On 21 June 2013, a yacht called Eolus struck a sperm whale roughly 1,200 kilometres south-east of Miyagi prefecture and began to sink. Two men took to a life raft: a Japanese newscaster and a blind sailor attempting to cross the Pacific.

A US-2 launched from Iwakuni at 11:39 and turned back. The sea was too rough even for this aircraft. A second launched at 15:08, landed on the open ocean, and had both men aboard by 18:14.

There is no helicopter with that reach and no other fixed-wing aircraft that can land out there to use it. The ShinMaywa US-2 exists to occupy that gap, and it is the only aircraft in the world currently doing so.

The problem it solves

Ocean rescue has an ugly geometry. A helicopter can hover over a life raft but cannot reach far offshore. A long-range aircraft can reach the raft in hours but can only circle above it and drop equipment.

Japan has a great deal of ocean and a search-and-rescue region that extends well past helicopter range, so the JMSDF kept alive a capability almost everyone else abandoned: an aeroplane that flies out at 300 knots and then lands on the sea.

The difficulty is that these are contradictory requirements. Landing on water in a seaway demands the slowest possible touchdown speed, because waves do not flatten out for you. Getting there quickly demands a wing built for cruise. The US-2’s answer is to cheat, using an entire additional engine.

The fifth engine

Four Rolls-Royce AE 2100J turboprops provide thrust. A fifth engine, an LHTEC CTS800 turboshaft, provides no thrust at all.

It drives a compressor whose only job is to blow high-pressure air over the upper surfaces of the wing and tail. This is boundary layer control: energising the airflow so it stays attached over a flap deflected to sixty degrees, a setting at which an unblown wing would simply have stalled.

The payoff is a controllable speed of roughly 50 knots. For scale, that is slower than many light aircraft approach, in an airframe with a maximum weight around 47 tonnes.

The JMSDF’s own channel filmed a water take-off from on board, above.

That is also why the take-off numbers look implausible. From water at 43 tonnes the US-2 is airborne in 280 metres, a figure Japanese press timed at about five seconds. From land it needs 490 metres at maximum weight.

Landing on a wave

ShinMaywa advertises the ability to land in three-metre seas, and also describes the aircraft as able to land on waves a third of its own height. Both are marketing formulations of the same certified capability.

Operationally it is messier. The 2013 rescue was flown in a reported four-metre sea, after a first aircraft had already turned back. Crews do not use wave height alone; the go or no-go decision runs on a combined index of wave height and wavelength scored out of a hundred, because a long swell and a short chop of the same height are entirely different propositions.

A veteran squadron pilot described the technique to Jiji Press as slowing right to the limit and dropping the aircraft hard onto a wave that is just about to break, and said that after enough years the sea has zones that appear to glow where a landing is possible.

What changed from the US-1A

The US-2 looks like its predecessor and is a substantially different aeroplane. The single most consequential change is not aerodynamic at all: the forward and centre fuselage were rebuilt as a pressurised section.

The earlier PS-1 and US-1A had no cabin pressurisation whatsoever, which meant cruising at around 10,000 feet and flying through weather rather than over it, on missions that could last many hours. The US-2 cruises at 20,000 feet. For a crew that must arrive fit to dive into a rough sea, that is a bigger gain than any speed figure.

It also brought triplex fly-by-wire, retaining one hydraulic channel as backup, and a glass cockpit with eight displays.

A very small fleet

Here the story turns awkward. Ten airframes have been funded, two prototypes and eight production aircraft. One was lost in 2015 off Cape Ashizuri during a three-engine water take-off, when an engine and a float were torn away and the aircraft sank in 300 metres of water. All nineteen aboard were rescued by a passing tanker. The investigation found excessive control inputs compounded by the absence of a defined three-engine take-off procedure.

The first prototype was retired in August 2024. As of March 2025, Japan’s defence white paper recorded six on strength, with the ninth airframe in build.

Six aircraft, for a search-and-rescue region covering a substantial fraction of the western Pacific.

Japan’s Joint Staff released the footage above of a real casualty evacuation flown in April 2025.

Why nobody else bought one

The US-2 should be an obvious export. It has been offered repeatedly and has never sold.

India came closest. A requirement for around twelve amphibians was discussed from the early 2010s, negotiations opened in 2011, and ShinMaywa cut its offer from roughly $133 million to about $113 million per aircraft in 2016. A signature expected during a Tokyo visit that November was deferred, an industrial memorandum with Mahindra followed in 2018, and the whole thing was shelved by 2021 over price. In January 2026 India issued a request for information to wet-lease four amphibious aircraft for four years, which reopens the door without committing to buy anything.

Indonesia was offered three aircraft at about $100 million each in 2016 and chose the Canadian Viking CL-515 instead. Greece evaluated the type after the 2018 Attica fires and bought DHC-515s.

The obstacle is arithmetic. Japan itself skipped procurement in two consecutive years as the quoted price climbed, and Reuters reported in 2023 that a plan to buy two aircraft was scrapped after the price per aircraft nearly doubled to 30 billion yen. ShinMaywa declines to publish a price at all, telling Naval News that it varies widely with requirements.

A niche capability built in tiny numbers is expensive per unit, which shrinks the customer base, which keeps the numbers tiny. Amphibians competing for the firefighting market face a rival built in larger numbers for a broader mission, and the US-2 is not optimised for dropping water.

The people who fly it

The 71st Air Rescue Squadron holds an alert posture measured in tens of minutes: airborne within an hour, or about thirty if the main engines are ready to start. It flies somewhere in the region of thirty to forty search-and-rescue and disaster-relief sorties a year, and marked its fiftieth anniversary in July 2026.

The aircraft has begun appearing further afield. American special operations personnel examined one at Andersen Air Force Base in 2022 during market research into amphibious capability, and in April 2026 a 71st Squadron aircraft landed in the West Philippine Sea for a casualty evacuation drill with a US Navy landing ship, the type’s Philippine debut.

Whether that interest ever becomes a contract is a different question. What is not in doubt is the gap the aircraft fills. Somewhere beyond helicopter range there is a life raft, and the US-2 is the only aeroplane in service that can go and get it.

Sources: ShinMaywa Industries technical and capability pages; JMSDF and Japanese Ministry of Defense equipment pages and press releases; Japan Defense White Paper FY2025; Naval News (Peter Ong, 2022); The Aviationist; Jiji Press; Mainichi Shimbun; Reuters; Sasakawa Peace Foundation.