The s were succeeded by the longer . Assurance had an overall length of 224feet and a length of 203inchesft6inchesin (ftin) at its waterline. It had a beam of 43feet and a draft of 15feet. The surveillance ship had a displacement of 1600t at light load and 2301t at full load. It was powered by a diesel-electric system of four Caterpillar D-398 diesel-powered generators and two General Electric 550PS electric motors. This produced a total of 3200PS that drove two shafts. It had a gross register tonnage of 1,584 tons and a deadweight tonnage of 786 tons.[1]
The Stalwart-class ocean surveillance ships had maximum speeds of 11kn. They were built to be fitted with the Surveillance Towed Array Sensor System (SURTASS) system. The ship had an endurance of thirty days. It had a range of 3000miles and a speed of 11kn. Its complement was between thirty-two and forty-seven. Its hull design was similar to that of the s.[1]
USNS Assurance was a Stalwart-class modified tactical auxiliary general ocean surveillance ship of the United States Navy. Stalwart-class ships were originally designed to collect underwater acoustical data in support of Cold War anti-submarine warfare operations in the 1980s.
In 1999, ex-USNS Assurance was transferred to Portugal and is now NRP Almirante Gago Coutinho survey ship.[2]