Otter 346 was delivered to the United States Army on 20th November 1959 with serial 59-2209 (tail number 92209). It was assigned to the 17th Aviation Company, Fort Ord, California. In June 1964 it joined the Otter Transition School, also at Fort Ord, where it served until February 1966 when it went to Vietnam, joining the 18th Aviation Company. It is mentioned in the unit's history: “On 10th March 1969 Captain Robert Spieldenner, Assistant Section Leader, was flying 'Reliable 209' from Pleiku to Phu Hiep AAF. Upon landing at Phu Hiep, the aircraft bounced hard and Captain Spieldenner was unable to recover and the aircraft landed hard on the second bounce, causing damage to both main tyres and the tail wheel motor housing”. The damage was repaired and the Otter continued in service with the 18th Aviation Company until February 1971, when the Company was disbanding. John Pinkerton was crew chief on 92209, and recalls his last flight on the aircraft on 25th February 1971 from Tuy Hoa back to the Company headquarters at Qui Nhon.

In March 1971 the Otter was entrusted to the 388th Transportation Company at Vung Tau for storage, but between May and July 1971 it flew again, for the 165th Combat Aviation Group, returning to the 388th Transportation Company at Vung Tau, the unit responsible for the disposal of all Army Otters in Vietnam. In September 1971 it was handed over to the Government of Cambodia, one of 18 Otters transferred to that country. Their operation was short lived and the fate of this Otter can only be described as “withdrawn from use and scrapped”.