On February 8, a submarine quietly made its way along the Yangtze River in China – but this was no ordinary sub and no ordinary journey.
Somehow, someone managed to capture a video of this event, and it has military analysts completely puzzled.
Smaller than most United States or Russian submarines, notably nuclear-powered ones, this boat does not fit the expected trend.
According to a report in Naval News, the Chinese Navy (PLAN) sub might be sophisticated, but it does not neatly fit into the array of types currently fielded by other major navies. China is, it appears, doing its own thing.
The submarine, tentatively designated Type-039C/D by western observers (also dubbed “Olympics” class after the Beijing Games), was clearly visible in a short video clip recently uploaded on Chinese social media.
After attracting attention, it was later deleted – but not before some key information was gathered by experts at Naval News.
The location along the Yangtze River is downstream from the China Shipbuilding Industry Corporation shipyards in Wuhan, which are known for building submarines, Naval News said.
And it was traveling toward Shanghai where other Wuhan-built subs are moved to for fitting out. The new design is in the order of 50 meters long, compared to 77.6 meters for the in-service Yuan class.
According to Popular Mechanics, the submarine has an oddly shaped sail: a large, dorsal fin-shaped protrusion on top where the periscope, snorkel, and sensors are mounted.
Experts at The Drive said the sail on the new sub is very similar to Sweden’s next-generation A26 Blekinge class submarine. On the Swedish boat, this feature is understood to have been chosen to increase its stealth characteristics.
Instead of being smooth and featureless like other submarines, the Type-039C/D’s sail features straight angles and facets. Why the faceting? Experts speculate that the fin shape is designed to reduce its radar signature.
Diesel-electric subs require air for their engines to operate, and so they must remain surfaced or at snorkel depth to operate.
Unlike nuclear subs, which can cruise at depth for weeks at a time, non-nuclear boats often spend a great deal of time on or near the surface, only submerging once at their patrol area or when they expect enemy contact, Popular Mechanics reported.
Many modern anti-submarine aircraft, such as the US Navy’s P-8 Poseidon, utilize long-range radar to detect surfaced submarines or submarine snorkels or periscopes.
An airplane with a long-range radar could detect a surfaced submarine from many miles away, before the sub spots it, and then close in for the hunt.
A stealthy sail, however, would allow the Type 39C/D to leave port and travel the hundreds of miles to its destination surfaced with less of a chance of being detected.
The sub likely also has an air-independent propulsion system, which can power a submerged submarine for up to two weeks at a time.
The fact China continues to focus on developing conventionally powered submarines, in contrast to the all-nuclear US Navy, is significant.
Traditionally small submarines have been less capable, which is largely why major navies do not field them. Although cheaper to build, they compromise on performance, range and speed, Naval News said.
But this balance may actually be changing. New lithium-based battery technologies may offer small submarines much longer endurances. And higher cruising speeds.
This may significantly increase their combat utility, particularly inshore where their small size poses an advantage.
Increases in battery power may also allow more powerful sonars and combat systems to be carried.
What exactly, is this sub’s purpose?
One theory is that it was built for export because the design is similar to the CSIC concepts shown abroad. Myanmar, Bangladesh and Sri Lanka might be candidates.
Yet white stripes running along the top of the sail may indicate that it is for the Chinese navy. These are normally seen on submarines before they are commissioned, Naval News said.
According to EurAsian Times, the sub is expected to be armed with a variety of weapons, such as wire-guided torpedoes, anti-ship missiles, and mines. It may also carry land-attack cruise missiles.
If the PLAN is going to operate this new type, it represents a greater deviation from other leading navies’ strategies. But as small subs become more capable, they may play a valuable role for Beijing.
The South China Sea and island chains seem particularly well suited.