On April 26th, 1956, the Ideal-X left the Port of Newark, New Jersey, to the Port Houston, Texas, which was called 5 days later. It carried 58 35-feet (8 feet wide by 8 feet high) containers, along with a regular load of 15,000 tons of bulk petroleum. The 35 feet unit represented at that time the standard truck size in the United States. This first containership was converted under the initiative of Malcolm McLean (1914-2001), a trucking magnate who saw the tremendous potential of containerization, particularly in terms of loading and unloading costs. McLean calculated that in 1956 loading a medium-sized ship the conventional way was costing $5.83 a ton. Comparatively, loading the Ideal-X would cost less than $0.16 a ton. The economic advantages of such a mode of transportation thus became clear to the shipping industry.
The initial goal of McLean was to create an integrated transport system in the United States where coastal shipping would complement road and rail transportation. This goal was difficult to achieve because of the segmented nature of the industry. Further, the development of the Interstate Highway System in the United States during the 1960s improved the efficiency of trucking considerably.
In 1960, McLean founded SeaLand, a major container shipping line, which was purchased in 1999 by Maersk, the world’s largest container shipping company. The Ideal X carried containers until 1965 when it was scrapped.