Shinmaywa continues its slow production of the US-2 amphibian, while a long hoped-for India export deal remains on the horizon.

The company has delivered six examples to the Japan Maritime Self Defense Force, although one was lost in a 2015 accident at sea. Two more example are under construction in Kobe.

Ultimately, Tokyo plans to operate seven of the type. The first aircraft will be retired, but a ninth aircraft will replace it, likely in the mid-2020s. With seven aircraft, four can be operational and three in maintenance.

Masayuki Tanaka, manager of defence programmes at the airframer, says the slow rate of production at the company’s Kobe plant presents challenges both for labor and the supply chain.

When not working on the US-2, company technicians are deployed to other projects in the company’s aerospace business. Another challenge is Japan’s aging population, which can see engineers with programme familiarity retire.

“This is a fundamental issue,” he says, noting that the company also works to hire fresh graduates.

The future of the programme, however, likely lies beyond Japan. For several years, New Delhi and Tokyo have had government-to-government discussions about a potential deal for nine aircraft. Should this move forward, Shinmaywa would partner with Mahindra Defence Systems for local production.

Tanaka calls the India deal “very important” for the US-2’s future.

Powered by four Rolls-Royce AE2100J turboprops, the US-2 has a maximum range of 2,540nm (4,700km) and can take off and land in 3m (10ft) swells.

The aircraft has a unique boundary layer control (BLC) system, which uses compressed air from the slit of the flaps to prevent air flow separation and increase lift. This allows the aircraft to land in high sea states that would inaccessible for other amphibious aircraft.