All 25 seafarers have been rescued without injury, but the 2,490-TEU containership remains adrift in the South China Sea, with the cause of the casualty and plans for recovering the vessel still unclear.

The MSC HERMES III remained unmanned and adrift in the South China Sea on Wednesday after all 25 crew members abandoned the containership a day earlier, leaving questions over what disabled the vessel and how it will be recovered.

A HYDROPAC navigational warning issued following the evacuation described the vessel as “derelict” and placed it near 11°45′N, 112°15′E. The warning is scheduled to remain in force until September 25.

The position is around eight nautical miles northeast of where the vessel transmitted its initial distress signal, indicating that the unmanned ship continued to drift after the crew left.

All 25 crew rescued

The Maritime and Port Authority of Singapore said its Maritime Rescue Coordination Centre received a distress alert from the Liberia-registered MSC HERMES III at about 08:45 Singapore time on September 22.

The ship was then within Singapore's Maritime Search and Rescue Region, roughly 300 km east of Vietnam.

Singapore's MRCC broadcast a request for nearby vessels to assist. Three ships responded, with the much larger containership MSC RUBY subsequently recovering all 25 crew members from a lifeboat after they had abandoned MSC HERMES III.

No injuries were reported.

The precise reason for abandoning the vessel remains unexplained publicly. Reports have suggested that a fire may have occurred onboard, but neither MPA nor MSC has publicly confirmed a fire as of September 23. There has also been no confirmed announcement of a towage or salvage arrangement.

From Shanghai and Hong Kong towards Jakarta

MSC HERMES III is a 2006-built, 2,490-TEU containership, with a deadweight of about 38,193 tonnes, gross tonnage of 27,061 and an overall length of 212 metres. Its IMO number is 9350317 and it sails under the Liberian flag.

Official Hong Kong Marine Department records show that the vessel arrived from Shanghai before departing Hong Kong on September 20 with Jakarta listed as its next port.

That puts the casualty on a voyage connecting major Asian container gateways through the South China Sea, one of the region's busiest commercial shipping areas.

The vessel is also listed by Steamship Mutual, which identifies Multi Container Management S.A. as the entered member for the ship.

Attention turns to the drifting vessel

With the crew safely recovered, attention is now shifting from search and rescue to the condition and recovery of MSC HERMES III.

An unmanned containership drifting at sea presents a different set of operational issues. Authorities and salvors will need to establish the vessel's propulsion and steering condition, structural integrity, fuel situation and cargo status before determining how it can be safely boarded or taken under tow.

Whether dangerous goods are among the containers onboard has not been publicly disclosed, and there has been no official indication of pollution or cargo loss.

The vessel's age — around 20 years — is also likely to attract attention, but there is currently no evidence linking its age or maintenance condition to the casualty.

For now, the most important unanswered question is what forced an entire crew to abandon a ship that subsequently remained afloat.

Until the casualty's cause and salvage arrangements are disclosed, MSC HERMES III will remain both a navigational concern and an unresolved casualty in one of Asia's most heavily travelled shipping regions.