Japan's Defense Ministry has suspended Kawasaki Heavy Industries from bidding on its projects for 2.5 months due to falsified fuel efficiency data on submarine engines built for the Maritime Self-Defense Force from 1988 to 2021. The issue affects engines in 23 of the MSDF's 24 submarines, though officials state it poses no risk to safety or performance.
Japan's Defense Ministry announced on December 27, 2025, a 2.5-month suspension of Kawasaki Heavy Industries (KHI) from bidding on its projects, effective until March 11. The decision stems from the company's falsification of fuel efficiency data for submarine engines supplied to the Maritime Self-Defense Force (MSDF) between 1988 and 2021.
According to the ministry, KHI manipulated test data on assembled engines to meet contractual requirements. All 24 MSDF submarines are powered by KHI engines, with 23 affected—excluding the most recently delivered vessel. Despite the irregularities, the ministry assured that submarine safety and operational performance remain unaffected.
The scandal emerged amid broader scrutiny. In August 2024, similar data falsifications were uncovered in engines for private-sector ships, prompting a ministry inspection of KHI's Kobe plant in Hyogo Prefecture. Earlier, in June 2024, an external panel of lawyers identified potential issues with MSDF engines, which KHI voluntarily reported to the ministry that August. This cooperation led to a reduced suspension period.
As a key defense contractor, KHI's actions have raised questions about procurement integrity in Japan's military buildup. The ministry plans to implement stricter oversight to prevent recurrences.
