The Kawasaki P-1 (previously P-X, XP-1) is a Japanese

maritime patrol aircraft A maritime patrol aircraft (MPA), also known as a patrol aircraft, maritime reconnaissance aircraft, or by the older American term patrol bomber, is a fixed-wing aircraft designed to operate for long durations over water in maritime patrol ro ...

developed and manufactured by Kawasaki Aerospace Company. Unlike many maritime patrol aircraft, which are typically conversions of civilian designs, the P-1 is a purpose-built maritime aircraft with no civil counterpart and was designed from the onset for the role. It has the distinction of being the first operational aircraft in the world to make use of a fly-by-optics control system. The P-1 has entered service with the

Japan Maritime Self-Defense Force , abbreviated , also simply known as the Japanese Navy, is the maritime warfare branch of the Japan Self-Defense Forces, tasked with the naval defense of Japan. The JMSDF was formed following the dissolution of the Imperial Japanese Navy (IJ ...

(JMSDF) as a replacement for the

P-3C Orion The Lockheed P-3 Orion is a four-engined, turboprop anti-submarine and maritime surveillance aircraft developed for the United States Navy and introduced in the 1960s. Lockheed based it on the L-188 Electra commercial airliner."Sky-High Expectations for Japan's P-X and C-X Aircraft."
''Kawasaki Heavy Industries Scope Quarterly Newsletter'', No.73. October 2007. In 2001, following its earlier proposal, the Kawasaki Aerospace Company received prime contractor status for the P-X program, as well as the adjacent C-X program for a next generation cargo aircraft; this selection process occurred almost 30 years since the previous large-scale domestic development of an aircraft in Japan. The P-X shares some components with the C-X, later designated as the twin-engined Kawasaki C-2, another indigenously developed aircraft to replace the Kawasaki C-1 and C-130H Hercules

cargo aircraft A cargo aircraft (also known as freight aircraft, freighter, airlifter or cargo jet) is a fixed-wing aircraft that is designed or converted for the carriage of cargo rather than passengers. Such aircraft usually do not incorporate passenger a ...

. Although the P-X and C-X designs were originally independent, it was decided that having common components to both designs would be useful. The JDA mandated that the two aircraft share identical body components; common components include the cockpit windows, outer wings, horizontal stabilizer, and other systems. Internal shared parts include the

auxiliary power unit An auxiliary power unit (APU) is a device on a vehicle that provides energy for functions other than propulsion. They are commonly found on large aircraft and naval ships as well as some large land vehicles. Aircraft APUs generally produce 115& ...

, cockpit panel, flight control system computer, anti-collision lights, and gear control unit. Due to the different roles of the two aircraft, they remain distinctly separate. The sharing of development resources had allowed for a large reduction in overall development costs which, when including the C-2, were reported in 2007 as being . In addition to a level of commonality with the C-2, one proposed derivative of the P-1 is a civilian airliner, the proposed project has typically been referred to as the Kawasaki YPX. If development is pursued, the YPX would make extensive use of technology and components of the P-1, such as the wingbox,

empennage The empennage ( or ), also known as the tail or tail assembly, is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow.Crane, Dale: ''Dictionary of Aeronautical Terms, third e ...

, and

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...

.Govindasamy, Siva
"Kawasaki talks civil."
''Flight International'', 23 September 2008. An indigenously produced

turbofan The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft engine, aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the ''turbo'' portion refers to a gas turbine engine which ac ...

engine, the

IHI Corporation F7 The IHI Corporation F7 is a small turbofan engine developed specifically for the Kawasaki P-1 maritime patrol aircraft by IHI Corporation. Development IHI started development work on the high bypass ratio turbofan engine in 1998, based on the ...

, was also developed to power the P-X.Sobie, Brendan
"IHI backs GE's CF6 engine proposal."
''Flight International'', 27 May 2003. By April 2004, the JDA had completed a successful evaluation of five XF7 research engines, by which point it was viewed as being the sole candidate powerplant for the P-X program. In May 2005, the IHI Corporation received a contract for an additional seven XF-7 test engines from the JDA following the completion of initial tests in December 2004, four of these engines were to equip the first flight test aircraft. The

Full Authority Digital Engine Control A full authority digital engine (or electronics) control (FADEC) is a system consisting of a digital computer, called an "electronic engine controller" (EEC) or "engine control unit" (ECU), and its related accessories that control all aspects of ai ...

(FADEC)-equipped F7 engine had a bypass ratio of 8:1, which was reported as being substantially higher than rivals such as the General Electric CF34-8E. P-8A of VP-5 and Japanese Kawasaki P-1 at NAF Atsugi in 2014

P-8A of VP-5 and Japanese Kawasaki P-1 at NAF Atsugi in 2014

In April 2004, Japan and US extended discussions on potential cooperative efforts on the P-X and

US Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

's Multi-mission Maritime Aircraft (MMA) programmes; options ranged from terminating the P-X program to participate in the US-led MMA program to incorporating some of the MMA's technology onto the P-X to reduce costs. The Japanese Defence Ministry ultimately opted to persist with the P-X program, stating that: "there was a possibility that foreign aircraft would not satisfy the required capability and there was a possibility that foreign aircraft would not meet the required period of introduction...it is necessary to domestically develop the aircraft". In addition to the P-1, studies were also conducted into the use of ship-based UAVs to support maritime aviation activities. Since 2014, Japan has been making approaches to other nations for prospective export sales of the P-1. New Zealand was the first country to which the P-1 had been offered in what had been referred to by a Japanese official as a "one on one fight with Boeing's P-8 patrol plane." The P-1 was offered in conjunction with the C-2 to give New Zealand the advantage of commonality for their patrol and transport aircraft. On 9 July 2018 New Zealand selected the P-8 Poseidon instead. Japanese officials have claimed that the P-1 is a more capable, albeit more expensive, aircraft than the

Boeing P-8 Poseidon The Boeing P-8 Poseidon is an American maritime patrol and reconnaissance aircraft developed and produced by Boeing Defense, Space & Security, and derived from the civilian Boeing 737-800. It was developed for the United States Navy (USN). T ...

; in comparison to the P-8, the P-1 has a greater range, a larger bomb bay, and has been purpose-built for the maritime patrol mission. Prior to 2015, the P-1 was being procured at a typical rate of one or two aircraft deliveries per year; in 2015, this changed to a bulk order for 20 P-1s as part of a measure to cut the aircraft's unit costs. By October 2016, 10 P-1s had been delivered to the JMSDF, with 60 or more aircraft needed to replace Japan's P-3C fleet; production will rise to about five annually.JAPAN AEROSPACE: Kawasaki takes aim at international P-1 deals
– Flightglobal.com, 12 October 2016

Design

The Kawasaki P-1 is a purpose-built

equipped with four engines. The P-1 is powered by four podded IHI F7-10

engines underneath the low-set wings. The four-engine low-wing loading design adopted for the P-1 results in a flight profile with better maneuverability and stability at low-speed, low-altitude flight and allows the aircraft to continue its mission in the event of a single engine failure. As well as greater operational survivability, the high-bypass engines provide for quiet, fuel-efficient operation. The P-1 has reduced transit times in comparison to

turboprop A turboprop is a turbine engine that drives an aircraft propeller. A turboprop consists of an intake, reduction gearbox, compressor, combustor, turbine, and a propelling nozzle. Air enters the intake and is compressed by the compressor. ...

-powered competitors, and the turbofans are quieter, making it more difficult for submerged submarines to detect it acoustically. The P-1 is equipped with many newly developed technologies and features, particularly in terms of its avionics and missions systems. One such key feature is the use of a fly-by-optics flight control system, which essentially replaces standard metal wiring with optical fiber cables. This has the effect of decreasing electro-magnetic disturbances to the sensors in comparison to more common

fly-by-wire Fly-by-wire (FBW) is a system that replaces the conventional manual flight controls of an aircraft with an electronic interface. The movements of flight controls are converted to electronic signals transmitted by wires, and flight control ...

control systems. The P-1 is the first production aircraft in the world to be equipped with such a flight control system."Tim Huxley: Japan's P-1 leads defence export drive."
''IISS Defence and Military Analysis Programme'', 11 September 2015. Various onboard systems are provided by

Honeywell Honeywell International Inc. is an American publicly traded, multinational conglomerate corporation headquartered in Charlotte, North Carolina. It primarily operates in four areas of business: aerospace, building technologies, performance ma ...

, which is the largest non-Japanese supplier to the project, such as the

, environmental and pressurization control systems, ram air turbine,

sonobuoy A sonobuoy (a portmanteau of sonar and buoy) is a relatively small buoy – typically diameter and long – expendable sonar system that is dropped/ejected from aircraft or ships conducting anti-submarine warfare or underwater acoustic resea ...

dispensers and elements of the avionics. HPS-106 radar for Kawasaki P-1 patrol aircraft

The P-1 is equipped with various sensors to enable the aircraft to perform its primary purpose of detecting

submarine A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. The term is also sometimes used historically or colloquially to refer to remotely op ...

s and surface vessels; these include the

Toshiba , commonly known as Toshiba and stylized as TOSHIBA, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. Its diversified products and services include power, industrial and social infrastructure systems, ...

HPS-106

active electronically scanned array An active electronically scanned array (AESA) is a type of phased array antenna, which is a computer-controlled array antenna in which the beam of radio waves can be electronically steered to point in different directions without moving the an ...

(AESA) radar which uses a total of three antennas to provide 240 degree coverage, and Fujitsu HAQ-2 Infrared/Light detection systems for surface detection. The P-1 is also furnished with a

CAE Inc. CAE Inc. (formerly Canadian Aviation Electronics) is a Canadian manufacturer of simulation technologies, modelling technologies and training services to airlines, aircraft manufacturers, healthcare specialists, and defence customers. CAE was fou ...

-built

magnetic anomaly detector A magnetic anomaly detector (MAD) is an instrument used to detect minute variations in the Earth's magnetic field. The term refers specifically to magnetometers used by military forces to detect submarines (a mass of ferromagnetic material c ...

(MAD) embedded into the aircraft's tail, along with deployable sonobuoys, which is used for the detection of submerged submarines. Sophisticated acoustic systems are also used for this purpose. The P-1 has an

artificial intelligence Artificial intelligence (AI) is intelligence—perceiving, synthesizing, and inferring information—demonstrated by machines, as opposed to intelligence displayed by animals and humans. Example tasks in which this is done include speech ...

(AI) system to assist TACCO operations; similar to the

SH-60K SH6 may refer to: * State Highway 6 (New Zealand) * Texas State Highway 6 * Minnesota State Highway 6 See also * List of highways numbered 6 Route 6, or Highway 6, may refer to routes in the following countries: International * Asian Highw ...

, this advanced combat direction system directs the TACCO operator to the optimal flight course to attack a submarine. A large bomb bay housed within the main fuselage, similar in size to that of the Hawker Siddeley Nimrod's, contains the bulk of the aircraft's munitions. The bomb bay is supplemented by a total of eight external

hardpoint A hardpoint is an attachment location on a structural frame designed to transfer force and carry an external or internal structural load, load. The term is usually used to refer to the mounting points (more formally known as a weapon station or ...

s mounted on the wings. Weapons available on the P-1 include

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, ...

es, mines,

depth charge A depth charge is an anti-submarine warfare (ASW) weapon. It is intended to destroy a submarine by being dropped into the water nearby and detonating, subjecting the target to a powerful and destructive hydraulic shock. Most depth charges use h ...

air-to-surface missile An air-to-surface missile (ASM) or air-to-ground missile (AGM) is a missile designed to be launched from military aircraft at targets on land or sea. There are also unpowered guided glide bombs not considered missiles. The two most common pro ...

s (ASMs) (such as the US-built

Harpoon A harpoon is a long spear-like instrument and tool used in fishing, whaling, sealing, and other marine hunting to catch and injure large fish or marine mammals such as seals and whales. It accomplishes this task by impaling the target ani ...

), or bombs. Armaments are managed by a Smith Aerospace-built stores management system, which includes a newly developed Universal Stores Control Unit (USCU) capable of accommodating hundreds of different munitions, including future ones and precision weapons. Multiple

radar warning receiver Radar warning receiver (RWR) systems detect the radio emissions of radar systems. Their primary purpose is to issue a warning when a radar signal that might be a threat is detected, like a fighter aircraft's fire control radar. The warning can ...

s provide all-round awareness of missile threats, which is combined with a defensive countermeasures suite.

Operational history

JMSDF P-1(5506) which takes off from Iwakuni Air Base 20140914

On 31 August 2007, the Japanese Ministry of Defense revealed that they would procure four production airframes. The request in the FY2008 budget was , the unit price for each aircraft at US$141.5 million. In 2013, the ministry ordered two units for ¥44.5 billion. These P-1s were reported to possess increased detection/discrimination capability, flight performance, information processing capability, and strike capabilities as a successor to the existing P-3C fixed-wing patrol aircraft. In June 2007, Kawasaki rolled out the XP-1, a prototype for the P-X program. The rollout had been delayed for three months due to the discovery of defective

rivet A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite to the head is called the ''tail''. On installation, the rivet is placed in a punched ...

s provided by a US supplier which required remedial repairs to be performed. On 28 September 2007, the XP-1 conducted its

maiden flight The maiden flight, also known as first flight, of an aircraft is the first occasion on which it leaves the ground under its own power. The same term is also used for the first launch of rockets. The maiden flight of a new aircraft type is alw ...

from Gifu Air Field,

Kakamigahara, Gifu is a city located in southern Gifu Prefecture in Japan. , the city had an estimated population of 148,225, and a population density of 1700 persons per km2, in 59,736 households. The total area of the city was . Situated in the northern part o ...

, Japan; this flight lasted about one hour and ended successfully. The P-X was redesignated XP-1 at this time. By March 2010, Kawasaki Heavy Industries had delivered four XP-1 maritime patrol test aircraft to Japanese Ministry of Defense; the company also stated its aim for

type certification A type certificate signifies the airworthiness of a particular category of aircraft, according to its manufacturing design (''type design''). It confirms that the aircraft of a new type intended for serial production, is in compliance with applic ...

to be achieved in time for the formal delivery of the first two aircraft by the end of March 2012.Francis, Leithen
"Japan's test programme for maritime patrol and transport aircraft under way."
''Flight International'', 29 March 2010. On 8 August 2011, the

Japanese Ministry of Defense The is an executive department of the Government of Japan responsible for preserving the peace and independence of Japan, and maintaining the country’s national security and the Japan Self-Defense Forces. The ministry is headed by the M ...

announced that two aircraft used for ground testing had developed tears in various parts of the craft, including the fuel tank and central part of the fuselage. In response, modifications to reinforce the affected areas were planned. By October 2012, the problems had been reportedly resolved.Waldron, Greg
"IN FOCUS: China crisis adds urgency to Japanese air force modernisation."
''Flight International'', 8 October 2012. On 26 March 2013, Japan's Maritime Self-Defense Force took delivery of its first pair of P-1s, ahead of a planned two years of test flights. On 14 May 2013, these aircraft were grounded after one developed an unstable combustion condition in some of its engines during mid-flight. P-1 01l

During efforts to sell the aircraft to the UK, a pair of P-1s (one of Air Development Squadron 51Gady, Franz-Stefan
"Japan Seeks To Export its New Sub-Hunting Plane."
''The Diplomat'', 9 July 2015. and one of Air Patrol Squadron 3 were present for the 2015 Royal International Air Tattoo, one aircraft performing a flying display while the other was on static display; this was the first time that any Japanese military aircraft had performed in a European flight display. After its UK appearance, the P-1s proceeded to the

Japan Self-Defense Force Base Djibouti The is a military base operated by the Japan Self-Defense Forces (JSDF) located in Ambouli, Djibouti alongside the Djibouti–Ambouli International Airport. It is the JSDF's first full-scale, long term overseas base. Background Since their es ...

at Ambouli International Airport,

Djibouti Djibouti, ar, جيبوتي ', french: link=no, Djibouti, so, Jabuuti officially the Republic of Djibouti, is a country in the Horn of Africa, bordered by Somalia to the south, Ethiopia to the southwest, Eritrea in the north, and the Red ...

, to continue with operational trials within tropical and desert climates. In November 2016, two P-1s in New Zealand to celebrate the

Royal New Zealand Navy The Royal New Zealand Navy (RNZN; mi, Te Taua Moana o Aotearoa, , Sea Warriors of New Zealand) is the maritime arm of the New Zealand Defence Force. The fleet currently consists of nine ships. The Navy had its origins in the Naval Defence Act ...

's 75th anniversary took part in damage surveys after the 2016 Kaikoura earthquake along with P-3 Orions of the

Royal New Zealand Air Force The Royal New Zealand Air Force (RNZAF) ( mi, Te Tauaarangi o Aotearoa, "The Warriors of the Sky of New Zealand"; previously ', "War Party of the Blue") is the aerial service branch of the New Zealand Defence Force. It was formed from New Zeal ...

and the

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

. In June 2017 a P-1 appeared at the

Paris Air Show The Paris Air Show (french: Salon international de l'aéronautique et de l'espace de Paris-Le Bourget, Salon du Bourget) is a trade fair and air show held in odd years at Paris–Le Bourget Airport in north Paris, France. Organized by the Frenc ...

. In August 2017 Air Patrol Squadron 3 became the first all P-1 operational squadron.厚木航空基地HP トピックス：Ｐ－１への移行完了
Retrieved September 28, 2017 In December 2018, the Japanese Ministry of Defense alleged that a

Gwanggaeto the Great-class destroyer The ''Gwanggaeto the Great''-class destroyers (Hangul: 광개토대왕급 구축함, Hanja: 廣開土大王級驅逐艦), often called KDX-I, are destroyers, but are classified by some as frigates, operated by the Republic of Korea Navy. It was ...

of the South Korean Navy locked its separate target illumination radar onto a P-1 belonging to Air Patrol Squadron 3. The South Korean Navy stated that it had used the radar of an optical camera system and not a fire control system. The

incident Incident may refer to: * A property of a graph in graph theory * ''Incident'' (film), a 1948 film noir * Incident (festival), a cultural festival of The National Institute of Technology in Surathkal, Karnataka, India * Incident (Scientology), a ...

led to a diplomatic row between Japan and South Korea.

Potential operators

France

In 2018 it was reported that Kawasaki was offering the P-1 to France to replace its

Breguet Atlantic Breguet or Bréguet may refer to: * Breguet (watch), watch manufacturer **Abraham-Louis Breguet (1747–1823), Swiss watchmaker **Louis-François-Clement Breguet (1804–1883), French physicist, watchmaker, electrical and telegraph work * Brégue ...

aircraft.

Thailand

In 2016 it was reported that

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...

is considering purchasing the aircraft.

Vietnam

There have been reports that Vietnam is considering buying used P-3 Orions from either the JMSDF or the US Navy or the Kawasaki P-1.

Failed bids

Germany

The P-1 was reportedly offered to Germany as a replacement for its P-3C Orion aircraft in 2018. However, in September 2020, Germany was no longer considering the P-1 due to concerns the aircraft would not be able to achieve military type certification within a required five years time frame.

United Kingdom

In January 2015, it was reported that Tokyo was holding a series of defence talks with the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and ...

to ascertain a possible sale of P-1s to the

Royal Air Force The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) an ...

to replace their recently retired fleet of Hawker Siddeley Nimrod patrol aircraft. The proposal was part of a wider initiative to lower restrictions on Japanese military exports. It was claimed that Britain may consider jointly manufacturing the type, and that the nation could retain rights over related radar and sensor technologies. On November 23, 2015 the UK announced it would buy the

instead of the Kawasaki P-1.

New Zealand

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island coun ...

requested information on the P-1 and Kawasaki C-2 to meet the country's patrol and transport aircraft needs. This request was met with unclassified information in September 2016 and a more detailed proposal including purchase price, manufacturing arrangements, and maintenance complete by mid-2017. This put the P-1 in direct competition with the P-8. On July 9, 2018 it was announced that New Zealand had selected the P-8.

Operators

; :As of March 2022, the JMSDF operated 33 P-1s.Defence of Japan 2022 (Annual White Paper). p.53.
Japan Ministry of Defence *

** Air Development Squadron 51 (2013–present) ** Air Patrol Squadron 3 (2015–present)

Variants

* XP-1: Prototype, later reclassified as UP-1 and assigned to Air Development Squadron 51 * YPX: A cancelled two-engine airliner variant

Specifications (XP-1)

JMSDF P-1(5506) Body rear in Iwakuni Air Base 20140914

3 JMSDF Kawasaki P-1 in flight with Mount Fuji in the background

References

External links

Kawasaki P-1 webpage

Technical Research and Development Institute, Ministry of Defense (Japanese)

Pictures of Kawasaki XP-1
{{JSDF aircraft designations P-1 2000s Japanese patrol aircraft Quadjets Low-wing aircraft Aircraft first flown in 2007