In August 1959, "Thetis Bay" was serving with the 7th Fleet when floods in Taiwan left thousands homeless. On the 12th, she was ordered to proceed from Hong Kong to Taiwan and use HMR(L)-261's (USMC) 21 large troop-carrying helicopters to aid the flood victims. By the end of the assistance operation, at noon of the 20th, the ship had delivered a total of 1,600,540 pounds of supplies to the Taiwanese. In addition, HMR(L)-261's helicopters had carried 850 passengers to and from various sites in the flooded area.