CP-107 Argus
RCAF Argus (foreground) and USN Lockheed P-2 Neptune
Role	Maritime patrol aircraft Type of aircraft
Manufacturer	Canadair
Designer	Tom Harvie [1]
First flight	28 March 1957
Introduction	1957
Retired	1982
Primary users	Royal Canadian Air Force Canadian Forces
Produced	1957- 1960
Number built	33
Developed from	Bristol Britannia

The Canadair CP-107 Argus (CL-28) was a marine reconnaissance aircraft designed and manufactured by Canadair for the Royal Canadian Air Force (RCAF). In its early years, the Argus was reputedly the finest anti-submarine patrol bomber in the world.^[2] The Argus served throughout the Cold War in the RCAF's Maritime Air Command and later the CF's Maritime Air Group and Air Command.

Canadair began work on the CL-28 in April 1954 and at the time it was the largest aircraft built in Canada. The hybrid design, initially referred to as the 'Britannia Maritime Reconnaissance', or 'Britannia MR', was derived from the Bristol Britannia transport, having the same wings, tail surfaces and landing gear except for being "Americanized" – meaning that it used the same general design, but changed the British materials and standard parts for North American ones.

The fuselage was completely redesigned by Canadair, going from the pressure cabin of the Britannia to an unpressurised one with bomb bays fore and aft of the wings. The powerplant was also changed from the Bristol Proteus turboprop engines to Wright R-3350 compound (piston) engines, which had lower fuel consumption necessary for extended missions at low level. At the design stage the other possible engine was the Napier Nomad, another turbo compound engine, although the Nomad was later cancelled.

From July 1960, a CP-107 Argus underwent hot weather testing at Eglin AFB, Florida.

Since the Canadian climate is comparatively cool, even in mid-summer, a team of 35 RCAF officers and airmen have come to Eglin for six weeks to evaluate the performance of their four-engined Argus patrol craft in a hot-weather environment. Squadron Leader Garnet W. Ovans pointed out they could have tested the Argus in a much warmer location, 'but we picked Eglin because it also had the necessary humidity range, and especially because of the extensive testing facilities here. The APGC project officer for the test of the Argus is Major Charles E. Dougan, of the Directorate of Strategic Systems Test. While at Eglin, the 35-man RCAF crew will collect high-temperature performance data on the Argus, including fuel consumption rates, takeoff and landing distances, maintenance techniques, and functional checks of the armament systems.^[3]

The Argus replaced the RCAF Lancaster and Lockheed P-2 Neptune aircraft types previously flown in the maritime roles. One of the most effective anti-submarine warfare (ASW) aircraft of its day, the Argus was a mainstay for the RCAF. A large amount of equipment was carried, including: search radar, sonobuoys, electronic counter measures (ECM), explosive echo ranging (EER) and magnetic anomaly detector (MAD). Up to 8,000 lb (3,632 kg) of weapons could be carried in the bomb bays, including torpedoes, bombs, mines and depth charges.

A flight crew of 15 consisting of three pilots, three navigators (Observer Long range), two flight engineers and six radio officers (observer rad) until the early 1960s when the crew included both commissioned officers (tactical navigator/radio navigator) and non commissioned officers (observers), the number of which was dependent on the mission. Four crew bunks and a galley were provided to extend the efficiency of the crew on long patrols (average 18 hrs). The CL-28 had an endurance of approximately 26½ hours with full armament. An Argus flown by 407 Maritime Patrol Squadron held the Canadian military record of slightly over 31 hours for the longest flight by an unrefuelled aircraft.^[4]

The principal difference between the Mark I and Mark II was primarily in the different navigation, communication and tactical electronic equipment fitted internally. Externally, the Mk II exhibited a redesigned smaller nose radome and additional ECM antenna above the fuselage.^[5]

The Argus flew its last service mission on 24 July 1981, and was replaced by the Lockheed CP-140 Aurora.

• Argus Mk 1 : Long-range maritime reconnaissance aircraft for the RCAF. This aircraft was fitted with an American APS-20 radar in a chin-mounted radome. (13 built)
• Argus Mk 2 : Long-range maritime reconnaissance aircraft for the RCAF. This aircraft was fitted with a British ASV-21 radar in a chin-mounted radome. (20-built)

 Canada

• Royal Canadian Air Force
  • No. 404 Squadron RCAF
  • No. 405 Squadron RCAF
  • No. 407 Squadron RCAF
  • No. 415 Squadron RCAF
  • No. 449 Squadron RCAF
• Canadian Forces
  • 405 Maritime Patrol Squadron
  • 407 Long Range Patrol Squadron
  • 415 Maritime Patrol Squadron

• 10712 – Argus I on static display at the Comox Air Force Museum in Comox, British Columbia.^[6]
• 10717 – On static display at the Greenwood Military Aviation Museum in Greenwood, Nova Scotia.^[7]
• 10732 – Argus II on static display at the National Air Force Museum of Canada in Trenton, Ontario.^[8]
• 10739 – On static display at the Air Force Heritage Park at Summerside Airport in Summerside, Prince Edward Island.^[9]
• 10742 – Argus II on static display at the Canada Aviation and Space Museum in Ottawa, Ontario.^[10]

Data from The Encyclopedia of World Aircraft^[11]

General characteristics

• Crew: 15

Performance Armament
Max 8,000 lb bombs, depth charges, torpedoes, mines and 3,800 lb air-to-surface missiles and free-fall weapons on underwing hardpoints

• Birth of a Giant, a 1957 short documentary about the plane's development

Related development

• Bristol Britannia
• CC-106 Yukon

Aircraft of comparable role, configuration, and era

• Avro Shackleton
• Canadair CL-44
• Lockheed P-2 Neptune

Wikimedia Commons has media related to Canadair CP-107 Argus.

• Footage of the CP 107 Argus in Operation with the Canadian Armed Forces
• DND - Canada's Air Force - Canadair CP-107 Argus
• RCAF.com - Canadair CP-107 Argus
• Birth of a Giant, a 1957 National Film Board of Canada documentary about the development of the Canadair CP-107 Argus
• "Maritime Britannia" a 1955 Flight article
• "Canadair Argus" A 1957 Flight article by Bill Gunston