Kenneth Cecil Maclure

Kenneth Cecil Maclure, A.F.C., C.D., B.Sc., M.Sc., PhD (Nuclear physics) was born in Montreal on October 14, 1914. He completed high school there and entered McGill University on a full scholarship. He graduated in 1934 with a Bachelor of Science degree in Mathematics and Physics.

In the fall of 1939 he was selected among the top McGill graduates to initiate the training of navigators for the newly planned British Commonwealth Air Training Plan (BCATP). He joined the RCAF and began the first Instructor's Course in navigation at Trenton, Ontario before moving to the Air Navigation School at Rivers, Manitoba.

In 1941 Maclure was posted to the Royal Air Force (RAF) No. 31 Air Navigation School at Port Albert, Ontario where the RAF's chief navigational school had been transferred from England. A recently developed Link Celestial Navigation Trainer had been installed there. It was able to simulate flights at all latitudes, including the polar region. This intrigued him and further stimulated his interest in problems associated with polar navigation.

With his solid background in mathematics and physics and an interest in the basics of air navigation, Maclure quickly grasped the extent of the problem and immediately set about finding answers. His study culminated in a definitive paper on polar navigation which was published in the fall of 1941. While not the first to suggest a grid overlay, he was the first to propose a method for using it effectively. He named it the Greenwich Grid since his proposal involved drawing reference lines parallel to the Greenwich Meridian.

Acknowledging that the magnetic compass was of very little use in the polar region, he suggested that a directional gyroscope could provide a stable and practical steering reference. He then described how the procedure was to be used to maintain a desired heading using the astro-compass, celestial bodies, and a constant scale chart, such as the Polar Stereographic, with the Greenwich Grid overlay. The traditional coordinates of latitude and longitude would continue to be used to identify a geographic location as well as the position of the aircraft.

Because the war demanded all available resources, and very high latitude flights were not a priority at the time, nothing further was made of this highly significant development, although it was a matter of serious discussion at high levels in RAF, RCAF and U.S. military circles. Maclure's paper remained under security wraps until the end of WW II.

In October 1941 he was assigned to oversee navigation training at the BCATP schools in Western Canada. The following year, Maclure, then a Squadron Leader, attended the first Specialist Navigation Course in England. He then returned to Canada where he held senior navigation training positions at Air Force HQ and No. 3 Training Command in Montreal. He was now an Acting Wing Commander.

In November 1944 at the request of the RAF, Maclure again went overseas to serve as Director, Test and Development at the Empire Air Navigation School (EANS) in Shawbury, which was considered the leading allied air navigation school at the time. Planning now began, under his guidance, to test the Grid Navigation System.

In May 1945 a specially modified Lancaster bomber aircraft, named "Aries", undertook a series of flights to both the North Geographic and North Magnetic Poles. These flights, involving 110 hours flying time between May 17 and 26, established the Greenwich Grid as a fully practical and safe routing navigation technique. One of the flights also established that the North Magnetic Pole was about 480 kilometers north-northwest of its charted position, further emphasizing the failure of the magnetic compass as a steering reference.

To obtain his instrument readings, Wing Commander Maclure worked under extreme conditions, spending up to nineteen hours at a time confined to the rear of the Lancaster's fuselage where inside temperatures were almost as cold as outside - often down to minus 65 degrees.

On a flight destined for Whitehorse, Yukon the Aries stopped briefly at the RCAF Central Navigation School in Rivers, Manitoba, where the staff was briefed on the success of the Aries flights and the utility of the Greenwich Grid. Following a stopover in Whitehorse, a direct flight was made back to the EANS at Shawbury, once again successfully employing the Greenwich Grid navigation technique. Thus Maclure was the first Canadian to fly over the North Geographic Pole.

Upon completion of the Aries flights, Maclure received the Air Force Cross from the RAF in recognition of his contributions as the senior navigator directing all aspects of the Aries research flights. The U.S. Institute of Navigation honoured him with their prestigious Thurlow Award in recognition of his "outstanding contribution to the science of navigation" in 1945. He was the first recipient of this award.

Dr. Maclure's paper on "The Arctic Flights of the Lancaster' Aries", May 1945, was published as the first article in the very first issue of the US Institute of Navigation Journal in March 1946. This was a singular tribute to his work.

On his return to Canada in 1946, Maclure was seconded to the Arctic Section of the Defence Research Board to work on arctic navigation problems. At this time, through security declassification and the publicized success of the Aries flights, the Greenwich Grid system had gained wide recognition. His writing and speaking engagements ranged from consulting with the U.S. military on the Greenwich Grid technique to addressing the Royal Geographic Society in the UK on the technical aspects of the Aries polar flights. During this time, other Aries-related articles were published in various journals.

In 1948 Maclure returned to McGill University for post-graduate studies in Physics, and acquired an M.Sc. in 1950, and a Doctorate in Nuclear Physics in 1952. He was elected a Fellow of the Royal Institute of Navigation in 1949.

During the early 1950's, Maclure returned to the field of research as Senior Test Engineer at the Central Experimental and Proving Establishment (CEPE) at RCAF Station Rockcliffe. Promoted to Group Captain in 1958, he served at Air Force Headquarters as Director of Armament Engineering. He was later posted as the Canadian Military Attache to Warsaw, Poland where he served for three years.

When he returned to Canada in 1961, he was again seconded to the Defence Research Board, this time to the Pacific Naval Laboratory at Esquimalt, B.C. as head of the Electro-Magnetic Research Group. He was engaged in acoustic and electromagnetic research in ice-filled waters, a matter of extreme importance to RCAF anti-submarine operations. Unfortunately, because of the military sensitivity of much of his work, his contributions are not widely known outside of the military.

Maclure retired from the RCAF in November 1969, but he continued as head of the Electro-Magnetic Research Group at Esquimalt conducting research in the Arctic on under-sea and ice experiments out of Resolute Bay, NWT. He also served as a part time lecturer in Physics at the University of Victoria. In 1971 he was appointed Chief of Defence Research Staff at the Canadian High Commission, London, a position he held for four years. In 1974 he was elected Vice President of the Royal Institute of Navigation. He returned to Canada in 1975, to the Defence Research Board as senior research and development planning officer. He was elected Fellow of the Canadian Aeronautics and Space Institute (CASI) in 1976. He retired in October 1979 and continued to live in Ottawa.

Group Captain Maclure died suddenly on March 28, 1988 while vacationing in Mexico.

Kenneth Cecil Maclure was inducted as a Member of Canada's Aviation Hall of Fame at ceremonies held in Edmonton, June 4, 2005 at a ceremony held at Edmonton, Alberta.