Twin-skeg stern

A twin-skeg stern carries two slender longitudinal skegs in the afterbody, each housing one propeller shaft, so the ship has twin screws fed by a cleaner, more uniform wake than a single-screw stern gives. Splitting the afterbody into two demihull-like skegs lets each propeller work in its own well-conditioned inflow, which cuts wake non-uniformity, propeller-induced pressure pulses, and vibration, and allows larger-diameter, slower-turning, more efficient propellers on a shallow-draft full hull. It is common on full-form ships, large LNG carriers, and shallow-draft river-sea vessels where a single propeller would be too large or too loaded. The cost is added wetted surface and structural complexity in the twin skegs and their bossings compared with a single skeg.