Lockheed Aircraft Company
Lockheed P2V Neptune
Number built 1,177  Introduction date March 1947 First flight 17 May 1945

The Lockheed P-2 Neptune (designated P2V by the United States Navy prior to September 1962) is 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 (using JATO assist), 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.

Normal crew access was via a ladder on the aft bulkhead of the nosewheel well to a hatch on the left side of the wheel well, then forward to the observer nose, or up through another hatch to the main deck. There was also a hatch in the floor of the aft fuselage, near the sonobuoy chutes.

Operational history

U.S. Navy service

Early Cold War

Prior to the introduction of the P-3 Orion in the mid-1960s, the Neptune was the primary U.S. land-based anti-submarine patrol aircraft, intended to be operated as the hunter of a '"Hunter-Killer" group, with destroyers employed as killers. Several features aided the P-2 in its hunter role:

• Sonobuoys could be launched from a station in the aft portion of the fuselage and monitored by radio
• Some models were equipped with "pointable" twin .5 in (12.70 mm) machine guns in the nose, but most had a forward observation bubble with an observer seat, a feature often seen in images.
• The AN/ASQ-8 Magnetic Anomaly Detector was fitted in an extended tail, producing a paper chart. Unmarked charts were not classified, but those with annotations were classified as secret.
• A belly-mounted AN/APS-20 surface-search radar enabled detection of surfaced and snorkeling submarines at considerable distances.