By Ainur Rohmah
JAKARTA, Indonesia
A stall warning alarm sounded for four minutes before AirAsia Flight QZ8501 crashed into the Java Sea, Indonesian investigators said Thursday.
Mardjono Siswosuwarno, head investigator of Indonesia's National Transportation Safety Committee, told a press conference in Jakarta said the warning system could have been triggered by the angle of the plane’s ascent.
"Usually the stall warning beeps if the plane is in a state of pitch at an angle of more than 8 degrees," Siswosuwarno said.
He added that the plane rose from 32,000 feet (9,800 meters) to about 37,000 feet in 30 seconds before beginning to descend and was still in a stall when flight recordings ended seconds before impact.
The airliner from Surabaya, Indonesia, to Singapore crashed in bad weather on Dec. 28, killing all 162 people aboard.
Earlier this month, Transport Minister Ignasius Jonan said the plane was gaining altitude at a rate of around 6,000 feet a minute shortly before it stalled and disappeared from radar screens.
He likened the rate of climb to the capabilities of jet fighters rather than commercial aircraft.
The last contact with air traffic controllers was when the pilot asked to climb from 32,000 feet to 38,000 feet to avoid storm clouds. The flight was denied immediate permission to climb due to heavy air traffic and four minutes later the plane vanished.
Siswosuwarno also revealed that French co-pilot Remi Plesel, 46, was in control of the Airbus 320-200 when it started climbing while Captain Iriyanto monitored the instruments.
He said: "The second in command, or co-pilot, was sitting to the right of the cockpit. It was him who was flying the plane. The captain sat to the left of him as the pilot monitoring."
The voice cockpit recorder -- one of two black box recorders -- indicated that Plesel had been flying since take-off.
Iriyanto, 53, a former air force pilot with about 20,000 flying hours, is thought to have taken over control of the aircraft from the less experienced Plesel when it started to ascend and then descend, Siswosuwarno added.
The Tribunnews.com website, quoting Siswosuwarno, said the flight crew was properly certified and the plane was in an airworthy condition.
He said weather conditions consisted of clouds up to 44,000 feet. Indonesia’s weather agency said shortly after the disaster that the bad weather was likely to have been a factor.
At the moment of impact with the sea, Siswosuwarno said the flight was "probably" in a horizontal position, with the nose slightly higher than the tail.
Meanwhile, fishermen in West Sulawesi reportedly found a female passenger’s body more than 500 miles (800 kilometers) from the crash site.
The Kompas.com news website cited police officials as saying the remains belonged to the third corpse found in the past two days in the area of Majene.
AirAsia announced Thursday that 73 bodies have been recovered from the sea.
