Kawasaki P-2J

Anti-submarine warfare and maritime patrol aircraft developed for the Japan Maritime Self Defense Force.

Kawasaki P 2J Neptune ‘4782 82’ Japanese Maritime Self Defense Force
photo: Alan Wilson

The P-2J is a twin-engined long-range maritime reconnaissance aircraft manufactured by Kawasaki Aerospace Company for the Japan Maritime Self Defense Force as a substitute to acquiring the larger and costly P-3 Orion. The P-2J has been known as a marvelous anti-submarine warfare aircraft that played on a part of a major anti-submarine weapon and left a legacy in an era of changes.

1966 to: 1979


2x Ishikawajima-Harima T64-IHI-10
2,850 horsepower
Max Cruise Speed:
350 knots
648 Km/h
Approach Speed (Vref):
Travel range:
2,400 Nautical Miles
4,445 Kilometers
Fuel Economy:
Service Ceiling:
30,020 feet
Rate of Climb:
1797.8 feet / minute
9.13metre / second
Take Off Distance:
Landing Distance:
Max Take Off Weight:
34,020 Kg
75,000 lbs
Max Landing Weight:
Max Payload:
14,742 Kg
32,500 lbs
Fuel Tank Capacity:
Baggage Volume:
Seats - Economy / General:
12 seats
Seats - Business Class:
Seats - First Class:
Cabin Height:
Cabin Width:
Cabin Length:
Exterior Length:
29.23 metre - 95.90 feet
Tail height:
8.93 metre - 29.30 feet
Fuselage Diameter:
Wing Span / Rotor Diameter:
30.87 metre - 101.28 feet
Wing Tips:
no winglets
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Kawasaki P-2J Production

In 1963, Kawasaki engineers attempted to upgrade the performance of the ancient SP-2H Neptune and lengthened its service life; they had thought to convert the Neptune into a turboprop-powered aircraft. The new version was meant to utilize several advanced systems used in the Lockheed P-3 Orion.

In May 1965, a standard plan was prepared for the P2V-7 “Kai”, short for the Japanese word “kaizo” that means modification. Initially given the designation GK-120, Kawasaki later renamed the aircraft to P-2J during production. Construction of the prototype started by mid-1965 with the conversion of P2V-7 number 4637. On October 5 1965, flight testing of the jet engines started.

On July 21 1966, the first P-2J converted from a P2V-7 took its maiden flight. On November 14 1966, it was delivered to the Japan Maritime Self Defense Force.

There were eighty-three P-2Js built by Kawasaki in total. On October 7 1969, the first production model was delivered to the Japan Maritime Self Defense Force and designated to the 51st FS for tests.

On February 27 1971, the 1st FS finished its transition from P2V-7s to P-2Js, and on April 28 1971, the 2nd FS acquired its first turboprop aircraft. The P-2J slowly took over the P2V-7 aircraft in service. On March 14 1979, the last aircraft was delivered to the Japan Maritime Self Defense Force.

The Kawasaki P-2J retired in 1996.

Kawasaki P-2J Design

The standard design of P-2J was based from the P2V-7, lengthening the aircraft by 1.3 meters, adding a tactical coordinator seat with the capability to attach anti-submarine equipment on the flight deck and has been improved to let the crew to walk around 0.3 meters down the course of the flight deck.  The aircraft is also installed with air conditioning system to keep the performance of electronic equipment in the humid waters of Japan and to enhance the habitability of the crew. Additionally, an ample revision was made on the steering system. Aside from the 20 percent increase on the area of the rudder, the steering angle was modified from ± 21 ° to ± 25 °, a spring tab was also built to decrease the steering force.

The Kawasaki P-2J can accommodate up to twelve crew members. AN/APS-80 search radar was installed in a smaller radome, and a more compact and improved avionic system was also installed. The lighter avionics load allowed higher fuel capacity on the aircraft. The mid-mounted wings of the P-2J each had an engine nacelle along the leading edge. The wings showed a distinguishable amount of dihedral with tips that carry mission-related equipment. Pods were also attached below each wing just outboard of each engine nacelle. The P-2J has a wingspan of 30.87 meters, wing area of 92.9 square meters and was fitted with two wheels on the main landing gear.

Kawasaki P-2J Engine

The Kawasaki P-2J is powered by two Ishikawajima-Harima T64-IHI-10 turboprop engines with a maximum thrust of 2,850 horsepower each, using three-bladed constant speed fully-feathering reversible-pitch propellers. It has a 2-meter length and a 0.58-meter diameter. It features a high overall pressure ratio, yielding a low specific fuel consumption. The axial compressor has fourteen stages required to provide the needed overall pressure ratio. Compressor handling is aided by four rows of variable stators. It has a 2-stage high power turbine and a 2-stage free turbine.

The Ishikawajima-Harima J3-IHI-7C booster turbojet engines has a maximum thrust of 3,100 lbf each. The axial flow turbojet has a length of 1.66 meters without tailpipe and diameter of 0.62 meters. It has an eight-stage axial compressor, annular combustion chamber with thirty fuel supply pipes and vaporizer tubes, and a single-stage axial-flow turbine.

Kawasaki P-2J Performance

The Kawasaki P-2J has a maximum speed of 350 knots, cruising speed of 200 knots and stall speed of 87 knots. It has a range of 2,400 nautical miles, service ceiling of 30,020 feet and a rate of climb of 1,797.8 feet per minute.

The aircraft has a maximum take off weight of 34,020 kg and maximum payload of 14,742 kg.