Canadair presented two proposals, the CL-28 also based on the Britannia, which was accepted, and a lowest cost design called the CL-33 which was described as a fat Lancaster.

The hybrid design, initially referred to as the 'Britannia Maritime Reconnaissance', or 'Britannia MR', was derived from the Bristol Britannia airliner, having the same wings, tail surfaces and landing gear except for being "Americanized" – meaning that it used the same general design, but changed from British materials, dimensions and standard parts to American ones.

[5] The fuselage was completely redesigned by Canadair, going from the pressure cabin used in the Britannia to an unpressurised one with two 18 ft (5.5 m) long bomb bays fore and aft of the wings.

A large amount of equipment was carried, including: search radar, sonobuoys, electronic counter measures (ECM), explosive echo ranging (EER) and magnetic anomaly detector (MAD).

An Argus flown by 407 Maritime Patrol Squadron on 1-2 October 1959 held the Canadian military record of slightly over 31 hours for the longest flight by an unrefuelled aircraft, while covering a distance of 4,570 mi (7,350 km) from RNZAF Base Ohakea in New Zealand to Naval Air Station Barbers Point in Hawaii, before continuing across the rest of Pacific and most of Canada.

Data from The Encyclopedia of World Aircraft[29]General characteristics Performance Armament (Maximum load of 8,000 lb (3,600 kg)) Avionics