Founded as Orvis Nelson Air Transport (ONAT) but operated only briefly under that name.The airline was a large cargo and passenger charter operator with significant miliary contracts and subsidiary businesses. Their primary market was the Pacific basin. At its height, the Transocean organization included ten companies, making it the first aviation conglomerate and it became the largest supplemental air carrier in the world. Known throughout the industry as the flying airline president, Nelson was the only top executive of a major airline during the late 1940s to hold transport pilot ratings. By the mid-1950s and after acquiring several subsidiary businesses, some of the men closest to Nelson began to express concern that perhaps Transocean had over-diversified. TAL was taken over by United States Overseas Airlines on July 11, 1960. USOA ceased operation on November 30, 1964.