Heavy tank
The Char 2C was one of the largest tanks ever produced. At the start of World War II, France and the Soviet Union were the only countries to have inventories of heavy tanks, such as the Char B1, T-35, and KV-1. The Matilda II was designed under the British infantry tank concept which is similar to the heavy tank having thick armor and weighing more than their other tanks. It’s usually separate because they have less firepower with their cruiser tanks (comparable to mediums) at the time having the same main armament but more machine guns. Later war examples were the German Tiger I and II, as well as the Soviet IS series. Note that "heavy" versus "medium" is more a question of tactical roles than weight; the Panther, for example, was a "medium" tank that outweighed most Allied "heavy" tanks.
History of the oil tanker
Ludwig had started Universe Tankships in 1947 and began building larger tankers in his Welding Shipyards. The "Bulkpetrol" of 30,000 long tons was the largest tanker of its time. Four of the five Bulk class tankers sank, likely because welding technology was not yet fully understood. As larger ships could not be constructed in the yard at Norfolk, Virginia, Ludwig went to Japan where he introduced the block construction method at the Kure Naval Yard. Here, in 1952, he built the "Petrokure" of 38,000 long tons. That same year, Onassis had a tanker of 45,000 long tons built and also Niarchos had supertankers built. Both Onassis and Niarchos claimed to be the largest independent tanker owner in the world.