According to the report, the new Chinese submarine would be capable of travelling from Shanghai to San Francisco in an incredible 100 minutes, splitting the vast Pacific through the use of supercavitation. While the idea of travelling roughly 9,875 km (6,135mi) in well under two hours seems fantastic, its underlying technology has been proven to work.
Back in the 1940s Russian engineers experimented with and built a supercavitating torpedo named the Shkval. Capable of reaching 370 km/h (229 mph) the soviet water-jet was significantly fast than any other torpedo ever built. This quantum leap in speed was due to the fact that the torpedo created a pocket of air around its body, negating the crippling drag effects of water. Though a massive increase in speed would be required to achieve the Chinese dream of rapid, trans-pacific submarining, that’s hardly the most critical issue handicapping supercavititating technology.
While the Soviets were experimenting with the Shkval they found their torpedo had two challenging flaws. The first was that any supercavitating object would have to enter the water at speeds in excess of 100 km/h in order to create a supercavitating bubble. Though that energy intensive hurdle could be overcome once in the water the Shkval also had little maneuverability, relegating the technology to use in unmanned craft.
According to Li Fengchen, a professor of fluid machinery and engineering, “By combining liquid-membrane technology with supercavitation we can significantly reduce the launch challenges and make cruising control easier."
Apparently, introducing a small amount of liquid to a supercavitating slipstream lends enough friction to the systems that one can effectively pilot a supersonic submarine. Though one obstacle in the Chinese supersonic plan appears to be solved Li and his collegues admit a great deal of work is still to be done.
When a supersonic submarine prototype will be ready for field tests is anyone’s guess, but given China’s technological ambitions a 100-minute trip across the Pacific might be a very real travel option within a few generations.
Image Courtesy of the South China Morning Post