China is developing systems to hunt American submarines from the air

The Chinese Navy considers Anti-Submarine Warfare, or ASW, essential to the success of any amphibious operation and intends to use its aircraft to protect its fleet from an attack by US or Japanese submarines.

According to a report by the US Naval War College's China Institute for Maritime Studies, China's Navy considers fixed-wing and vertical-lift ASW capabilities to be a crucial component of any amphibious contingency, whether it's the seizure of an island or reef, or the successful implementation of a “Joint Island Landing Campaign against Taiwan”.

“ASW capabilities would be crucial for safeguarding high-value surface assets such as aircraft carriers or an amphibious landing party, protecting them when they are in port embarking forces, clearing the operational area of enemy submarines and escorting these assets on their way to staging areas and operational areas,” consider the authors of the study, analysts Eli Tirk and Daniel Salisbury.

Chinese aerial submarine hunters are also tasked with protecting Chinese ballistic missile submarines as they sail to their patrol and launch sites.

“The Chinese Navy clearly sees fixed-wing ASW as an important factor in nuclear deterrence at sea,” the report points out.

The Chinese Navy's current fixed-wing anti-submarine aircraft is the Shaanxi KQ-200, a four-engine turboprop aircraft with a range of around 4,800 km, which is the Chinese equivalent of the US Navy's P-8 Poseidon. According to Business Insider, the Chinese Navy has around 20 KQ-200s.

Like the US Navy, China's submarine force tends to be secretive. But by examining open source information, Tirk and Salisbury were able to identify China's efforts in anti-submarine warfare, including patents registered by Chinese researchers.

For example, the state-owned China Electronics Technology Group Corporation filed a patent in 2020 for magnetic anomaly detection, a technology first used in World War II to detect submarines through the effect of these large metal objects on the Earth's magnetic field.

China is developing systems to hunt US submarines from the air

China is turning to the air to try to protect its ships and aircraft carriers from attack by enemy submarines.

InsiderMichael Peck

This is a useful but limited system, which usually requires the plane to be flying less than 2km from the target, and which can only detect the presence of a submarine and not its route - meaning that it has to be complemented with a network of other sensors in order to target the hidden submarine.

But according to the patent now submitted, the Chinese scientists intend to use highly sensitive atomic magnetometers, which use lasers to detect changes in energy levels between atoms caused by fluctuations in a magnetic field.

“The CETC patent points to a technology that would allow an atomic magnetometer to detect the direction of a target and not just its existence,” Tirk and Salisbury say in their report.

Another patent, submitted in 2022 by the Aviation Industry Corporation of China, envisages a new system for operating sonobuoys, which are floating containers launched by aircraft and ships that detect submarines by emitting active sonar signals or passive sensors that detect the noise of a submarine.

In 2022, China overtook the United States in the number of military application patents registered.

China has also been improving the quality of training for its anti-submarine warfare units.

“The Chinese Navy has recognized its limitations and has begun to take steps to improve the quality of its anti-submarine warfare training, both in simulators and in physical training environments,” the report states.

“Units are training in more realistic conditions and breaking down the administrative barriers that prevented them from creating more training opportunities in different operational environments,” the study adds.

According to Tirk and Salisbury, in 2015 training materials began to emphasize the need for anti-submarine warfare aircraft and ships to work closely together, which is common practice in the US and Western navies.

Currently, the Chinese People's Liberation Army Navy still has a small ocean surveillance fleet and an incipient submarine surveillance capability.

Until now, the dozens of US nuclear submarines and its 12 aircraft carriers have ensured the unchallenged naval supremacy of the powerful fleets of the US Navy.

The scenario is changing.