Born and raised on the East Coast, Whi (also spelt Phee) Wanoa joined the New Zealand Army in January 1965. Later that year he was selected for service in 1 Ranger Sqn NZSAS. Whi served in Borneo (1966) with 3 Detachment, NZSAS and completed two tours with 4 Troop NZSAS in Vietnam. During his first tour, he was wounded in action on 6 August 1969.
During the mid-1970s Whi spent three years as a CSM with 2/1 RNZIR in Burnham before returning to the NZSAS where he served in a range of roles until 1989.
A respected Parachute Jump Instructor and tracker, Whi passed on his skills to generations of young troopers and officers in the NZSAS and was very highly regarded for his knowledge, bluff sense of humour and his direct speech.