In 1952, at 18 years of age Merlyn became a pilot to assist his father George with their commercial fishery at the West Channel fishing village in Hay River, NWT. It was the beginning of what was to become a lifetime career in aviation where Merlyn amassed more than 25,000 flying hours, half of them on DeHavilland Single Otter aircraft. Most of his total flying experience accumulated was on float or ski equipped aircraft. In 1962 Merlyn and his wife Jean started Carter Air Services Ltd. Since then he never piloted an airplane he did not own, and for fifty years Merlyn was instrumental in assisting dozens of aspiring young men to start their careers as commercial pilots. Some such as Joe McBryan (Buffalo Airways), Perry Linton (Nahanni Air), Darcy Fleming (Boeing 747 Captain – Japan Air Lines), Clay Gamble (Air Canada Captain), and others that started flying with Merlyn went on to make lifetime careers for themselves in aviation.
During the early 1960’s, to supplement their fledgling aviation business and to care for a growing number of tourists wanting to fish in Northern Canada, Merlyn purchased a Mark IV Norseman. (Single and Twin Otters were added later). He set up tent camps near the mouth of the Tree River on the Arctic Ocean, including other excellent fishing locations such as the Coppermine River, Nonacho Lake, Point Lake, McKay Lake, Thubun Lakes, Gagnon Lake, and Brabant Island on the Mackenzie River. In so doing, Merlyn and his wife Jean became among the early pioneers of tourism in the Northwest Territories. Eventually their several sports fishing camps developed into one main camp at Nonacho Lake, capable of accommodating more than 30 fisherman at one time. For more that forty years sports fishermen from around the world have enjoyed fishing at camps or lodges that he started, operated and serviced with Carter Air Services aircraft.