World's Largest Tanker Launched At Barrow-In-Furness - Spyrios Niarchos entering the water during the launching at Barrow-in-Furness, today December 2. The world's biggest oil tanker, the 47,750-ton Spyrios Niarchos, was launched at Barrow-In-Furness, today December 2. Vickers Armstrong built the tanker for Greek shipping magnate Stavros Niarchos, who attended the launching. Flying the Greek flag, the ship will carry crude oil from the Persian Gulf to refineries in the United Kingdom. The new tanker is 757 feet long, and turbines of 20,000 horsepower will drive it at a maximum speed of 17 knots. December 2, 1955. (Photo by Associated Press Photo).