater surface. They were semi-streamlined in the fashion of the earlier F2s and the CPR's Royal Hudsons, delivered in 1937.

Above, No. 2926 of class F-1-a poses in Windsor, Ontario in a photo of unknown origin, courtesy of Tom Rock of T.D.R. Productions. Two examples of the F1a "Jubilees" survive including the last member of the class, No. 2929, currently in sad-looking condition at Steamtown National Historic Site.