Four-funnel liner

A four-funnel liner, also known as a four-stacker, is an ocean liner with four funnels.

At the turn of the 20th century, as national shipping companies competed for passengers on the lucrative transatlantic route between Europe and America, a series of increasingly large, luxurious and fast ocean liners were built requiring four funnels to service their expansive boiler rooms. As they were introduced onto the North Atlantic many of the four-stackers would claim prestigious accolades such as the largest, longest or fastest ship in the world. An ocean liner with four funnels rapidly became symbolic of power, prestige and safety to the travelling public and shipping companies leveraged this trend extensively to market their best ships. The narrative that four-stackers were emblematic of safety was shattered with the loss of the RMS Titanic, sunk on her maiden voyage in 1912. While the naval architecture of four-funnel liners started to give way to more efficient ship layouts in the 1910s the distinctive profile of the four-funnel ocean liner has firmly endured in the public consciousness well into the modern age, largely due to ongoing interest in the loss of the Titanic as well as the sinking of the RMS Lusitania, which significantly altered the course of World War One.

SS Great Eastern was the first four-funnel ocean liner briefly operating in this configuration in 1867. SS Kaiser Wilhelm der Grosse, launched in 1897, was the first ocean liner purpose built with four funnels and was the first of the golden era of ocean liners that became prominent in the 20th century. In all, 15 four-funnel liners were produced; Great Eastern in 1858, and the remainder between 1897 and 1922. Titanic sank on her maiden voyage, four more were sunk during the World Wars, and the other ten were all scrapped. The last four-funnelled liner ever built was RMS Windsor Castle; however, two of her funnels were later removed making the RMS Aquitania the last four-funnel liner in service and the only one to survive service during both World Wars.