Investigator: AirAsia plane wobbled, climbed and triggered stall warning
Before AirAsia Flight QZ8501 crashed, the co-pilot was flying the plane as the more experienced pilot monitored the flight. And things may have gone wrong in a span of just three minutes and 20 seconds, triggering a stall warning that sounded until it crashed into the Java Sea.
Those are the new details released by the Indonesia’s National Transportation Safety Committee in a news conference Thursday.
While it’s common for the co-pilot to be in control of the aircraft, significant questions still linger over the crash of the AirAsia jet. Why did the plane start a sudden, steep ascent? Was bad weather a factor?
The AirAsia Flight QZ8501 crashed on December 28 as it flew from the Indonesian city of Surabaya toward Singapore. There were 162 people on board.
The plane was in good condition and entire crew were all certified, said Mardjono Siswosuwarno, the chief investigator for the transportation committee.
The plane was veering left and wobbling, said Ertata Lanang Galih, a senior pilot and investigator with the committee.
Flight QZ8501 then ascended to 37,400 feet in about 30 seconds in a steep ascent, said Mardjono.
Commercial planes are not designed to ascend so quickly, analysts have said. It may have been climbing at a rate twice as fast as it could and should, one analyst told CNN.
The stall warnings — which blare the words “Stall, Stall” — went on as the plane started the steep climb and continued until it crashed, according to information on the flight data recorder. The voice warning doesn’t always mean the aircraft has stalled, said Mardjono. The warning can be triggered when the angle of attack, which is the angle at which the wing tackles the oncoming wind, hits eight degrees.
The plane dropped quickly, falling to 24,000 feet, out of radar detection.
Air traffic control permitted the plane to ascend to 34,000 feet about four minutes after the pilot’s initial request.
Officials have said previously that the aircraft climbed rapidly before it fell into the water. Last week, Indonesia’s transportation minister Ignasius Jonan told reporters that the AirAsia jet stalled after its sudden ascent.
Investigators have submitted their preliminary report into the crash, officials said. But Tatang Kurniadi, the chief of the National Transportation Safety Committee, said they would not release the preliminary report during a Thursday news briefing.
It’s unclear if or when the initial report will be released fully to the public. While the preliminary report presents facts, officials indicated there isn’t enough verification yet.
Source: CNN
