Operating speed profiles and the ship design cycle

One key, but little documented and empirically supported, input in the ship design cycle is the expected operating speed profile. This real-world constraint affects many decisions regarding bull form and power systems, from fuel tanks to main propulsion and ship's service machinery selection and operation. These decisions, in turn, ripple through the design of a ship in ways that are often bard to discern, but clearly impact acquisition and life cycle costs. Recent studies of DDG 51 operating speed profiles demonstrate that the Navy regularly operates with speed profiles considerably different than used to design the ship. In general, warships operate in standard engine order telegraph increments (e.g., Ahead 2/3) and at lower speeds than designed for.