Adamson grew up in Fairlie before attending Timaru Boys' High School, where he was a boarder apart from his final year, when he commuted daily on his motorcycle.
He then joined the Royal New Zealand Air Force in 1961, where he served as a pilot flying Austers and Harvards.
[1] In 2002, he caused "unprecedented controversy" when he criticised the government for disestablishing the air combat force.
[1] In the 1979 Queen's Birthday Honours, Adamson was awarded the Air Force Cross.
[4] In the 1999 New Year Honours, he was appointed a Companion of the New Zealand Order of Merit.