The War Shipping Administration took control of all Inter-Island Steam Navigation's ships, but allowed Hawaiian Airlines to operate under the Army's supervision. The ships that used to supply the islands with its consumer goods, were now devoted to transporting soldiers, munitions, and other war supplies throughout the islands. Kennedy petitioned the CAB to allow Hawaiian to fly these consumer goods on its airplanes, and was granted United States Air Cargo Certificate #1. Hawaiian removed the seats of its three remaining S-43s and lone remaining S-38 to use for cargo flights, allowing its DC-3s to fly the passengers. On March 20, 1942, Kennedy watched as Hawaiian's first air-cargo flight departed to serve the people of Hawaii. On April 1, 1966, Kennedy witnessed the final large milestone of his tenure at Hawaiian, the introduction of DC-9 jets for the inter-island service. During Kennedy's oversight of Hawaiian, he had grown it from a fledgling airline flying 8-seat seaplanes to an airline flying a fleet of modern jet airliners. Kennedy was president of the Inter-Island Steam Navigation Company from February 1933, until it ceased operations in 1947. After WWII, Hawaiian Airlines had both a well established inter-island passenger and air-cargo business. Aloha Airlines began inter-island passenger service in 1946, creating more available seats and fierce competition. The 14 hour overnight steamer voyage from Honolulu to Hilo became an outdated form of transportation, when people and cargo could fly there in an hour and a half. After Kennedy returned home from Stanford, he met Martha Davenport on an Inter-Island steamer while she was vacationing in Hawaii from her home in Chattanooga, Tennessee. They wrote to each other after that vacation, and continued during WWI. On his way home after the war, Kennedy stopped in Chattanooga to marry Martha, and then the two continued to Honolulu together. They lived in a beachfront home near Aina Haina, just east of Honolulu, and had a weekend home in Kahuku, on the North Shore of Oahu. Kennedy was also president of the Coca-Cola Bottling Co. of Hawaii, as well as the Honolulu Chamber of Commerce. Kennedy died of a heart attack April 19, 1968 at his Kahuku beachfront home at the age of 77, ending his tenure as Hawaiian Airline's Chairman of the Board. He is buried at the Oahu Cemetery in Nuuanu.