China's newest aircraft carrier, the Fujian, may be the first in the world to carry an active anti-torpedo torpedo (ATT) defense system, according to recent reports. The development signals that Beijing's push for blue-water naval power still faces its most dangerous challenge from beneath the waves.
The Fujian, China's third carrier and its first domestically designed vessel, features a six-tube, 324-millimeter lightweight torpedo launcher. This replaces the 12-tube depth charge launchers seen on its predecessors, the Liaoning and Shandong. The system appears designed as a direct response to the threat posed by US Navy Seawolf-class and next-generation SSN(X) attack submarines, whose heavy wire-guided torpedoes can inflict more devastating damage on large warships than anti-ship missiles.
How the Anti-Torpedo System Works
The ATT interceptor uses a broadband sonar array to distinguish real targets from decoys. A high-torque permanent-magnet pump-jet thruster can accelerate the weapon to 50–60 knots within three seconds, allowing it to track highly maneuverable torpedoes. To guarantee single-hit destruction, the ATT deploys directional shaped charges and overpressure shockwaves. Potential supercavitation upgrades could enable defensive velocities of up to 200 knots to counter close-range underwater threats.
China's development of an active ATT system reflects an effort to compensate for persistent People's Liberation Army Navy (PLAN) anti-submarine warfare (ASW) deficiencies by strengthening the carrier strike group's organic point-defense layer against advanced US undersea threats.
Persistent ASW Weaknesses
China's current carrier doctrine may underscore its deficiencies in ASW capabilities. Steve Balestrieri, writing for 1945 in February 2026, notes that China's carriers were designed to operate relatively close to its shores, under cover of land-based missile networks and aircraft, rather than having comprehensive onboard defenses. This approach stands in contrast to US carriers, which serve as "roaming nerve centers" for a wider network.
Consequently, while China relies on long-range land-based missiles to threaten enemy carriers at range, its own carriers remain vulnerable to direct attack. US Virginia-class submarines, armed with the Mk48 heavyweight torpedo and Maritime Strike Tomahawk (MST) missiles, can threaten Chinese carriers.
Deficiencies in PLAN ASW capabilities, particularly airborne ASW, compound the vulnerability. Eli Tirk and Daniel Salisbury, in a May 2024 report for the China Maritime Studies Institute (CMSI), note that China's airborne ASW force has historically been constrained by a shortage of fixed-wing maritime patrol aircraft and has struggled with lagging operator proficiency and training deficiencies. They add that PLAN airborne ASW training has traditionally lacked realism due to administrative barriers that prevent training in diverse environments. While the PLAN has aggressively fielded newer platforms, qualitative advancements in sensor data processing and weapons remain constrained, leaving the force's capability to execute complex joint-arms ASW operations largely aspirational.
Andrew Erickson, in a March 2026 testimony to the US-China Economic and Security Review Commission (USCC), highlights wider systemic vulnerabilities. He states that a critical impediment is China's deficient meteorology and oceanography capabilities, which lag behind the US Navy and leave the PLAN with a comparative ignorance of the ocean battlespace. A lack of deployed sensors, limited patrol aviation, and inadequate logistics infrastructure severely constrains out-of-area ASW operations. The PLAN also faces major operational weaknesses in mine countermeasures (MCM) and real-time, time-sensitive data fusion due to complex intra-service coordination hurdles.
Submarine Stealth Gap
While the PLAN has overtaken the US Navy in fleet size, the latter maintains a significant advantage in submarine stealth. In a report this month for the Korea Institute of Maritime Strategy (KIMS), Erickson points out that acoustic signatures remain a persistent Achilles heel for Chinese submarines. Second-generation Type 093 nuclear attack submarine (SSN) and Type 094 nuclear ballistic missile submarine (SSBN) hulls are significantly louder at high speeds than their world-class US counterparts due to a lack of advanced pump jet propulsion and natural reactor circulation.
Erickson notes that while China's initial nuclear platforms suffered from extreme noise deficiencies, the PLAN has worked aggressively to close this acoustic gap. Through lower-vibration machinery and reverse-engineered Russian pneumatic isolation mounts, China has achieved noteworthy breakthroughs. Its forthcoming third-generation Type 095 SSN and Type 096 SSBN are projected to finally approach Russian Improved Akula-class stealth standards.
US submarines are actively operating along China's periphery. The South China Sea Strategic Situation Probing Initiative (SCSPI), a Chinese think tank, released a report in June 2026 stating that in 2025 the US deployed at least 11 nuclear-powered attack submarines (SSNs) and one nuclear-powered guided-missile submarine (SSGN), the USS Ohio, in the South China Sea. The SCSPI report adds that the US Navy relied on auxiliary submarine tenders, including the USS Emory S. Land and USS Frank Cable, to provide critical logistics support and conduct multinational port visits to sustain these forward-deployed undersea forces.
As China builds its fourth aircraft carrier, likely nuclear-powered, it may eventually be able to sustain prolonged operations far from home. But for now, the Fujian's anti-torpedo system is a clear admission that the underwater threat remains the most dangerous obstacle to Beijing's maritime ambitions. For more on China's naval strategy, see our analysis of China's Submarine Missile Test: Routine Drill or Pacific Provocation? and Power Prevails but Law Still Matters in the South China Sea.
