Razor-sharp bow saves fuel on new Mitsubishi-built Japanese ferry

Since going into operation in September, the 14,300-gt ropax vessel Hamanasu has showcased the latest technology developed in Japan to revive the nation’s sagging shipbuilding industry to compete with global leaders China and South Korea.

Built for Shin-Nihonkai Group, the 200 m ropax ferry plies a 480 nm, roughly 21-hour coastal route between Otaru and Maizuru at a service speed of over 28 knots, carrying up to 286 passengers and 150 trucks and 30 cars.

Critical for the SHK Line-owned ferry company is that the vessel’s fuel consumption is 5% lower than its larger 22-year-old predecessor, according to Mitsubishi Shipbuilding, part of Mitsubishi Heavy Industries. Last year, Mitsubishi Shipbuilding delivered sister vessel Keyaki.

The gains are achieved through three main technologies. One is a first-of-a-kind knife-like, nearly vertical Katana bow, named for a Japanese sword, which is designed to slice through waves with minimum disruption. Two is a buttock stern and ducktail that smooth out water flow as it exits the ship. And three is a self-levelling roll-damping tank that keeps the ferry on its designed lines in tandem with stabilisers.

The technology has been deployed successfully for nearly a year on a sister ship, Keyaki, and other Japanese shipbuilders are following both ferries’ performance closely. The two ships are driven by four Mitsubishi 8,540-kW main engines.

The advances aren’t confined to the propulsion system; an experimental installation of lightweight perovskite solar cells is being tested on an exposed deck, and Starlink is available in the cabins.

Osaka-based, 55-year-old Shin Nihonkai’s new ferries are among the first beneficiaries of Japan’s maritime revival. With an 11-strong fleet of high-speed and conventional ferries, Shin-Nihonkai is a key member of the consortium involved in Japan’s US$82M, five-year shipbuilding revival plan.

Formed in 2025, the consortium consists of 10 shipbuilders, including Mitsubishi, Tsuneishi, MTI, NYK, Japan Marine United, Mitsui, and several research institutes such as the Japan Agency for Marine-Earth Science and Technology, National Maritime Research Institute, and Kyoto University. The official goal is to enhance the competitiveness and digital transformation of the maritime industry through the creation of “next-generation, high-performance vessels”, which includes Keyaki and Hamanasu.

State-sponsored collaboration has been coming up with real-world results. Oshima Shipbuilding has developed a system that blows a continuous layer of bubbles known as “micro-air” under the flat bottom of the hull that reduces friction. Oshima estimates energy savings of up to 8%.

Other ropax ferries are being built with aerodynamic, low-profile upper structures that are designed to reduce headwind resistance by 10-15%, particularly important in the typhoon season.

More ferries are adopting Japan-invented propulsion technologies such as the boss cap fins and contra-rotating propellers that harness the otherwise wasted underwater vortex behind the hub. The angled fins recapture the energy and convert it into straight-line speed for efficiency gains estimated at between 3 and 5%. Several ferries have recently installed contra-rotating propellers.

Sea trials are being conducted to develop dual-fuel hydrogen ferries in the wake of the 2021-launched, 80-passenger Hydrobingo. These vessels run on a mix of hydrogen and standard marine fuels. One of the most recent is the 33-m long, 100-passenger capacity Hanaria, Mitsui OSK Line’s trimaran that is fuelled by portable hydrogen tanks, lithium-ion batteries or a biodiesel generator.

And in late 2025, the 500-passenger ropax Olympia Dream Seto was certified for autonomous operation under one of the Nippon Foundation’s projects that aim to integrate AI into the propulsion system. The approval followed demonstration sailings after a complex renovation involving Mitsubishi Shipbuilding, Mitsui E&S, and Japan Marine Science in close collaboration. The main concern throughout was collision avoidance in the crowded sea routes of the Seto Inland Sea and berthing alongside narrow wharves.