VESSEL REVIEW | Soya – Japan Coast Guard's new large patrol vessel boasts icebreaking capability

The Japan Coast Guard recently placed a new large patrol vessel into service.

Soya (そうや) was built by Japan Marine United (JMU) as a replacement for a slightly smaller and similarly named vessel that had been operated by the coast guard since 1978.

The newer Soya has an LOA of 92.4 metres (303 feet), a beam of 16.4 metres (53.8 feet), a gross tonnage of 4,200, and icebreaking capability. Her dimensions make her the largest icebreaking patrol vessel currently in active service with the Japan Coast Guard.

Combining fast patrol capability with sustained power for ice navigation

JMU said its technical research institute’s ice sea testing tank was used to conduct repeated tests simulating real sea conditions. This allowed for the adoption of a hull design that could achieve high operational efficiency, whether breaking through ice or sailing at high transit speeds in open water.

The builder added that the newer Soya is equipped with a remote-controlled water cannon, a feature that had not been available on her predecessor vessel. She also incorporates an optimised anti-roll system and boasts improved turning performance.

Built for long-term deployment in northern Japanese waters

Soya’s large size also permits the incorporation of a flight deck for use by a helicopter for utility, light transport, and search and rescue.

Like the earlier Soya, the 2025-built vessel will be operated primarily in the ice-covered waters just off northern Japan, providing patrol coverage and emergency response assistance for commercial ships and fishing vessels.

Her deployment will also enable Japan to maintain a year-round presence in the Sea of Okhotsk and along the maritime approaches around Hokkaido.