Engine corrosion grounds large numbers of Japan s home grown P 1 patrol aircraft

TOKYO – Japan’s P-1 patrol aircraft, a proud symbol of domestic innovation as its first home-grown maritime reconnaissance plane, is “woefully underused” due to engine corrosion and intelligence-gathering equipment failures, the country’s Board of Audit has found.

In a searing 38-page report on June 27, auditors highlighted a litany of defects that could have been prevented during the aircraft’s development. It also blamed delays in securing replacement parts on a lack of proper judgment.

The Defence Ministry said it took the findings seriously.

“Many P-1 aircraft were not in a state where all equipment were functioning properly and could be used for missions without restrictions,” the report said.

“Yet, the P-1 plays an important role in securing Japan’s national interests, with flight patrols over territorial waters, and smooth passage of vessels through its sea lanes.”

The revelation exposes a potential chink in Japan’s maritime surveillance armour as China escalates its activities in the high seas sometimes close to Japan’s outlying islands.

It also underscores the challenges that Japan faces in its efforts to fire up its national defence industry, which has atrophied due to low profitability during a half-century of a weapons export ban that has gradually been eased since 2014.

The auditors launched an ad hoc probe into the P-1 since a “large amount of national funds has been invested in its development”.

The audit also came after the 2023 Defence White Paper cited the P-1 as an example of a military unit that has been crippled by a lack of parts.

Japan spent 1.78 trillion yen (S$15.7 billion) on the research, development, procurement, maintenance and repair of the P-1 from 1991 to 2023, the audit board said.

The P-1 has been globally recognised for its submarine detection prowess, and holds the distinction as the world’s first