(Yicai Global) Nov. 28 -- China has made progress in its efforts to independently develop a manned submersible capable of dives in deep ocean. Trepanning has been completed for the entrance and exit and the observation window for the submersible's spherical cabin, CCTV reported.

Plans are afoot to conduct a sea trial in 2020 at the bottom of the Mariana Trench, the deepest area of seabed at more than 10,000 meters.

The manned spherical cabin, built with titanium alloy, is the major activity area for aquanauts, and includes entrance & exit and observation windows.

A simulation stress test will take place in the first half of next year for 10,000-meter depth oceans. The service life of the submersible is estimated to be 30 years.