• Analyst says the collision may have damaged its sonar dome, the sensor system 
  • An expert believes something like an underwater drone hit the submarine 
  • The collision may have happened near Chinese-administered Paracel Islands

A month after U.S. nuclear submarine USS Connecticut hit an unknown object while moving submerged in the South China Sea, there is not much information on what exactly happened — but satellite images indicate that the damage may be below the waterline.

However, Macau-based military observer Antony Wong Tong believes that the USS Connecticut suffered a head-on collision. 

"It’s almost certain that the USS Connecticut was hit in a head-on collision that cracked its sonar dome, the most important sensor system, meaning the sub became effectively blind and deaf underwater and had to escape immediately," he told South China Morning Post.

The first publicly available image of the submarine shows that the collision occurred well below the vessel's surfaced waterline, such as on the bottom of its hull. This rules out a full head-on collision, or one from above, in which case the sail would have borne the impact, reported The Drive.

The images of the submarine, moored at the United States Navy’s base in Guam, were captured by a private earth-imaging company Planet Labs on October 20. Nothing on the sail or other parts of the hull was cracked, implying its nuclear reactors remained normal.  

The accident that occurred on October 2 left 11 crew members injured. The U.S. Navy said in a statement that the submarine's nuclear propulsion plant and spaces had not been affected. No further updates were given.

Wong believes the collision may have happened close to the exclusive economic zone claimed by China near Paracel Islands. However, the U.S. does not recognize the region as Chinese territorial waters and considers it international waters. 

Recent satellite images posted on Twitter by Beijing-based maritime think tank the South China Sea Strategic Situation Probing Initiative too hints that the Seawolf-class submarine had been spotted sailing 43 nautical miles southeast of Paracel Island on October 3, the day after the apparent collision.

"The fact that the American sub could stay underwater for so long suggests the damage was not serious," he added. 

Beijing-based naval expert Li Jie told the South China Morning Post that the Chinese navy may have been aware of the sub’s route through the region but did not establish where the incident occurred and just let it pass. 

"The damage could have been caused by something the size of an underwater drone, rather than another submarine," Li said.

While the vessel is now in Guam for evaluation and repairs, Chinese officials have accused the U.S. of concealing details of the incident from Beijing. 

Chinese foreign ministry spokesman Zhao Lijian had urged the U.S. to make clarifications with regard to the incident. Chinese state-backed Global Times recently ran an article quoting experts who said the U.S. submarine was sailing on a "location where it is not allowed to be for a covert spy operation, but failed to effectively grasp the underwater situation and resulted in the collision."

USS Connecticut File image of USS Connecticut. Photo: U.S. Pacific Fleet