Covered Hopper, 4-Bay, Cylindrical HS 4550

History: In the 1970's, Canadian National & Canadian Pacific developed a concept for a standard 4550 cubic-foot 4-bay cylindrical hopper. The basic design of this hopper was developed into two car types, one for grain and similar consistency products and another for potash, dry chemicals and fertilizers.

The most obvious difference between these two types of cars can be seen in the loading hatches on the top of the cars. The grain version of the car has trough hatches spanning the length of the body top, while the potash version has a series of round hatches spaced along the length of the body.

During the production life of the design, thousands of these care were manufactured in various production runs by three different manufacturers. Hawker Siddeley produced many of these cars over the production run, and in total produced 15 variations of the basic design between the grain and potash types of this car.

Today, thousands of these cars remain in service with Canadian Pacific, Canadian National and a number of other operators. Many can be seen in their original "Heritage" paint schemes, as well as more modern schemes, such as the colorful 2008 Green Saskatchewan Grain Car Corporation scheme. Though they initially were primarily seen in Canada, they now travel the rails of North American from Canada to Mexico, with operations in many parts of the United States.

Railroad/Company: Hawker Siddeley Canada was the Canadian unit of the Hawker Siddeley Group of the United Kingdom and manufactured railcars, subway cars, streetcars, aircraft engines and ships from the 1960s to 1980s.

Founded in 1962 as the Canadian division of British Hawker Siddeley Group, the company assumed the assets of the A.V. Roe Canada Company Ltd. Hawker Siddeley Canada focused on manufacturing heavy rail cars (hopper and tank cars) and transit vehicles (subway cars, intercity railcars and streetcars). Hawker Siddeley Canada headquarters was in Mississauga, Ontario. Its formation in 1962 saw the company acquire control of several A.V. Roe Canada subsidiaries including the Canadian Car and Foundry (CC&F) as well as the Dominion Steel and Coal Corporation (DOSCO) conglomerate, which included various steel mills, coal mines, manufacturing plants, and Halifax Shipyards.

Hawker Siddeley Canada's operations were then acquired by Kingston-based UTDC (later sold to Bombardier Transportation of Montreal, Quebec). SNC-Lavalin purchased the railcar business but mothballed the TrentonWorks plant, which was later acquired by the Government of Nova Scotia and sold to Greenbrier. SNC-Lavalin sold the Thunder Bay plant to Bombardier Transportation and the Hawker Siddeley Canada name was ultimately dissolved in 2001.