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Lockheed P-2 Neptune

Lockheed · Maritime Patrol / ASW · USA · Early Jet (1946–1969)

The Lockheed P-2 Neptune was an American twin-engine maritime patrol aircraft — the U.S. Navy's principal land-based maritime patrol + ASW aircraft of the 1950s-1970s + the predecessor of the later P-3 Orion. Lockheed designed the Neptune in 1944-1947; first flight 17 May 1945. About 1,181 Neptunes were built between 1946 and 1962 at Lockheed Burbank + Kawasaki Heavy Industries (Japan). The aircraft served U.S. Navy + Royal Australian Air Force + ~10 export operators 1947-1984.

The P2V-7 (most-numerous variant) used 2 × Wright R-3350 radial engines (3,500 hp each) + 2 × Westinghouse J34 turbojets (3,250 lbf each) in supplementary wingtip pods — a unique "piston + jet" hybrid powerplant configuration that improved takeoff + emergency-power performance. Maximum speed 580 km/h, range 5,930 km, endurance 14 hours, service ceiling 7,260 m. Armament: ASW torpedoes + depth charges + mines + nuclear depth bombs (Mk 90 Betty). Crew: 7-9.

Neptune service spanned U.S. Navy maritime patrol + ASW 1947-1970, RAAF maritime patrol 1951-1977 (P2V-5/7 + Japanese-built P-2J). Famous events: a Navy Neptune launched from USS Coral Sea on 1 March 1949 — the first jet-assisted-takeoff of a multi-engine aircraft from a carrier deck + demonstration of Navy nuclear-strike role. Japanese Kawasaki P-2J (P-2 derivative with turboprop engines) served JMSDF 1968-1991. About 25 Neptune airframes survive in 2026 — including airworthy examples at the Mid-Atlantic Air Museum.

For Kids — a shorter, friendlier version

The Lockheed P-2 Neptune was an American patrol plane. It flew for the Navy starting in 1947. Its job was to watch over the ocean and look for enemy submarines.

The Neptune had a special engine setup. It used two large piston engines plus two jet engines on the wingtips. This mix gave it extra power for takeoff and emergencies. No other patrol plane looked quite like it!

The Neptune could fly for up to 14 hours without stopping. That is longer than most school days! It had a crew of seven to nine people on board. They watched the sea below using special gear.

About 1,181 Neptunes were built between 1946 and 1962. They were made in both America and Japan. Many countries flew the Neptune, including Australia. The plane served for a very long time — all the way until 1984.

One Neptune made history in 1949. It took off from a Navy aircraft carrier called USS Coral Sea. This was a big deal because the plane was not made to take off from ships. It showed just how versatile the Neptune really was.

Fun Facts

The P-2 Neptune could stay in the air for 14 hours — longer than a cross-country road trip!
It had four engines total: two big piston engines and two jet engines on the wingtips.
The Neptune was faster than a race car, reaching speeds of about 360 miles per hour.
More than 1,181 Neptunes were built over about 16 years.
A Neptune once took off from an aircraft carrier, something it was never originally designed to do.
The Neptune is larger than a city bus, with a wingspan stretching over 31 meters.
Japan helped build Neptunes at a factory called Kawasaki Heavy Industries.
Australia flew the Neptune for over 25 years, using it to patrol the ocean.

Kids’ Questions

What did the P-2 Neptune do?

The Neptune was a patrol plane for the Navy. It flew over the ocean looking for enemy submarines. It could carry torpedoes and depth charges to stop them.

Why did it have both piston and jet engines?

The jet engines gave the Neptune extra power when it needed to take off quickly or in an emergency. The big piston engines kept it flying for a long time on patrol. Together they made a great team!

How many people flew on a Neptune?

A Neptune carried a crew of seven to nine people. Each person had an important job to do. Some flew the plane while others watched for submarines below.

Is the P-2 Neptune still flying today?

No, the Neptune stopped serving in military forces by 1984. The Navy later replaced it with a newer plane called the P-3 Orion. Some old Neptunes are kept in museums today.

Variants

P2V-1 through P2V-7 (basic): Standard production. About 1,051 built at Lockheed.
Kawasaki P-2J (Japanese licence): Japanese turboprop derivative. ~83 built for JMSDF.

Notable Operators

U.S. Navy (1947-1970): Principal user. ~700 Neptunes in maritime patrol + ASW + nuclear-strike roles.
RAAF (1951-1977): 12 Neptunes for Australian maritime patrol.
10+ export operators: Argentina + Brazil + Canada + France + Netherlands + Portugal + UK + others.

Frequently Asked Questions

Was the Neptune carrier-launched?

Briefly. The U.S. Navy launched a modified P2V-3C Neptune from the carrier USS Coral Sea on 1 March 1949 using JATO (jet-assisted takeoff) bottles — the first multi-engine aircraft to launch from a carrier deck. The mission demonstrated Navy nuclear-strike role from carriers (the Neptune could carry a Mk 4 atomic bomb). The Neptune was too large for routine carrier operations + landed at land bases after launch; the technique was an emergency wartime role only.

Sources

Wikipedia — Lockheed P-2 Neptune