China showcases deep saturation diving capability in South China Sea

This file image shows a PLAN Dakai-class submarine rescue ship, Xi Hu 841. (Japan MoD)

China has for the first time publicly shown footage of the People's Liberation Army Navy (PLAN) conducting full-cycle saturation diving operations.

The footage suggests that the PLAN's Dakai (Type 927)-class vessels are being operationalised as support nodes for deep-ocean engineering operations in addition to their core role as submarine rescue ships.

It also highlights China's efforts to develop frontline combat platforms alongside the enabling systems required to support sustained operations in the undersea domain.

The report, aired by state-controlled China Central Television (CCTV)-7 on 19 June, shows a Southern Theatre Command naval rescue detachment conducting deep-sea diving training in the South China Sea.

It follows a team of divers completing a full saturation diving cycle, a process that allows personnel to operate at extreme depth for extended periods.

According to CCTV, divers were first placed in a hyperbaric environment aboard the support vessel, where pressure was gradually increased to simulate conditions at approximately 300 m depth.

Once saturation was achieved, the divers were transferred to a diving bell, which was lowered into the water from the ship to conduct subsea operations.

The segment shows elements of the diving support system, including deck compression chambers, bell handling equipment, and control facilities used to monitor the divers during the mission.

After completing their tasks, the divers returned to the bell and were brought back aboard the vessel, where they began a decompression phase lasting up to several weeks.

The operations were conducted from the first-of-class Type 927 vessel Jingpo Hu (