MH370: Chinese Search Vessel Returns Home

Dong Hai Jiu 101
Dong Hai Jiu 101

By MarEx 2016-12-07 16:39:30

The Dong Hai Jiu 101 has concluded its involvement in the underwater search for the missing aircraft MH370 and is preparing to return to Shanghai.

The vessel will sail to Fremantle, Australia, to demobilize the Phoenix Remora III remotely operated vehicle (ROV) that has completed 33 dives since October 2016. 

Flight MH370 disappeared in March 2014 with 239 passengers and crew on board en route to Beijing from Kuala Lumpur. Searchers led by engineering group Fugro have been combing an area roughly the size of Greece for two years.

Search operations moved from deep tow operations to autonomous underwater vehicle (AUV) and ROV operations at that time. Deep tow vehicles are equipped with side scan sonar and multibeam echo sounders, making them ideal for searching large areas of the seafloor in a single pass. They are towed behind the vessels on 10 kilometer-long (six mile-long) cables and while they require reasonable conditions to safely launch, once they are in the water they can remain deployed for days at a time.

Areas of the seafloor that are difficult or inefficient to search using the deep tow vehicles, for example areas with irregular terrain have been searched using an AUV. The AUV is also used to reacquire sonar contacts which require further investigation. The AUV must be launched and recovered in relatively calm sea conditions which limit these operations to the better summer weather months in the search area.

The ROV on Dong Hai Jiu 101 has been used to reacquire, investigate and eliminate sonar contacts of potential interest identified during previous deep tow and AUV search operations. The vessel must remain geostationary over the top of the ROV during a dive and therefore these operations must also be conducted in calmer sea conditions. 

The sonar contacts acquired by the ROV have been shown to be mainly geology with some manmade items, including cables and drums, which have no relationship to MH370.

Fugro Equator, the last vessel being used in the search, is expected to complete missions in the remaining parts of the 120,000 square-kilometer search area in January/February 2017. Due to poor weather conditions over the Southern hemisphere winter, searching the entire 120,000 square-kilometer underwater search area has taken longer than first planned. 

At a meeting of Ministers from Malaysia, Australia and the People’s Republic of China held on 22 July 2016, it was agreed that should the aircraft not be located in the current search area, and in the absence of credible new evidence leading to the identification of a specific location of the aircraft, the search would be suspended upon completion of the 120,000 square-kilometer search area.

Should credible new information emerge that can be used to identify the specific location of the aircraft, consideration will be given to determining next steps.