Like many aircraft with a relatively long production run, the original P2V design saw numerous changes from model to model. Successive Neptune models introduced more powerful engines, improved capability and gradually removed defensive armament in favor of more anti-submarine electronics. Lockheed would build 7 major variants of the Neptune beginning in 1946. The last of the 1050 Lockheed built Neptunes would leave the Burbank production line in 1962.
