China is developing a warship of naval theorists' dreams

Jeffrey Lin, Popular Science
1 June 2017

The Chinese navy is taking arsenal ships in a new direction—as giant submersibles. Post-Cold War naval theorists have long dreamed of recreating the old battleships' power through massive "arsenal ships," or warships carrying hundreds of guided missiles that could fire at land and sea targets. Now it looks like China wants to make that dream a reality.
Stories circulating on Chinese websites—including the Wuhan city government site—mention that Chinese institutions are conducting studies on gigantic submersible arsenal ships.
What's the big deal about an underwater arsenal vessel? Well submerging all or even most of a large warship would reduce its radar and visual signature, as well as protect it against most missile threats.
There are two concepts in circulation: one is a high-speed warship with much of its hull submerged but otherwise has a functional superstructure with defense weapons and radar, the other is almost completely submerged arsenal ship with two conning towers. The scale of the designs are significant; either ship would displace roughly about 20,000 tons at full load.
Reports claim there has been substantial design work and concept proofing for this underwater arsenal ship. Even on his deathbed, leading naval engineer Professor Dong Wei Cai continued to work on a key aspect of the arsenal ship design: the high-speed wave hydroplane.
For stealth operations, the arsenal ship would have most of its hull inherently submerged, with only the bridge and a few other parts of the ship above the waterline, reducing the radar cross section. But when traveling with a
high-speed naval taskforce, the arsenal ship will sacrifice stealth to use its flat hull bottom to hydroplane at high speeds, cutting across the waves like a speedboat or amphibious armored vehicle.
The second design is more conventional, it is essentially a giant, conventionally propelled submarine with two conning towers stuffed with snorkels, periscopes, and communications antennae. Given its need to keep up with high-speed surface ships and its lack of high-speed endurance underwater, this arsenal ship design would operate similarly to WWII submarines; the majority of its voyage will take place on the surface, and will submerge only during combat and under attack.
Chinese research institutes have been testing sub-models of both arsenal ship configurations since 2011, including open-water tests for the hydroplane arsenal ship and laboratory tests for the arsenal submarine. Unverified rumors on the Chinese internet claim that a full-scale, proof-of-concept is under construction at Bohai Shipbuilding Heavy Industrial Corporation, to be launched after 2020.