TEHRAN, Young Journalists Club (YJC) - Voyage data recorder, or VDR, is a data recording system designed for all vessels required to comply with the IMO's International Convention SOLAS Requirements (IMO Res.A.861(20)) in order to collect data from various sensors on board the vessel.
He said that some questions about the incident would be answered this week.
Finding answers to the questions needs complete evaluation of the incident which would be carried out by Chinese maritime authorities and in presence of all involved sides, he said.
The Iranian ship, Sanchi -- carrying 136,000 tons (almost one million barrels) of ultra light crude oil from Iran -- had been in flames for eight days, since it collided with a cargo ship off the coast of China on 6 January, according to Presstv.
The vessel finally went down on Sunday after a new and massive fire erupted, sending a cloud of black smoke as high as one kilometer (3,280 feet) above the East China Sea.
The fire from the sunken tanker was extinguished on Monday, according to China Central Television (CCTV), but Chinese authorities say there are still concerns about major pollution to the sea bed and surrounding waters off Chinese coast.