Stern sculling
Stern sculling is the use of a single oar over the stern of a boat to propel it with side-to-side motions that create forward lift in the water. The strict terminology of propulsion by oar is complex and contradictory, and varies by context. Stern sculling may also simply be referred to as "sculling", most commonly so in a maritime situation. In fresh water, and particularly in sport rowing, sculling is use of two oars on either side of the boat by each person, in contrast to sweep rowing, whereby each boat crew member employs a single oar, complemented by another crew member working on the opposite side with their oar.
Overview
Stern sculling is the process of propelling a watercraft by moving a single, stern-mounted oar from side to side while changing the angle of the blade so as to generate forward thrust on both strokes. The technique is very old and its origin uncertain, though it is thought to have developed independently in different locations and times. It is known to have been used in ancient China, and on the Great Lakes of North America by pre-Columbian Americans.In stern sculling, the oar pivots on the boat's stern, and the inboard end is pushed to one side with the blade turned so that it generates forward thrust; it is then twisted so that when pulled back on the return stroke, the blade also produces forward thrust. Backward thrust can also be generated by twisting the oar in the other direction and rowing. Steering, as in moving coxless sculling shells in crew, is accomplished by directing the thrust. The oar normally pivots in a simple notch cut into—or rowlock mounted on— the stern of the boat, and the sculler must angle the blade, by twisting the inboard end of the oar, to generate the thrust that not only pushes the boat forward but also holds the oar in its pivot. Specifically, the operation of the single sculling is unique as turning the blade of the oar in figure 8 motions operates them. It is not hoisted in and out of the water like any other traditional oars. The objective is to minimize the movement of the operator's hands, and the side-to-side movement of the boat, so the boat moves through the water slowly and steadily. This minimal rotation keeps the water moving over the top of the blade and results in forces that transfer to the multi directional row-lock, or pivoting mount, on the side of the hull thus pushing the boat forward. Steering the boat is a matter of rotating the oar to produce more thrust on a push or pull of the oar, depending upon which way the operator wants to go.