Mozambican carrier LAM is to request further details from investigators over preliminary findings which suggest the fatal loss of its Embraer 190 was the result of deliberate action.
None of the 33 occupants survived after the twinjet came down in northeast Namibia while en route from Maputo to Luanda on 29 November.
The aircraft had been cruising at 38,000ft but then entered a rapid descent before contact was lost.
While a formal preliminary report has yet to be released, the Mozambican civil aviation institute is widely cited as stating that the captain locked the first officer out of the cockpit, before resetting the selected altitude three times.
Reports quoting the Mozambican state news agency, AIM, say that the institute’s chief Joao Abreu, during a briefing, said: “During these actions you can hear low- and high-intensity alarm signals and repeated beating against the door with demands to come into the cockpit.”
The reasons for the actions are undetermined, he added, but illustrate a “clear intention” to sabotage the flight.
LAM has expressed “deep concern and shock” over the initial findings from the inquiry into the loss of flight TM470.
It says it will seek a detailed report in order to examine the facts which have led the investigators to reach these conclusions.