For the first time since the Second World War, the Japanese aerospace industry has demonstrated a new defense air program overseas in an attempt to interest potential export customers. In the post-war era, following millions of deaths in occupied Asia, it is understandable why the new peacetime Japanese administration had to incorporate legislation that made it illegal to export military weapons (including aircraft), or to participate in overseas military operations. This allowed the Japanese aviation industry to develop and build military aircraft, often in cooperation with Western partners, but restricted them to home defense.
Now, following increased concerns over the expansion of Chinese and Russian forces in the Pacific region, with rising tension over disputed sovereignty over small islands, the Japanese government is introducing new legislation to allow its military forces to play a more active role in supporting wider military cooperation with regional allies as well as the U.S.
The surprise appearance of Japan’s latest military aircraft, the Kawasaki P-1, at the recent RIAT air show in the U.K., the year’s largest international gathering of military aircraft and senior air chiefs, marked the first public expression of this new, more outward-looking defense initiative. It was also the first time that this new four-jet Maritime Patrol Aircraft (MPA) had been put on display outside Japan, and provided an interesting comparison with Boeing’s new P-8 Poseidon MPA, which also took part in the event.
The P-1 was designed to provide a jet-powered long-endurance/long-range patrol aircraft that could cover the large number of scattered and remote Pacific islands that are under Japanese national jurisdiction as well as the main Japanese coastal waters that see very large numbers of commercial shipping.
These waters are seeing more submarine movements than ever before, and because of the large distances involved in carrying out maritime patrols, the Japanese Maritime Self-Defense Force (JMSDF) decided that it needed a jet-powered replacement for its fleet of Kawasaki/Lockheed P-3C Orion MPA aircraft. These P-3s were built under license in Japan and have served the JMSDF well for many decades, but the turboprop design is now dated and although this format provides good low-level performance in seeking and tracking surface and sub-surface vessels, and in the search-and-rescue role, the transit times are long.
The U.S. Navy later reached a similar conclusion regarding its own P-3C replacement, which resulted in the development of the Boeing 737-based P-8 Poseidon MPA. But before the P-8 was selected by the USN, Japan embarked on a lengthy and very expensive “home-grown” jet MPA program, which resulted in the P-1.
This was a very ambitious project as it comprised an all-new platform aircraft, with all-new avionics, mission, and weapons systems, and an all-new turbofan engine. The total requirement was for up to 70 aircraft for the JMSDF and during development this cost has not been shared with any overseas industrial partners, and until now, it was not considered likely that it would ever be offered on the international defense market. So the appearance of the P-1 at RIAT in July represents a major turning point in over 60 years of post-war Japanese aerospace regeneration.
The P-1 is built by Kawasaki, which also has overall design responsibility for the onboard electronics, including the integrated mission system. The new turbofan engine is designated the IHI F-7-10 and is more compact, with lower thrust than the CFM-56 aboard the P-8 Poseidon. But unlike the twin engine configuration on that airplane, the P-1 has four turbofans. This gives very good high-speed transit time and extra safety on long endurance missions but is thought to be more costly to operate and maintain as a one-off design than the P-8, which has many standard 737 features and is supported by a global support network. It is claimed that the P-1’s maximum range is around 5000 mi.
The two aircraft brought to Europe were not fitted with in flight refueling probes and with what appeared to be a satellite communications dome just behind the cockpit, there did not appear to be provision or space for a boom refueling receptacle on the upper front fuselage. The first flight of the prototype P-1 took place at Gifu Air Base in Japan in September 2007 and the first production-standard P-1s from an initial batch of 20 entered Japanese military service in 2013.
Very little has been revealed about this aircraft and until now, few outside Japan have seen it. There are many aerials distributed about the airframe, indicating a comprehensive communications fit and suggesting an advanced electronic warfare capability, perhaps extending into communications intelligence.
A magnetic anomaly detector (MAD) “stinger” in the tail highlights its anti-submarine capability, along with multiple sonar launch tubes beneath the rear fuselage. There are also multiple radar-warning sensors giving all-round situational awareness for self-defense, no doubt with missile-jamming countermeasures capability. A Harpoon missile can be carried in the small forward weapons bay, or torpedoes, but there do not appear to be weapons pylons below the wings.
Toshiba has developed an advanced HPS-106 active electronically scanned array air-to-sea search radar for the surface surveillance and tracking mission. Although no details were announced at RIAT, the company stated that the P-1 is the first operational aircraft to be fitted with a fly-by-light flight control system.
In an age where there is little variety in the way of all-new aircraft designs, and most recent military surveillance or special mission aircraft have been produced by adapting existing commercial or military transport platforms, the appearance of the P-1, which is conventional and has been optimized around its anti-submarine/MPA role, makes a welcome appearance and it will be interesting to see if more detail regarding its performance and systems will be revealed over the coming months and years—especially if Kawasaki is intending to compete with the Boeing P-8 in world markets.