Kyrgyzstan national Aidana Baizieva may have been actively involved in the helicopter's flight that crashed in Selangor, Malaysia, earlier this month, according to data from the black box.
The cockpit voice recorder suggested that the helicopter could have been operated by both the pilot, Captain Clifford Fournier, and company assistant, Ms Baizieva, reported The New Straits Times (NST).
The helicopter, which was also carrying Rompin MP Jamaluddin Jarjis, the Malaysian prime minister's principal private secretary Azlin Alias, businessman Robert Tan and bodyguard Mohd Razkan Seran, crashed on April 4 with no survivors.
A source told NST on Monday: "There is nothing wrong with Fournier bringing his friend on board the flight or her sitting next to him.
"The data, however, suggests that (Baizieva) was actively participating in the flight operations ... It should not have been that way."
The source added that the duo's exchanges were mainly on the flight's operations and that the recording would be used in the course of the investigation.
Ms Baizieva, 25, had apparently been taking flying lessons from Capt Fournier.
The helicopter was flying at about 610m over Semenyih before it suddenly dropped altitude, NST reported.
The voice recorder also revealed that while the passengers were "very chatty" as the helicopter flew from Kuantan, nobody said anything for a while before it went down.
This includes the pilot and Ms Baizieva, who was in the co-pilot's seat.
Said the source: "Those on board spoke on various subjects irrelevant to the ongoing investigation ... then there was a lull for several minutes right up to the crash.
"But let there not be any speculation on this, as their going quiet could be due to many reasons, including fatigue."
The source added that investigators believe that there was an explosion on board before the helicopter went down.
"Based on investigations at the crash site, investigators concluded that some parts of the helicopter were blown off in the explosion," he said.
Aviation expert Associate Professor Mohd Harridon Mohamed Suffian said that parts of the helicopter could have come apart at roughly 460m from the ground, due to the scatter of the debris from the helicopter.
He said that if witness accounts were true, the explosion would have severed the communication cable device and cockpit voice recorder.
This article was first published on April 15, 2015.
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