Is it a ship? Is it a plane? Viral images spark buzz over China reviving Soviet-era 'Sea Monster' tech

It looks like something straight out of a Cold War science fiction novel: a hulking sea-skimming machine blending the body of a ship with the wings of an aircraft. However, But China’s latest experimental vehicle, nicknamed the "Bohai Sea Monster", is no fantasy. Newly surfaced images of this mysterious craft have triggered intense speculation among defence analysts, suggesting that Beijing is reviving a decades-old Soviet concept with fresh ambition.

Known as a wing-in-ground effect (WIG) craft, or more specifically an ekranoplan, this hybrid platform could reshape the dynamics of regional military logistics, amphibious assaults, and stealth operations in the South China Sea and beyond.

What makes ‘Bohai Sea Monster’ unique?

The newly released images of what’s being called the Bohai Sea Monster show a sleek, gray aircraft with a flying-boat hull, twin tail fins, and four jet engines mounted on its wings. It appears far more advanced than any similar craft seen since the Cold War.

Drawing comparisons to the Soviet-era “Caspian Sea Monster,” this type of aircraft, known as a ground effect vehicle, flies just a few meters above water, reducing fuel use, drag, and radar detection. Analysts believe China may use it for military logistics, such as quickly transporting troops, resupplying islands, or landing vehicles on beaches, thanks to its speed, stealth, and amphibious capabilities.

Pros and cons of Ekranoplans

Ekranoplans offer a mix of speed and efficiency, flying faster than ships while using less fuel than traditional aircraft at low altitudes. Their low radar profile also makes them harder to detect, and they can operate in challenging weather. This makes them well-suited for “gray-zone” missions where stealth and quick response are key.

However, they come with major limitations: they have limited manoeuvrability and rely on relatively calm seas (around Sea State 4) to function properly. If conditions worsen during a mission, their performance and safety can be significantly compromised.

Implications for Asia-Pacific

The Bohai Sea Monster could have major strategic implications in the Asia-Pacific. With the ability to reach hotspots like Taiwan or the South China Sea in about four hours, it could support China’s plans for island seizures or blockades. Its low-flying, radar-evading design makes it ideal for quietly moving troops or supplies into contested areas, potentially creating stealth supply chains. It also fills a gap between warships and aircraft carriers, offering a fast, high-capacity option for coastal warfare that could give China an edge in littoral conflicts.

US developing its own ambition: Liberty Lifter

The DARPA-backed Liberty Lifter, a comparable ground-effect vehicle, was under development until June 2025. The US has proven the technology, demonstrated logistics potential, but chose to halt full build-out, shifting toward leveraging tech rather than fielding prototypes.

It is designed to transport heavy loads (up to C‑17-class payloads) at ~10,000 ft altitude and helicopter-like speeds (~180 kt), and operate sea-state compatible, water-capable, runway-free, for flexible military logistics.

Why this matters now?

China’s Bohai Sea Monster is the most advanced ekranoplan seen in decades, signalling a return to Cold War-style naval innovation. Its appearance suggests China may now have a stealthy, fast-moving tool for high-risk military missions. It also reflects a broader tech race, with other nations like the US exploring similar capabilities.

As tensions rise in global hotspots, these low-flying, sea-skimming craft could reshape how countries approach amphibious warfare and maritime logistics, not just in Asia, but around the world.