In November 1944, a group led by Benjamin W. Franklin, took over the management of the Cartierville plant in Montreal from Canadian Vickers, their former employers. Franklin's new company, Canadair Limited, had contracted with the Canadian government to assume the aircraft design and manufacturing activities previously undertaken by Canadian Vickers. Before becoming part of Bombardier Inc. in 1986, Canadair produced over 4000 aircraft, including the North Star. See the Canadair history Web site for more information about the history of one of Canada's best known aviation companies.

The same year that Canadair took over the Cartierville plant, 1944, the Canadian government obtained a license to build an aeroplane using components of the Douglas DC-4 and DC-6 aircraft. Much of the engineering design work was carried out at the Trans-Canada Air Lines (TCA) facilities at Winnipeg and Montreal (Dorval), and at Canadair's Cartierville plant.

The new airliner, officially designated DC-4M in its pressurized civilian configuration, and C-54GM in its unpressurized RCAF version, was christened North Star by Ben Franklin after considering other names including Polaris. Although it looked very much like the Douglas DC-4 and DC-6, the North Star's four Merlin engines made it easily distinguishable from its American cousins.

Throughout 1945 Canadair prepared for the North Star's production and in 1946 the first aeroplane, a C-54GM with civilian registration CF-TEN-X, was completed. On the 15th of July, 1946, CF-TEN-X took it's first flight at Cartierville — a short twenty-five minutes in the hands of Canadair test pilot Al Lilly. Larry Milberry includes an account of that first flight in The Canadair North Star [Milberry] by Clayton Glenn, who was on the first flight because he was an expert on the North Star's propeller control unit. Glenn says that just after takeoff the landing gear was raised and the "cockpit filled with smoke and the smell of burning rubber". Bob Brush, a Douglas test pilot, was also in the cockpit and explained that the smoke and smell came from the "nose wheel spinning against the up brake".