Anyone know the rules of the road in that sea with heavy ship traffic-- I sail small sailboats close to shore. Maybe someone with naval background can explain how the destroyer was hit by the commercial ship on its starboard side-- normally, the Destroyer with a ship to starboard would need to maintain speed just like the freighter should do and determine whether to pass well in front of or in back of the freighter. Possibilities include: 1 someone just did not see or note on radar the large ship to starboard heading at 15-18 knots on a possible collision course  toward course of the destroyer, 2 there was a miscalculation and the destroyer thought it would cross well in front of the ship (or the ship was going slowly and sped up). The miscalculation could happen if the destroyer was not at the speed the calculations were based on, or slowed down and/or maneuvered  (maybe to avoid another ship). The destroyer may have been on a shakedown cruise with its $21B. refit.