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Malaysia Backtracks on When Airliner’s Communications Were Disabled
Computer Sent Missing Plane Off Flight Path
(about 7 hours later)
SEPANG, Malaysia — The investigation into the disappearance of Malaysia Airlines Flight 370 took another confusing turn on Monday, as the authorities here reversed themselves and offered yet another version of the sequence of events in the crucial minutes before ground controllers lost contact with the jet early on March 8.
WASHINGTON — The first turn to the west that diverted the missing Malaysia Airlines plane from its planned flight path from Kuala Lumpur to Beijing was carried out through a computer system that was most likely programmed by someone in the plane’s cockpit who was knowledgeable about airplane systems, according to senior American officials.
As the search for the missing Boeing 777 jet stretched into a 10th day, two of the nations helping in the hunt, Australia and Indonesia, agreed to divide between them a vast area of the southeastern Indian Ocean, with Indonesia focusing on equatorial waters and Australia beginning to search farther south for traces of the aircraft. To the north, China and Kazakhstan checked their radar records and tried to figure out whether the jet could have landed somewhere on their soil.
Instead of manually operating the plane’s controls, whoever altered Flight 370’s path typed seven or eight keystrokes into a computer on a knee-high pedestal between the captain and the first officer, according to officials. The Flight Management System, as the computer is known, directs the plane from point to point specified in the flight plan submitted before each flight. It is not clear whether the plane’s path was reprogrammed before or after it took off.
The Malaysian authorities said on Monday that the plane’s first officer — the co-pilot — was the last person in the cockpit to speak to ground control. But the government added to the confusion about what had happened on the plane by that time, withdrawing its assertion that a crucial communications system had already been disabled when the co-pilot spoke.
The fact that the turn away from Beijing was programmed into the computer has reinforced the belief of investigators — first voiced by Malaysian officials — that the plane was deliberately diverted and that foul play was involved. It has also increased their focus on the plane’s captain and first officer.
Hishammuddin Hussein, Malaysia’s defense minister and acting transportation minister, had made that assertion on Sunday, saying that the aircraft’s Aircraft Communications Addressing and Reporting System, or Acars, was disabled at 1:07 a.m. Saturday, well before the co-pilot’s verbal signoff. That appeared to point to possible complicity of the pilots in the plane’s disappearance.
Prime Minister Najib Razak of Malaysia told reporters on Saturday that his government believed that the plane had been diverted, because its transponder and other communications devices had been manually turned off several minutes apart. American officials were told of the new information over the weekend.
But Ahmad Jauhari Yahya, the chief executive of Malaysia Airlines, said at a news conference early Monday evening that the Acars system had worked normally at 1:07 but then failed to send its next regularly scheduled update at 1:37 a.m., and could have been disabled at any point between those two times. “We don’t know when the Acars system was switched off,” he said.
But Malaysian authorities on Monday reversed themselves on the sequence of events they believe took place on the plane in the crucial minutes before ground controllers lost contact with it early on March 8. They said it was the plane’s first officer — the co-pilot — who was the last person in the cockpit to speak to ground control. And they withdrew their assertion that another automated system on the plane called Aircraft Communications Addressing and Reporting System, or Acars, had already been disabled when the co-pilot spoke.
Mr. Ahmad Jauhari said the co-pilot’s verbal signoff was given by radio at 1:19 a.m., and the aircraft’s transponder, which communicates with ground-based radar, ceased working about two minutes later.
The Flight Management System reports its status to Acars, which in turn transmits information back to a maintenance base, according to an American official. Acars ceased to function about the same time that oral radio contact was lost and the airplane’s transponder also stopped, fueling suspicions that foul play was involved in the plane’s disappearance.
The new account appeared to reopen the possibility that the aircraft was operating normally until 1:21 a.m., and that the two communications systems failed or were deactivated at the same time, not at separate points. That could raise additional questions about whether the plane was deliberately diverted, or experienced mechanical or electrical difficulties that crippled its communications and resulted in its flying an erratic course.
Investigators are scrutinizing radar tapes from when the plane first departed Kuala Lumpur because they believe the tapes would show that after the plane first changed its course, it passed through several pre-established “waypoints,” which are like virtual mile markers in the sky. That would suggest that the plane was under control of a knowledgeable pilot, because passing through those points without using the computer would have been unlikely.
Though the possibility of an accident has not been excluded, the strong consensus among Malaysian and foreign experts involved in the investigation remains that deliberate action by someone on board was the most likely explanation for the disappearance, according to a person involved in the investigation. This person, who insisted on anonymity because he was not authorized to discuss publicly a matter that has become a criminal case, said investigators believed there were too many suspicious coincidences for the disappearance to have been entirely due to an accident.
According to investigators, it appears that a waypoint was added to the planned route. Pilots do that in the ordinary course of flying if air traffic controllers tell them to take a different route, to avoid weather or traffic. But in this case, the waypoint was far off the path to Beijing.
Standing next to Mr. Ahmad Jauhari at the news conference, Mr. Hishammuddin waved off numerous questions about why he had said a day earlier that Acars had been disabled at 1:07 a.m. “What I said yesterday was based on fact, corroborated and verified,” he said. In response to another question, he said that uncertainty about the chronology underlined the importance of finding the aircraft and its data recorders.
Whoever changed the plane’s course would have had to be familiar with Boeing aircraft, though not necessarily the 777 — the type of plane that disappeared. American officials and aviation experts said it was far-fetched to believe that a passenger could have reprogrammed the Flight Management System.
After the last voice contact with the ground, radar data indicates that the aircraft turned off its planned flight path northeastward toward Beijing, and had headed west, back across the Malay Peninsula while rising in altitude and falling rapidly again, and then flew out over the Strait of Malacca and beyond, out of radar range, to an unknown location.
Normal procedure is to key in a five-letter code — gibberish to non-aviators — that is the name of a waypoint. A normal flight plan consists of a series of such waypoints, ending in the destination airport. For an ordinary flight, waypoints can be entered manually or uploaded into the F.M.S. by the airline.
After the Acars system, the transponder and voice radio contact had all ceased, one device on the plane kept trying to communicate, a satellite transmission device usually used for sending maintenance data. That device kept sending occasional brief signals for several hours after all other contact was lost, Malaysian authorities say; the last signal received from that device indicated that the plane was on or near one of two broad arcs of the earth’s surface. One extends over Indonesia and remote areas of the southern Indian Ocean, the other over the Asian land mass, through western and southwestern China, Kyrgyzstan, Kazakhstan and northern Laos.
One of the pilots keys in a waypoint on a separate screen known as a scratchpad, and after confirming that it has no typographical errors, pushes another button to move it into the sequence already in the flight plan. Normal practice is to orally confirm the waypoint with the other pilot, then push another button to instruct the airplane to go there. With the change in course, the plane would bank at a comfortable angle, around 20 degrees, and make the turn. Passengers would not feel anything unusual.
By Monday, 26 nations were involved in searching those two arcs.
ABC News reported on Sunday that the programmed turn had led investigators to believe that it was being controlled by the pilot or hijackers.
In the southern hemisphere, the Australian Maritime Safety Authority will lead the search through its Rescue Coordination Center, supported by the Australian Defense Force. “Australia is preparing to work with assets from a number of other countries, including surveillance aircraft from New Zealand and the United States,” Prime Minister Tony Abbott said in a statement on Monday.
One American safety expert, John Cox, a former airline union safety official, said that someone taking such pains to divert the plane does not fit the pattern of past cases when pilots intentionally crashed and killed everyone on board.
He said two Orion aircraft from the Royal Australian Air Force that have been involved in the search since March 9 would be “re-tasked to search in the southern Indian Ocean” and that two more would join the search within the next 24 hours.
“There’s an inconsistency in what we’ve seen historically,” he said, comparing the disappearance of Flight 370 with two murder-suicides, of an Egyptair flight off Nantucket Island in 1999 and a SilkAir jet in Indonesia in 1997. In those crashes, he said, the pilot involved simply pushed the nose of the plane down and flew into the water. The authorities searched the homes of the pilots in Kuala Lumpur on Saturday, seizing a flight simulator that one of them had in his home.
The police have been investigating the pilot, co-pilot and other crew members of the missing Malaysia Airlines flight since the day of its disappearance, Malaysia’s Transport Ministry said in a statement on Monday. The statement highlighted growing interest by the law enforcement authorities into whether any of the airline employees might have been complicit in the plane’s disappearance.
In an effort to determine whether the pilot had practiced taking down the plane, the authorities have reassembled the simulator for experts to examine. American investigators would like access to the flight simulator and any other electronic information seized from the pilots, but as of Monday night they had not been given access to those materials.
Adam Dolnik, a professor at the University of Wollongong in Australia who has studied terrorism in Southeast Asia and other parts of the world, said that, judging from the information disclosed so far, there was nothing to suggest any involvement by a terrorist organization. He said, though, that there was the possibility of a “lone wolf” acting at least partly in the name of extremist beliefs.
Meanwhile, as the search for the missing Boeing 777 jet stretched into a 10th day, two of the nations helping in the hunt, Australia and Indonesia, agreed to divide between them a vast area of the southeastern Indian Ocean, with Indonesia focusing on equatorial waters and Australia beginning to search farther south for traces of the aircraft. To the north, China and Kazakhstan checked their radar records and tried to figure out whether the jet could have landed somewhere on their soil.
Mr. Dolnik voiced skepticism that the two Iranian passengers who boarded the plane with stolen passports had played a role in diverting it. “For groups like Al Qaeda, which tried to take airliners down in midcourse flight by a suicide bomber since the mid-1990s, this is their fantasy target, and what they keep going for, but repeatedly they are unable to keep doing it,” he said. “But for a group like this to grow an entire plan — which would have to be quite sophisticated for them to be able to actually get the operational capabilities through the secure perimeter and on board an airplane — and to blow it on something like a stolen passport, it just doesn’t make any sense. What they would do is send operatives who have clean passports, to make sure they actually make it through immigration.”
Mr. Dolnik added: “If you’re a militant jihadist group, why would you ever go for Malaysia Airlines? If you have a predominantly Muslim country, one of the biggest Muslim countries, hitting the national carrier of that country really would be very risky in terms of constituency support or how people are going to view you.”
Malaysia’s Transport Ministry also said that three civil aviation investigators had arrived from France to share expertise gained from the search for Air France Flight 447, which disappeared nearly five years ago off the coast of Brazil. Searchers needed almost two years to find the Air France jet, an Airbus A330, on the floor of the Atlantic Ocean.
Investigators had an advantage in that case, because they had found more than 3,000 pieces of debris and 50 bodies floating in the ocean in the days and weeks immediately after the crash, giving them a rough sense of where the plane had entered the water. By contrast, there are still few clues to where the Malaysia Airlines jetliner finally came down.
The United States search effort is still focused on the Andaman Sea and the Bay of Bengal, in the northeast corner of the Indian Ocean, where the American destroyer Kidd and a surveillance plane are patrolling. In the vast, empty expanses of the southern oceans, however, aircraft can cover a very large area more quickly than ships and ship-based helicopters could.
