In 1952, the cabin layout on northern trans-Atlantic routes was changed to one with a first and a tourist class. First class had comfortable chairs in which one could sleep, given the name "Slumberettes". Those sleeping chairs were soon succeeded by beds, modelled after the U.S. Pullman railway cars. Two adjacent seats were moved toward each other and formed a lower berth. The wall panel could be folded downward, forming the upper berth in which the other person could sleep. A year later, tourist class was introduced on Europe flights.