ShinMaywa is working on the 10th US-2 amphibian for the Japan Maritime Self-Defense Force — and has yet to receive a commitment for an 11th. The company's ability to keep building the type now hinges on Tokyo placing further orders.

According to a company report, ShinMaywa's priority is completing aircraft 10 for the JMSDF and then securing additional orders that would preserve the industrial capability to produce more of the amphibians. Tokyo has announced no commitment for a follow-on aircraft.

Beyond new-build orders, ShinMaywa also wants longer-term maintenance contracts covering the JMSDF's US-2 fleet. Such deals would stabilise revenue from the programme. The company aims to hold US-2-related revenue at Y8-10 billion ($51-63 million) annually.

The production rate underscores the fragility of the industrial base ShinMaywa is trying to protect. The company has built the US-2 slowly and in small numbers over the programme's life, and a gap between aircraft 10 and a potential aircraft 11 would put skills and supply chains at risk — the core concern behind the push for follow-on orders.

The US-2 is the world's second-largest amphibian flying today, behind only the AVIC AG600. Four Rolls-Royce AE2100J turboprops power the aircraft, which has a maximum range of 2,540nm (4,700km) and can take off and land in 3m (10ft) swells.

Its distinguishing technology is a boundary-layer-control (BLC) system. Compressed air discharged through slots in the flaps prevents airflow separation and increases lift, allowing the aircraft to operate in high sea states that other amphibious aircraft cannot access. The JMSDF flies the type in the long-range search-and-rescue mission.

The company report also highlights broader aerospace activity, including development of an uncrewed aircraft. ShinMaywa has previously disclosed testing of an unmanned amphibian designated XU-M II for oceanic research missions. The test article is one-fifth the scale of a proposed unmanned amphibian — a programme that remains at the demonstrator stage rather than a certified product.

ShinMaywa's commercial aerospace work provides revenue independent of the US-2 programme. The company produces wing spars for the Boeing 787, wing-body fairings for the 777 and 777X, and components for the Bombardier Global 7500 business jet.

For now, the central question is budgetary rather than technical. The US-2's capability set is proven and in service; what is missing is a funded requirement for aircraft 11. Until Tokyo signals a commitment, ShinMaywa's amphibian industrial base — and the Y8-10 billion annual revenue target attached to it — rests on maintenance contracts and the pace of decisions in Japan's defence budget cycle.