Lt. Nicols was appointed as a Naval Cadet (SSA) for the Royal Canadian Navy on September 12, 1954. He served in the Officer Training Establishment of HMCS Venture for training in 1954. Later, he was appointed as a Midshipman (SSA) for the RCN on September 1, 1956. In this role, he served in HMCS Niagara for pilot training with plate number 1. He also received flight training in USNAS Pensacola, NAAS Saufley Field, NAAS Corry Field, and USNAS Kingsville TX in 1956. He was then appointed as an A/Sub-Lieutenant (SSA) for the RCN on September 1, 1957, and was awarded wings on May 29, 1958.
On March 1, 1958, he was appointed as a Sub-Lieutenant (P) (SSA) for the RCN. He served in various squadrons, including VU-32 Squadron, HU-21 Squadron, and HS-50 Squadron while stationed at HMCS Shearwater and HMCS Bonaventure. He was promoted to Lieutenant (P) (SSA) for the RCN on October 1, 1960, and served as the Operations Watchkeeper and Flight Crew Briefer in HMCS Bonaventure in 1962.
In the years that followed, he served in various roles in different locations, including Watchkeeping Training in HMCS Annapolis in 1964, Navigating Officer and Air Officer in HMCS Annapolis in 1965, and Helicopter Refresher Course in HMCS Shearwater for HU-21 Squadron in 1966. He also served in HMCS Bonaventure for HS-50 Squadron, HMCS Nipigon for HS-50 Squadron, and HMCS St. Laurent for HS-50 Squadron.
In 1969, he served in CFB Shearwater for Aircrew Division as Ground Training Officer, and in 1972, he served as Base Personnel Services Officer in the same location. He served in CFB Portage La Prairie for VT-406 Squadron in 1974. Later that year, he served in HS-443 Squadron in CFB Shearwater and in HMCS Protecteur, HMCS Preserver, and HMCS Athabaskan for HS-443 Squadron Air Detachment.
In 1977, he served in CFB Shearwater for HT-406 Squadron as Course Control and Administration Officer. Finally, he served in CFB Shearwater Base Operations as Operations Duty Officer in 1983, before retiring on February 19, 1994.
Throughout his service, Lt. Nicols flew various aircraft and helicopters, including the Fleet 80 Canuck, C-45 Beechcraft Expeditor, Bell HTL-6 Sioux Helicopter, H04S-3 Horse Helicopter, CH-124 Sea King Helicopter, CH-136 Kiowa Helicopter, and the Grumman Tracker. His logbooks contained a nominal roll list, qualification sheets, aircraft codes, records of flying time, and a helicopter training certificate. SAM.2005.121.43h