The debris of the ill-fated Indian Coast Guard (ICG) Dornier aircraft, which crashed into the sea more than a month ago, was finally found on Friday in the Bay of Bengal, 20 nautical miles south-east of Cuddalore.
The fate of the three crew members aboard, however, was not known, and there is no clarity now on how long the search for them will continue.
Coast Guard IG S P Sharma said ships involved in search operations found the black box about 16 nautical miles off the Pichavaram coast near the Cuddalore district of Tamil Nadu, where it was last seen.
Explaining the process involved in locating the aircraft, inducted in the service in 2014, Sharma said Indian naval Submarine Sindhudhvaj, on redeployment for locating the missing aircraft, picked up a barrage of transmissions at a depth of 996 m on July 6.
“This was a vital source for deployment of the Reliance vessel MV Olympic Canyon to localise the search,” he said, adding: “Consequently, the uninterrupted search, which included 693 hours of surface effort and 196 hours of air effort, yielded positive results.”
Sharma said the Multi-functional Support Vessel (MSV) of Reliance India Limited with integrated Remotely-Operated Vehicle (ROV) was able to locate and recover the Flight Data Recorder (FDR) and a Line Replacement Unit (LRU) from a depth of 950 m in a unique and first-ever salvage at such depths. “Some parts of the aircraft were also found,” he said.
Pointing out that the FDR could provide vital inputs in establishing the incident’s cause, the official said: “This is a major accomplishment to the unprecedented search operation which was launched about a month ago.”
However, the fate of the three crew members — Pilot Vidyasagar from Andhra Pradesh, Co-Pilot Subash Suresh from Chennai and Navigator or Observer, as being called in Naval parlance, M K Soni of Bhopal — were not known.
During the operation, a rescue ship belonging to the ICG sighted a multi-colour sheen of oil in concentric circles which indicated oozing of oil. But the samples sent for laboratory analysis showed it was not aviation fuel.
Apart from deploying Sindhudhvaj for sub-surface search, the MSV, along with 10 ICG and Naval ships and two aircraft were also pressed into service for the search.
The Dornier aircraft CG-791, deployed for surveillance along the Tamil Nadu Coast and Palk Bay from the Coast Guard station Chennai on June 8 evening failed to return to base. It lost contact with the base around 2100 hours.
A radar at Trichy tracked the aircraft till 2123, at a location 95 nautical miles south of Chennai near Karaikal. Then it went off the screen.
The radar data also suggested that the aircraft lost height fast, triggering suspicion of serious malfunctioning of systems. This was the second incident involving a Dornier aircraft crashing into the sea during nocturnal flight in the past three months.