The first oceangoing steamer designed and built to carry oil in bulk was the Belgian-flagged Vaderland, which was built in 1872. The intended service of this vessel was to carry immigrants to the U.S. and return to Europe carrying petroleum. Prior to the first voyage, however, the authorities forbade the scheme as being too dangerous. The ship was then converted to a passenger cargo liner and never carried an oil cargo.
The first prototype of the modern tanker was the Gluckauf of 1886. There were, however, numerous sailing ships owned by oil companies at the time. Interestingly, one such sailing tanker remains, the Falls of Clyde, currently laid up in Honolulu.
Until recently, most tankers were fitted with a dry cargo hold, usually located near the forecastle, and included cargo booms for the loading and discharge of cargo. The hold averaged 15,000 cubic feet and was used for the carriage of barrels, cases and drums of lube oil or oil and chemical products.
Tankers have been known to enter the dry trades. In 1944, World War II was raging across the European continent. The agricultural regions were devastated and what little grain remained in the fields could not be harvested with the farmers serving as soldiers. Europe’s cities faced starvation. The Battle of the Atlantic had fully employed all the dry cargo ships.
Due to the urgency in Europe, a bold experiment was undertaken — bulk grain would be loaded into newly built tankers that had never been in the oil trades. It was decided that these vessels were to load at Canadian ports. The experiment became a success. These vessels did get safely across, although not much is known about their voyages.
Tankers did not enter the grain trade again until 1954, when economics dictated their return. The first vessel in this trade was the 1926-built Gulfcrest, owned by the Gulf Oil Co. This vessel initially had been employed for 27 years in the carriage of crude oil around the Caribbean and U.S. East Coast.
It should be noted that in 1954, the Grain Rules from the 1948 International Convention for the Safety of Life at Sea (SOLAS) were in effect and these rules called for the installation of bins and feeders in all spaces where bulk grain was to be loaded. However, the traditional tanker had holds or tanks that were subdivided by longitudinal and transverse bulkheads that honeycombed the hull into about 30 compartments or individual tanks. Thus, it was rather impractical to attempt to fit these ships with bins and feeders.
On the other hand, tankships have inherent stability advantages. To accommodate the free surfaces of liquid cargoes, the longitudinal bulkheads were located to greatly reduce the transverse heeling moments. This design, therefore, similarly accommodated the potential shift of the grain, a commodity that, although it could move after stowage, was less fluid than liquid.
Thus, the first grain rules for tankers were issued in 1954 that set forth regulations on the required ship structure, fittings and cleanliness.
It should be noted that not all vessels intended to carry oil met the criteria. Structurally, this required the vessel to be subdivided by two or more suitably placed longitudinal bulkheads and not be fitted with double bottoms.
Over the years, hundreds of tankers were employed in the grain trades. Today, however, there are fewer tankers being built that can meet the criteria of the grain rules and thus fewer tankers are employed in the grain trade.
During World War II there was a great demand for sea transport, and the idea of using the open deck space of a tanker for the transportation of airplanes was developed. The wartime installations were nicknamed “Meccano decks” because they resembled Meccano toys, similar to Erector Sets. The ships, for the most part, were standard T-2 vessels that easily lent themselves to the composition of uniform steel or aluminum beams that when bolted together could be adopted to most standard tanker decks.
After the war, when these tankers were turned over to private operators for civilian use, the Meccano decks were removed to eliminate topside weight, which was of no use to a private operator.