AirAsia 8501 found to have crashed on rudder fault

AirAsia Flight 8501's pilots effectively wrestled each other at the controls as they sought to fight off an electronics-system failure, dooming the plane and the lives of all 162 people on board last year, Indonesian crash investigators found.

A crack in the soldering of the rudder system caused the plane to exit autopilot, then start rolling sideways and upward, according to a report released on Tuesday by Indonesia's National Transportation Safety Committee. The two pilots then tried to control the aircraft in opposing ways, leading the plane to stall.

"What the captain was doing wasn't in line with the co-pilot," head investigator Nurcahyo Utomo told reporters in Jakarta. "The captain pulled while the co-pilot pushed so the recovery wasn't effective."

Last December's crash of the Airbus A320 drew further attention to aviation safety in Asia as it occurred months after the disappearance of Malaysia Airlines Flight 370 and the downing of Malaysia Airlines Flight 17. AirAsia is seeking to move on from the tragedy as it braces for its slowest revenue growth in at least a dozen years.

"It's the airline's responsibility to keep the aircraft in good shape to fly and the crew to respond accordingly," said Shukor Yusof, founder of Endau Analytics. "It will have a negative impact on AirAsia as a whole."

AirAsia Group Chief Executive Officer Tony Fernandes said he won't leave any stone unturned to make sure the industry learns from the accident. "There's much to be learned here for AirAsia, the manufacturer and the aviation industry," Fernandes said on Twitter.

As a result of the pilots' actions, the committee said it's recommending plane maker Airbus Group SE to have connected cockpit control sticks similar to those in rival Boeing Co planes.

Airbus said in a statement that it's studying the report's contents.

Investigators examined aircraft maintenance records and found 23 instances of rudder-system problem in the last 12 months, with the interval of occurrence becoming shorter in the last three months, according to the report. The investigation also found AirAsia's post-flight maintenance not optimal, as it failed to detect the repeated defects, Utomo said.

The investigation report recommended all pilots be trained in taking over controls during a crisis and that Airbus have mandatory recovery training for all pilots using its aircraft. Flight 8501 was en route to Singapore from Surabaya on December 28 when the plane lost contact with air-traffic controllers soon after they gave permission to ascend to 34,000 feet amid bad weather.

The plane, operated by Malaysia-based AirAsia's Indonesian affiliate, reached 38,000 feet before the plane stalled and started falling by 20,000 feet per minute, Utomo said.

Satellite images had shown storm clouds that reached as high as 44,000 feet, investigators had said earlier.

The committee found no indication that weather was a factor in the crash, Utomo said.

Debris from the AirAsia crash was spotted in the Java Sea on December 30, and the jet's fuselage was found on the seabed two weeks later.

At least three crashes - an airforce plane carrying civilians, a PT Trigana Air Service plane and a 10-person flight by PT Aviastar Mandiri - by Indonesian carriers have occurred since AirAsia's, increasing scrutiny on a market already faced with accidents and oversight issues.