The UH-2 was introduced in time to see action in the Tonkin Gulf incident in August 1964. The Seasprite's principal contribution to what would escalate into the lengthy Vietnam War between the Soviet-backed North Vietnamese and the United States-backed South Vietnamese, was the retrieval of downed aircrews, both from the sea and from inside enemy territory. The type was increasingly relied upon to perform the retrieval mission as the conflict intensified, such as during Operation Rolling Thunder in 1965. During October 1966 alone, out of 269 downed pilots, helicopter-based SAR teams were recorded as having enabled the recovery of 103 men.