A product tanker weighing 47,400 tons sailed a distance of 280nm having its engine shut off using only wind and sea currents to navigate through the sea. The tanker made it to the discharge port in time. but by stopping the main engine for 3-4 days, savings of 27 tons of fuel were made. So it appears that sometime traditional methods of navigation at sea may be more economic/fuel efficient compared to proposed technological improvements. Of course this cannot happen everyday but such an incident is worth mentioning especially during these times were everyone seems to be in panic of cutting costs and saving more fuel.
Officer of the Watch 