For station keeping and maneuvering, the Canadian St. Laurent class frigates used 40 yards/knot for acceleration and deceleration. For example, if approaching a 12 knot tanker to conduct a replenishment at a stationing speed of 20 knots, the engine order to go to 12 knots would be given at (20 - 12 knots) x 40 yards/knot = 320 yards. By the time the frigate was at 12 knots it was in station alongside the tanker.