100 Years of Maritime Air Operations

Birthplace of Maritime Patrol In Canada

            Founded in 1918, 12 Wing Shearwater will celebrated its 100thanniversary in 2018. 12 Wing Shearwater is one of the oldest military airfields in Canada, second only to 16 Wing Borden. Shearwater’s varied and colourful history reflects the evolution of flying in Canada and indeed the growth of Canada’s Air Force. Shearwater was originally created as a seaplane base in August 1918, when the small promontory in Halifax harbour’s Eastern Passage, known as Baker Point, became U.S. Naval Air Station Halifax. It subsequently became an air station for the Canadian Air Force, the Royal Canadian Air Force (RCAF) and the Royal Canadian Navy (RCN) known as HMCS Shearwater.  With the integration of the armed forces in 1968, Shearwater was designated a Canadian Forces Base (CFB), and re-named 12 Wing Shearwater[1]following Air Force restructuring in 1993. Shearwater has been a home for Canada’s air squadrons for the past 100 years, continuously supporting flying operations longer than any other Canadian military air base. By virtue of its coastal location, 12 Wing Shearwater has been inextricably linked to the defence of the air and sea approaches to Atlantic Canada. In fact, it was the threat by sea that provided the original raison d’ etre for the Wing. Today, Shearwater provides RCAF maritime helicopter detachments to RCN ships in support of UN and NATO naval operations around the world.

The Birth of Maritime Aviation in Canada

During the First World War, German submarines operated between Newfoundland and Nova Scotia, particularly in the waters off the eastern and southern shores of Nova Scotia. In peace and even more so in war the amount of shipping entering and leaving the Gulf of St. Lawrence and using the harbours of Nova Scotia was enormous. Vessels sailing singly or banded together in convoys were departing in rapid succession from ports in eastern Canada, especially from Halifax and Sydney, laden with troops and supplies to support British and Canadian armies in Europe. Moreover, many transatlantic ships bound for or departing from the northeastern United States passed through the outer fringes of these waters. Therefore, both the Canadian and American governments were vitally interested in protecting these shipping lanes.

            Until 1915, no German submarines operated in Canadian waters. The submarine threat wasn’t taken serionsly until 8 October 1916 when German submarine U-53 sank five merchantmen off Nantucket. The appearance of U-53 prompted the British Admiralty to warn Canada that anti-submarine patrols off its coast should be strengthened. A subsequent Canadian proposal to base anti-submarine air patrols at Halifax and Cape Breton Island was welcomed by the Admiralty and sent Commander Sneddon, Royal Naval Air Service (RNAS), to Canada to investigate the feasibility of such patrols. Sneddon recommended that a small seaplane force, divided between Halifax and Sydney, NS be formed and that required aircraft be built in Toronto by Canadian Aeroplanes Ltd. The Canadian Cabinet rejected Sneddon’s report on the grounds of excessive costs ($2.5 million), the diversion of skilled labour from other wartime priorities, and concern over seasonal weather changes limiting the effectiveness. 

            By 1917 the success of east bound convoys sailing from Halifax and Sydney compelled the Germans to shift the focus of their operations. About the same time they had developed large ocean-going submarines, capable of staying at sea for three months or more and mounting 6-inch deck guns. Suddenly the Canadian coast became a vulnerable target area. The Admiralty warned Ottawa of these latest developments and the Canadian Naval Service immediately attempted to strengthen its patrol force. However, no additional ships were available and it was decided that aircraft operating from shore bases were the best means to protect merchant shipping in Canadian waters. But where were the aircraft to come from? The Admiralty had no surplus and the only possibility seemed to be the United States Navy (USN). 

Meanwhile the German threat was so acute that the Admiralty renewed its warning and offered a preliminary plan for aircraft patrols. Shortly thereafter, British and American Admirals convened a conference in Washington, which included Captain Walter Hose, the Royal Canadian Navy’s (RCN) Captain of Patrols on the east coast. The conference settled two points: first, air stations should be established at Halifax and Sydney: secondly, that the United States would supply these stations with pilots, seaplanes, airships and kite balloons until the embrionic Royal Canadian Naval Air Service (RCNAS) was trained and ready to take over. On 23 April 1918, it was also agreed that the United States would take responsibility for coastal patrol and anti-submarine work as far east as western Nova Scotia and that assigned American forces would be placed under operational control of the RCN. Because Canada had no officers experienced in maritime air operations, the Admiralty appointed Lieutenant Colonel Cull, Royal Air Force (RAF) (formerly Wing Commander RNAS), to overall command of the air patrols. (On 1 April 1918, the RNAS and the Royal Flying Corps were amalgamated to form the RAF).

            On 5 June 1918, after following rather ineffectually in the wake of the Admiralty and the USN, Canadian authorities finally approved establishment of two air stations. Cull arrived from England in July and approved the seaplane base just south of Dartmouth, NS, but moved the Sydney seaplane base to the western side of North Sydney. Despite the lateness of the season, Cull persuaded the USN to implement the April agreement. The Canadian government was to furnish the site and buildings and all ground equipment, while the American government was to provide the aircraft and the personnel to operate them as well as the operating expenses. British and Canadian naval officers were ultimately responsible for control of the stations and for operations, however, supervision and direction of the officers was to be the responsibility of the U.S. Navy. The Americans created the office of Commanding Officer, U.S. Naval Air Forces, Canada and detailed Lieutenant R.E. Byrd USN, later an Admiral renowned for his polar exploits, to the new command. Additionally, Lieutenant Byrd was ordered to assume direct command of U.S. Naval Air Station Halifax and to act as liaison officer between the American and Canadian governments in naval aviation matters.

            Although progress up to this point in establishing the air patrols was gratifying, it was not rapid enough to meet the alarming situation that developed in the first week of August 1918 when U-156 sank six vessels southeast of Nova Scotia. The submarine also captured a large Canadian fishing boat and mounted a gun on its deck that was used to wreck havoc among Canadian fishermen. At the same time numerous mines, laid by the submarine, were discovered along the Nova Scotia coast. It was crucial to commission the Canadian air stations into operation as soon as possible. All haste was made in shipping equipment and supplies to Halifax that were essetial for operations. Lieutenant Byrd arrived at his new base 15 August 1918. Crates containing the first two Curtiss HS-2L seaplanes arrived in Halifax by train 17 August and were barged across the harbour to the Dartmouth air station and hauled up on the beach using logs for rollers. The first aircraft was assembled and successfully test flown two days later and the first operational patrol was flown 25 August 1918; maritime patrol aviation in Canada was born. 

            During the first few weeks no bombs had yet reached Dartmouth, however, the submarine situation was so serious that depth charges were substituted for bombs with the intention of dropping them by hand on any hostile submarine. Lieutenant Byrd eventually established a detachment of six HS-2L flying boats and several kite balloons to conduct anti-submarine patrols off the approaches to Halifax harbour and a second detachment of six HS-2L’s at North Sydney. In forming the general operating policy for the aerial patrols, it was agreed not to attempt routine patrols at either Halifax or North Sydney, but to keep two seaplanes solely for escort work and one seaplane at each station for emergency anti-submarine duty. Without interfering with this schedule, as many supplementary patrol flights as possible were also to be flown at each station at the times and locations deemed most likely to produce results. Operations began in earnest the week of 7 September 1918 during which seven escort flights and ten patrol and other flights were made. Emergency flights were made whenever circumstances demanded and all convoys were escorted for a distance of 60 to 75 miles (100 to 125 km) to sea.  There was a total of 200 patrol and other flights during the USN deployment, accumulating approximately 400 flying hours.

After the First World War ended in November 1918 the RCNAS was disbanded and the U.S. Navy personnel departed the bases at Dartmouth and North Sydney and returned home.  Now promoted, Colonel Cull’s final duty was to accompany the Deputy Minister of the Canadian Naval Service to Washington to settle the division of expenses between the two countries. The Canadian government agreed to purchase all American ground equipment at the two stations; in exchange, the United States donated to Canada 12, HS-2L flying boats, 26 Liberty aircraft engines and four kite balloons. Canada’s first venture into maritime patrol aviation had cost a total of  $811,168 for bases, equipment and personnel. The American donation was valued at $600,000 and the flying boats were to give much valuable service to Canada in the years to come. 

This small fleet of maritime patrol aircraft and the few buildings which had been built by the Canadian government to support Lieutenant Byrd’s detachment were the beginning of what became RCAF Station Dartmouth on 1 April 1924, a forerunner of today’s 12 Wing Shearwater.  

Ernest Cable

MAVA  Historian


[1]12 Wing Shearwater preserves both RCAF and RCN heritage. 12 reflects 12 Group of the RCAF’s Eastern Air Command in Halifax during the Second World War and Shearwater reflects the station’s RCN name dating back to 1 Dec 1948.

Curtiss HS-2L in Canadian Colours