Malfunctions, Pilot Response Blamed in AirAsia Flight 8501 Crash
Investigators’ report depicts confusion and escalating trouble in plane’s cockpit
The Wall Street Journal
By BEN OTTO in Jakarta, Indonesia, and ANDY PASZTOR in Los Angeles
Updated Dec. 1, 2015 5:16 a.m. ET
Indonesian investigators said the crash of AirAsia Flight 8501 last year, which killed all 162 people on board, was caused by a combination of system malfunctions and improper pilot responses to cascading electrical and rudder-system problems.
Investigators from Indonesia’s National Transportation Safety Committee said Tuesday that a cracked solder joint on the Airbus A320 resulted in an electrical interruption that prompted computer-generated warnings of a rudder malfunction.
The problem occurred four times during the flight. The first three times, the flight crew responded according to standard procedure, investigators said. The fourth time, however, the flight-data recorder indicated actions were taken similar to those of circuit breakers being reset. That led the autopilot to disengage.
Soerjanto Tjahjono, chief of the committee, told The Wall Street Journal that it appeared that a member of the flight crew had reset the circuit breakers. If a pilot had done that, he would have had to leave his seat, Mr. Tjahjono said. He said that three days before the flight, the captain had encountered the electrical problem on the same jet on the ground and had seen a maintenance crew resolve it by resetting the circuit breakers. Mr. Tjahjono said Airbus Group SE permits resetting the circuit breakers, as long as “you know the consequences.”
The reset turned off both the plane’s autopilot and auto-thrust system, and the pilots didn’t turn them back on, investigators said, leaving them to manually fly with a degraded and unfamiliar fly-by-wire system. But with normal flight protections gone, the faulty rudder controls put the plane into a steep bank while pilots flew higher. Investigators said the crew was unable to react appropriately to “a prolonged stall condition” ending in the crash.
The report depicts confusion and escalating trouble in the cockpit, with pilots deviating from course and asking air-traffic controllers to approve a climb to avoid a storm even as they confronted four separate rudder-system warnings within 15 minutes.
Roughly a minute after the fourth warning, according to the report, the co-pilot pulled the jet’s nose up sharply and that was followed quickly by a stall warning that “continued until the end of the [cockpit voice] recording.” The co-pilot’s control stick remained “mostly at maximum pitch up” until the crash, investigators determined.
Reflecting further lack of crew coordination, the report indicates the captain also was manipulating his control stick almost from the instant the stall warning activated to the time the flight-data recording ended. In an emergency, cockpit discipline requires one of the two pilots to take over the controls and make all flight inputs.
After six separate orders by the Indonesian captain to “pull down, pull down” the first officer, who was French, replied in his native language: “What is going wrong,” according to the report. That rise led to the fatal stall, Mardjono Siswosuwarno, lead investigator for the crash, said.
Investigators found the solder problem had come up 23 times in the previous 12 months, gaining in frequency in recent months. They suggested responses to the problem were inadequate. The circuit breakers had been reset three days earlier by mechanics during troubleshooting on the ground.
The report describes a series of discussions between ground staff and the flight’s captain, including an exchange in which the captain was told he could “reset [the breakers] whenever instructed” by computerized warning messages.
AirAsia Flight 8501 crashed in waters off the coast of Borneo island en route to Singapore from the Indonesian city of Surabaya on Dec. 28.
Airbus said it had received the final accident report and was carefully studying its contents. “Airbus has provided full technical assistance and expertise to the authorities in charge of the investigation,” the company added.
AirAsia Indonesia said it had introduced several safety initiatives before the release of the report, including upset-recovery training and implementation of an aircraft-maintenance and analysis system to provide real-time monitoring on aircraft fault messages.
The crash came years after international air-safety authorities recognized the dangers of high-altitude stalls with degraded fly-by-wire flight controls. They have urged stepped-up training to enhance manual flying skills of pilots so they could cope with precisely such types of emergencies.
Months ago, safety experts from Airbus and several airlines that operate A320s said that pulling or resetting circuit breakers in midair was considered hazardous and wasn’t part of any Airbus-authorized training program.
Such a move can have unpredictable consequences by causing automated flight-protections to disengage suddenly.
The global airline industry has been struggling to sharpen flying skills at a time cockpits are becoming increasingly automated. Several accidents have raised concerns that pilots lack the skills to respond to emergencies that simulators can’t replicate well.
An Air France Airbus A330 jet in 2009 crashed after crews lost some of their automatic flight controls and failed to recognize they were in a high-altitude stall. All 228 people on the flight from Rio de Janeiro to Paris died.
The same year, a Colgan Air turboprop crashed near Buffalo, N.Y. Investigators determined the pilot was never properly trained on how to respond to the type of emergency the aircraft encountered. All 50 people on the plane died.
Airbus said last year it was revising its pilot-training policies to place greater emphasis on manual flying skills.
In recent years, some airlines, including Delta Air Lines Inc., have sent a few of their most seasoned instructors back to flight school to learn how to detect and recover for airborne upsets.
Source: http://www.wsj.com
(CNN) —The way pilots responded to a technical malfunction resulted in the crash of an AirAsia flight into the Java Sea, killing all 162 people on board, investigators said Tuesday.
AirAsia Flight 8501 was en route to Singapore from the Indonesian city of Surabaya on December 28 last year when it crashed.
It was one in a string of aviation disasters that occurred in Asia in 2014, including the mysterious disappearance of MH370 over the Indian Ocean and the crash of TransAsia Flight 222 on a Taiwanese island.
In the AirAsia disaster, the system that regulates the plane's rudder movement kept malfunctioning because of a cracked solder joint. Aircraft maintenance records found it had malfunctioned 23 times in the year before the crash, and the interval between those incidents became shorter in the three months prior to the crash, Indonesia's National Transport Safety Committee said in a report.
"Subsequent flight crew action resulted in inability to control the aircraft ... causing the aircraft to depart from the normal flight envelope and enter a prolonged stall condition that was beyond the capability of the flight crew to recover," the report said.
In other words, "it's a series of technical failures, but it's the pilot response that leads to the plane crashing," CNN's aviation correspondent Richard Quest said.
Pilot training weakness
The investigation, a joint effort involving Australian, French, Singaporean and Malaysian authorities, points to weaknesses in pilot training in dealing with upsets, or when an aircraft is angled greater than 45 degrees.
"Our recommendation to AirAsia is to train their pilots flying the Airbus plane on how to make an upset recovery," investigator Nurcahyo Utomo said.
The AirAsia pilots had not been trained for that scenario, he added, because the manual provided by the plane's manufacturer said the aircraft, an Airbus 320, was designed to prevent it from becoming upset and therefore upset recovery training was unnecessary.
AirAsia has since required upset recovery training for its pilots, Utomo said.
Utomo also said the cockpit voice recorder showed confusing instructions from the captain to the co-pilot who was manning the controls at the time.
"The most interesting part that could be heard from the CVR is that whenever the plane went up, the captain said 'pull down.' ... To go down, the captain has to say 'push,' while to go up, the captain has to say 'pull' in reference to moving the side stick handle."
Cruising involves such high speeds, CNN's Quest said, that pilots responding without complete precision can often be disastrous.
"A huge amount of training is done on takeoff and landing and traditionally, of course, is 70-80% (of when accidents take place); only 10% takes (place) in the cruise phase of flight. But if something does happen in the cruise phase of flight, it does typically end up fatal."
Plane ascended rapidly before crash
Preliminary findings from Indonesia's NTSC earlier this year said roughly 35 minutes into the two-hour flight, the pilot asked air traffic control for permission to climb to avoid stormy weather.
The plane went from cruising at 32,000 feet, ascending steeply to 37,400 feet in about 30 seconds -- something commercial planes are not designed to do. It may have been climbing at a rate twice as fast as it could and should, one analyst told CNN.
Minutes later, the plane disappeared from radar.
Although the area was experiencing turbulent weather patterns, seven other planes flying nearby landed safely.
Malaysia-based AirAsia did not have the clearance to fly the route on that particular day.
Indonesia's NTSC issued several recommendations to AirAsia and Airbus as well as Indonesian, U.S. and European aviation regulatory bodies, but the statement did not detail what they are.
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 Bhd. 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.
Repeated Defects
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 Dec. 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 Dec. 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.
Source: http://www.bloomberg.com
Pilots need to be able to fly the plane when the vaunted automation isn't working. These guys didn't and a lot of folks died for their incompetence.
ReplyDeletePilots are there to react when other systems fail.