China's manned deep-diving team returned on Monday after completing a milestone 56-day Arctic expedition that began on July 22. During the mission, the team conducted a series of scientific surveys and tests. The Tansuo-3, the world's first icebreaking-capable manned submersible mothership, completed 43 dives with the Fendouzhe submersible. Working alongside Jiaolong, it achieved the first-ever dual-submersible operation under Arctic ice, marking China the only country to conduct continuous manned deep dives in dense Arctic sea-ice zones.