China’s newly revealed sailless submarine may be designed not only to evade detection but also to threaten the undersea infrastructure underpinning Indo-Pacific military and economic power.
This month, Naval News reported that China has covertly launched a highly advanced, “sailless” submarine class from the Jiangnan Shipyard in Shanghai, marking a major technological leap in its rapid naval expansion.
Discovered via satellite imagery, the approximately 120-meter-long vessel features a distinctive streamlined hull, X-form rudders, and a radically minimized superstructure designed to reduce underwater drag.
China may have launched two vessels at the Huludao shipyard in the Bohai Sea, a facility specializing in nuclear-powered submarine construction. The parallel rollouts underscore how China is outpacing Western navies, having produced roughly 15 to 20 submarines across eight distinct classes over the past five years.
While the People’s Liberation Army Navy (PLAN) has maintained strict official silence, the submarine’s massive dimensions suggest traditional nuclear propulsion rather than standard air-independent power.
The sudden emergence of this class complicates intelligence assessments and disrupts initial assumptions about China’s next-generation Type-095 attack submarine program.
Noting the pros and cons of sailless submarine design, Joseph Trevithick, in an article this month for The War Zone (TWZ), mentions that omitting a large structure from the top of the hull enhances streamlining, boosting speed, maneuverability and quietness while submerged—making the submarine harder to detect, even at high speeds.
Trevithick says that a sailless design is especially advantageous when rapidly approaching distant threats, noting that while traditional sails house periscopes, sensors, antennas, and snorkels, removing them frees space for other equipment like countermeasure launchers and storage. He also notes that a sailless design may focus on seabed operations, where mast deployment is less critical, or on optimizing transit speed during blue-water missions.
Building on Trevithick’s perspectives, a sailless submarine may offer enhanced stealth for penetrating US and allied anti-submarine defenses in the First Island Chain. Such a capability would be particularly valuable against the US “Fish Hook” underwater sensor network stretching across Japan, Taiwan, the Philippines and Indonesia.
Noting the stealth limitations of Chinese submarines, Ryan Martinson, in a June 2025 article for the Center for International Maritime Security (CIMSEC), cites Chinese military journal articles stating that the PLAN cannot guarantee submarine stealth due to a pervasive US undersea surveillance network.
According to Chinese journals cited by Martinson, China’s Near Seas – the First Island Chain, has become highly transparent. He notes that the US military uses a comprehensive network of satellites, fixed seabed sonar arrays, and maritime patrol aircraft, creating an “extremely high” probability that Chinese submarines are detected immediately upon leaving port, thereby severely undermining their operational utility and compromising China’s sea-based nuclear deterrent.
While China could attempt a mass breakout using nuclear submarines – having 32 such vessels in January 2026 – such an attempt may create predictable “fatal funnels” that concentrate US and allied anti-submarine efforts at critical chokepoints such as the Miyako Strait and the Bashi Channel.
Regarding submarine fleet numbers, while the US has an all-nuclear fleet of 71 submarines in January 2026, James Eanell notes in a May 2026 Proceedings article that China may have up to 70 submarines by 2027 and 80 by 2035, with half of them nuclear-powered.
However, Roy Wood mentions in a February 2026 Proceedings article that the US submarine fleet will hit a low point of 46 units in 2030 as Los Angeles–class retirements outpace Virginia–class deliveries. Wood says the US fleet’s trajectory projects a recovery to the low-50s by 2040, but it will not achieve its long-term objective of 66 hulls until the mid-2050s.
Should China’s nuclear submarines penetrate US and allied anti-submarine defenses in the First Island Chain, they could be employed as a forward screen to provide intelligence, surveillance, and reconnaissance (ISR) of US and allied vessels, escort China’s carrier strike groups headed toward the open Pacific or be directed to attack high-value US targets, such as carriers.
China’s new sailless submarine could be optimized for prolonged seabed operations, with its apparent nuclear propulsion and large size offering the endurance required for extended missions on the ocean floor.
Such characteristics align with a growing focus among major powers on undersea infrastructure competition, including the ability to monitor, tap or sever critical communications cables.
Highlighting the vulnerability of undersea internet cables, Niklas Swanstrom mentions in a January 2025 policy brief for the Institute for Security and Development Policy (ISDP) that they carry up to 99% of international internet traffic, making them critical yet highly vulnerable infrastructure. Swanstrom notes that these cables, mostly in international waters, face physical threats, including state-sponsored sabotage.
Notably, the US and Russia operate special mission nuclear-powered submarines, such as the USS Jimmy Carter and Losharik, both allegedly capable of tapping or severing undersea internet cables. If optimized for seabed warfare, the submarine would place China among a small group of powers fielding platforms capable of conducting undersea infrastructure operations.
If so, China’s new sailless submarine poses a threat to Taiwan’s undersea internet cable infrastructure. Jason Hsu mentions in a March 2026 testimony before the US-China Economic and Security Review Commission (USCC) that Taiwan’s heavy reliance on just 24 undersea fiber-optic cables that land at eight highly concentrated landing stations creates severe geographic chokepoints vulnerable to targeted Chinese gray-zone sabotage.
Hsu details how Chinese civilian vessels systematically sever these links using anchor-dragging techniques to evade military attribution. He also warns that Chinese repair ships could physically tap the cables to intercept allied military data. He points out that cutting three major cable clusters near the Bashi Channel could immediately eliminate 99% of Taiwan’s digital bandwidth.
He warns that such a digital blockade would paralyze global semiconductor supply chains, disrupt international financial markets, freeze government operations, and sever vital allied military coordination during the opening hours of a cross-strait conflict.
Beyond Taiwan, the undersea internet cable infrastructure connecting East Asia to the US may be similarly vulnerable. In a September 2025 policy paper for the Center for Irregular Warfare and Armed Groups (CIWAG), Jahara Matisek and other writers note that the vulnerability of trans-Pacific undersea infrastructure centers on highly exposed geographic chokepoints.
Matisek and others specifically point out that Hawaii, Guam, and the US West Coast serve as the critical landing nodes for all data and energy cables connecting the US to East Asia.
They stress that this extreme concentration poses severe strategic risks, warning that disruptions at these nodes during a crisis would directly paralyze commercial networks, degrade operational tempo, and sever critical military command-and-control capabilities — thereby specifically undermining the US Indo-Pacific Command’s (INDOPACOM) ability to maintain strategic communication lines.
By combining enhanced stealth with potential seabed warfare capabilities, China’s new sailless submarine may shift undersea competition from penetrating the First Island Chain to contesting the digital infrastructure that underpins US power in the Pacific.
