ShinMaywa Industries has begun assembling the first modernised US-1A Kai search and rescue amphibian for the Japanese Maritime Self-Defense Force (JMSDF). It is on track to fly the aircraft in August next year.

Mitsubishi Heavy Industries (MHI) recently delivered an upgraded boundary layer control system for the initial aircraft, which uses an LHTEC CTS800 turboshaft-driven compressor to blow air over the upper surfaces of the wing, flaps, ailerons and horizontal stabiliser.

This enables the aircraft to land at a lower air speed in rough seas.

The original version of the US-1A entered service in 1975 and is equipped with a boundary layer control system based around the General Electric T58, according to project-team section manager Kanji Ishimaru.

Two US-1A Kai airframes have been produced for static and fatigue testing at ShinMaywa's factory at Kobe near Osaka. Parts fabrication for the second flyable aircraft has also started, according to Ishimaru.

The Japan Defence Agency is expected to place an initial order for seven of the new four-engined flying boats for service entry in June 2006 to replace the existing fleet of US-1As. Up to 14 aircraft are required.

Among changes introduced on the US-1A Kai is the switch to Rolls-Royce AE2100J turboprops with six-bladed Dowty R414 propellers, which replace the General Electric T64-10J engines.

It also has a Kawasaki-designed fly-by-wire flight control system, glass cockpit, pressurised upper hull, modified wing with integral fuel-tanks and Honeywell RE220 auxiliary power unit.

Source: Flight International