The probe into the November crash of an Air New Zealand (ANZ) Airbus A320 in France is focusing on an apparent surge of engine power during the final approach which caused the aircraft to pitch up and stall.
Head of the investigation, Jean-Pierre Dreno, told New Zealand's TV3 television that the cockpit crew were struggling to control the A320 during its final approach to Perpignan before the aircraft crashed into the Mediterranean Sea.
Describing the final seconds of the flight, Dreno said data retrieved from the flight data recorder (FDR) showed the aircraft first pitched up suddenly before it fell "on its side" into the sea. He said it all happened "very quickly".
Dreno also revealed that the cockpit voice recorder (CVR) captured sounds from the crew in the final moments of the flight, adding of the pilots that "they screamed".
The aircraft crashed on 27 November as it was coming in for a landing after carrying out a pre-delivery test flight. ANZ was preparing to take the aircraft back off lease from Germany's XL Airways and the crash killed all seven people on board including five New Zealanders.
French investigators initially found they were not able to retrieve data from the CVR or FDR but the manufacturer Honeywell was able to successfully retrieve the data earlier this month.
The French Bureau d'Enquetes et d'Analyses (BEA) began analysing information from the devices last week.
ANZ is cautioning, however, that French authorities "still do not know the cause of the A320 accident".
CEO Rob Fyfe says he met with chief prosecutor Dreno yesterday to seek an update on the investigation and "he made it quite clear to me that there are several more weeks of detailed analysis required before the investigating team has a clear idea of a likely cause".
Fyfe adds: "He reiterated his comments over the weekend that investigators are clear on the flight path and the fact that power was applied to the aircraft's engines but how or why is not known at this stage, and that he is concerned by speculation fuelled by media reports."