A whaleback was a type of cargo steamship of unusual design, with a hull that continuously curved above the waterline from vertical to horizontal. When fully loaded, only the rounded portion of the hull (the "whaleback" proper) could be seen above the waterline. With sides curved in towards the ends, it had a Spoon-shaped bow and a very convex upper deck. It was formerly used on the Great Lakes of Canada and the United States, notably for carrying grain or ore. The sole surviving ship of the "whaleback" design is the , which is docked in Superior, Wisconsin, as a museum ship.
The term developed in common usage in response to the ship's appearance when fully loaded. A total of 44 such vessels were constructed from 1887 to 1898. All but two were built initially as for service on the Great Lakes. Six were built at Duluth, Minnesota; 33 were built at West Superior, Wisconsin; 2 at Brooklyn, New York; one at Everett, Washington; and one at Sunderland, England. A number of the Great Lakes vessels left the lakes for service on saltwater seas.
The term "whaleback" has also been applied to a type of high speed launch first designed for the Royal Air Force during World War II, and to certain smaller rescue and research vessels especially in Europe that, like the Great Lakes vessels, have hulls that curve over to meet the deck. An example of the former is the British Power Boat Company Type Two 63 ft HSL. The designation in this case comes not from the curve along the gunwale, but from the fore and aft arch in the deck.
Another application of the term is to a sheltered portion of the forward deck on certain British fishing boats. It is designed, in part, so that water taken over the bow is more easily shed over the sides. The feature has been incorporated into some pleasure craft based on the hull design of older whaling boats, in which it becomes a "whaleback deck".
McDougall had learned from experience the difficulties encountered in towing these vessels. The bows and spars made them subject to the forces of wind, wave, and the prop wash from the towing vessel, with the result that they often did not follow well. His purpose was specifically to create a barge design that could be towed easily and would track well.
When fully loaded, only the curved portion of the hull remained above the water, giving the vessel its "whaleback" appearance. Waves, instead of crashing into the sides of the hull, would simply wash over the deck while meeting only minor resistance from the rounded turrets. When fitted with hawse pipes for anchors and a guide for the tow cable, the bow somewhat resembled the snout of a pig, from which came the alternate and usually derisive appellation of "pig boat". Jokes and scoffers aside, the design performed as McDougall expected. Whether towed or under their own power, they were seaworthy vessels and fast for their time, averaging .
The remains of the Thomas Wilson lie just outside the harbor of Duluth, Minnesota. Thomas Wilson was wrecked as a result of a collision with the vessel George Hadley, which was inbound for the Duluth harbor at the same time Thomas Wilson was departing Duluth. The wreck is listed on the National Register of Historic Places. A well-preserved wreck in 70 feet of water at the east end of Lake Superior was confirmed in 2022 to be that of whaleback barge 129, exactly 120 years after its loss.Nelson, Tim, "Whaleback barge lost for 120 years discovered in depths of Lake Superior", MPR News, October 13, 2022.
Whalebacks were vulnerable in collisions. Their low profile made them hard to see, and also led at times to the other ship riding up over the whaleback in a collision, such as the collision between Thomas Wilson and George Hadley. While metacentrically stable as originally built, their design has been accused of not responding well to major refits that may have made some of them top-heavy. For example, SS Clifton was built as a conventional whaleback in 1892 and was refitted as a self-unloader in the winter of 1923–1924. The converted whaleback did not complete even one year of service; it foundered in a Lake Huron storm in September 1924.
Rather than a prototype of the standard bow-helmed lake freighter to follow, most whalebacks were "stern enders", a unique variation on the design that started with R. J. Hackett in 1869 and advanced with SS Onoko (regarded as possibly the first iron-hulled Great Lakes-style bulk carrier) in 1882. These "lakers" consolidated above-deck cabins at the extreme forward and aft limits of the hull to leave a large open area above the hold for both loading and unloading equipment, and had hulls with nearly box-like cross sections to allow maximum cargoes in shallow water.
Significant vessels
Drawbacks
Historical perspective
See also
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