The Lockheed P-2 Neptune (designated P2V by the United States Navy prior to September 1962) was a maritime patrol and anti-submarine warfare (ASW) aircraft. It was developed for the US Navy by Lockheed to replace the Lockheed PV-1 Ventura and PV-2 Harpoon, and was replaced in turn by the Lockheed P-3 Orion. Designed as a land-based aircraft, the Neptune never made a carrier landing, but a small number were converted and deployed as carrier-launched, stop-gap nuclear bombers that would have to land on shore or ditch. The type was successful in export, and saw service with several armed forces.
The Canadian version of the Lockheed Neptune (P2V7) served as an anti-submarine, anti-shipping and maritime reconnaissance aircraft in the RCAF Maritime Air Command from 1955, replacing the Avro Lancaster maritime aircraft. The Canadian P2V7 was fitted with piston engines, although the Canadian Neptunes, without the underwing Westinghouse J34 jet engine pods which were retrofitted in 1959, similar to those fitted to US Navy variants. Armament included two torpedoes, mines, depth charges, bombs carried internally plus unguided rockets mounted externally underwing. A total of 25 Neptunes served with RCAF Nos. 404, 405 and 407 squadrons until 1960. With the unification of the Canadian Forces in 1968, the Neptune was retired and retroactively re-designated the CP-122. The RCAF Neptune was replaced by the Canadair CP-107 Argus in the same year. Wikipedia and Harold Skaarup web page
Wikipedia Neptune Maritime Patrol
RCAF P2V-7 Neptune Serials - Kestrel Publications