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Unverified Data Points to Rapid Loss of Control Aboard EgyptAir Jet Data Points to Rapid Loss of Control Aboard EgyptAir Jet
(about 3 hours later)
CAIRO — In the minutes before an EgyptAir flight from Paris to Cairo crashed into the Mediterranean Sea, killing all 66 people on board, there were rapid and escalating failures in the plane’s flight control system, according to sensor data transmitted by the aircraft to operators on the ground that was published Friday by a respected aviation journal. CAIRO — A piece of luggage adrift in the Mediterranean Sea. Floating nearby, a passenger seat from a plane. Scraps of metal, scattered personal belongings and, finally, the grim discovery of human remains.
As aviation officials sorted through the data, which was posted online by The Aviation Herald, Egyptian naval crews scoured the sea in the area where the airplane was last recorded on radar, and found bits of wreckage bobbing in the waves, incuding an airplane seat, luggage and human remains. As the investigation continued Friday into what caused an EgyptAir flight from Paris to Cairo to suddenly and violently plunge from the sky, the discovery of the debris allowed search crews to home in on the location of the crash — an area about 180 miles north of Alexandria, Egypt — even as its cause remained a mystery and the subject of intense speculation.
Even after the publication of the technical data, which could not be independently confirmed, and the recovery of parts of the plane in the water, the cause of the crash remained a mystery and the subject of intense speculation. Data that was transmitted from the aircraft to operators on the ground, published Friday by a respected aviation journal, revealed a rapid loss of control, with alarms and computer-system failures in the seconds before the plane was lost from radar.
No bulk wreckage has yet been spotted, and the parts of the aircraft most likely to provide clues for investigators are also the ones most likely to have quickly sunk to the sea floor. The transmissions are evidence of a catastrophic failure, but do not answer the crucial question: What caused it? Why would a plane with a good safety record and experienced pilots fall from the sky on a clear spring night?
No bulk wreckage has been found, and the parts of the aircraft most likely to provide clues for investigators — including the voice and data recorders — are also the ones most likely to quickly sink to the seafloor.
An Egyptian official has said that investigators consider terrorism to be one possible cause of the disaster, but no terrorist group has claimed responsibility. Officials cautioned that there was no direct evidence to suggest a bomb aboard the plane, or any other deliberate act of sabotage.An Egyptian official has said that investigators consider terrorism to be one possible cause of the disaster, but no terrorist group has claimed responsibility. Officials cautioned that there was no direct evidence to suggest a bomb aboard the plane, or any other deliberate act of sabotage.
EgyptAir Flight 804, an Airbus A320 jetliner, disappeared from radar screens early Thursday morning as it was flying to Cairo from Paris. Before it vanished, the jet apparently plunged from cruising altitude while swerving violently and then flying in a circle, the Greek defense minister, Panos Kammenos, said at a news conference on Thursday. The plane, a twin-engine Airbus A320 jet, went down Thursday while flying through a cloudless night sky en route to Cairo from Paris.
On Friday, Mr. Kammenos said that debris had been found floating within the 40-square-mile search area. He told reporters in Athens that the Egyptian military had confirmed “the discovery of a body part, a seat and baggage just south of where the aircraft signal was lost.” The Hellenic Civil Aviation Authority provided what a spokesman called a definitive timeline on the disaster. The agency reported that the flight was proceeding normally at 1:48 a.m. Cairo time on Thursday, when Greek traffic controllers last spoke with the pilot, who seemed in good spirits.
The Egyptian Army spokesman, Brig. Gen. Mohammed Samir, said in an interview on Friday that “there is no doubt” that the debris came from the EgyptAir plane.
The discovery of the remains and wreckage appeared to dash any lingering hopes of finding survivors. Among the dozen or so countries whose citizens were on the flight, Egypt suffered the greatest loss, with 30 people on board. The tragedy added grief to a sense of disbelief over a recent string of disasters, including the Russian airliner that was brought down shortly after it left the Egyptian resort of Sharm el-Sheikh in October, dealing a crippling blow to the country’s tourism.
The Hellenic Civil Aviation Authority has provided what a spokesman called a definitive timeline on the disaster. The agency reported that the flight was proceeding normally at 1:48 a.m. Cairo time on Thursday, when Greek traffic controllers last spoke with the pilot, who seemed in good spirits.
At 2:27 a.m., when the plane was passing from Greek to Egyptian-supervised airspace, the controllers in Athens tried and failed repeatedly to reach the pilots by radio. Even attempts on an emergency frequency failed.At 2:27 a.m., when the plane was passing from Greek to Egyptian-supervised airspace, the controllers in Athens tried and failed repeatedly to reach the pilots by radio. Even attempts on an emergency frequency failed.
At the same time, technical data was being transmitted from the plane automatically through an automatic system aboard the plane called the Aircraft Communications Addressing and Reporting System, or Acars. Modern jetliners use to provide status updates to maintenance and operational centers on the ground. At the same time, technical data was being transmitted from the plane automatically through its Aircraft Communications Addressing and Reporting System, or Acars, which modern jetliners use to provide status updates to maintenance and operational centers on the ground.
Representatives of Airbus and the Federal Aviation Administration said they could not confirm the authenticity of the technical signals. Dina El-Fouly, a spokeswoman for EgyptAir, declined to comment on the apparently leaked data. “We cannot say anything, because we have already launched a committee to investigate the crash,” she said. “It hasn’t told us anything until now.” Representatives of Airbus and the Federal Aviation Administration said they could not confirm the authenticity of the technical signals. Dina El-Fouly, a spokeswoman for EgyptAir, declined to comment on the apparently leaked data.
The data, first reported on AVHerald.com, is written tersely in abbreviations and codes. Robert W. Mann, a former commercial airline pilot and an industry analyst, said the jargon in the messages told a compelling, albeit incomplete, story. “We cannot say anything, because we have already launched a committee to investigate the crash,” she said. “It hasn’t told us anything until now.”
At 2:26 a.m., a message indicated that the right cockpit window has been opened. This could have been done to vent smoke, Mr. Mann said, or something else could have cause the breach. The data, first reported on AVHerald.com, is written tersely in abbreviations and codes. Robert W. Mann, a former commercial airline pilot and an industry analyst, said the jargon in the messages told a compelling, although incomplete, story.
At 2:26 a.m., a message indicated that the right cockpit window had been opened. This could have been done to vent smoke, Mr. Mann said, or something else could have caused the breach.
Over the next two minutes, there were two smoke indications, one in a bathroom and another in the avionics bay, the part of the plane where much of its electronic equipment is housed.Over the next two minutes, there were two smoke indications, one in a bathroom and another in the avionics bay, the part of the plane where much of its electronic equipment is housed.
Mr. Mann cautioned that these messages did not necessarily mean that there was a fire. The messages could also have been triggered by rapid decompression of the aircraft, which can produce condensation that the plane’s sensors could mistake for smoke. Mr. Mann cautioned that these messages did not necessarily mean that there was a fire. The messages could also have been prompted by rapid decompression of the aircraft, which can produce condensation that the plane’s sensors could mistake for smoke.
Finally at 2:29, there were two more alerts having to do with the plane’s flight control computer systems.Finally at 2:29, there were two more alerts having to do with the plane’s flight control computer systems.
“The last two are troubling,” Mr. Mann said. “You are starting to really see things rapidly degrade.”“The last two are troubling,” Mr. Mann said. “You are starting to really see things rapidly degrade.”
First, there was a problem with the autoflight control computer. The jet would have been flying near its maximum speed and elevation at that time. That is the most efficient way for jetliners to fly, and it is completely safe, Mr. Mann said, but pilots prefer to rely on autopilot systems in those conditions because if they were to ever lose control of the plane, it could be hard to regain. That is why pilots sometimes call those conditions the “coffin corner,” he said. First, there was a problem with the autoflight control computer. The jet would have been flying near its maximum speed and elevation at that time. That is the most efficient way for jetliners to fly, and it is safe, but pilots prefer to rely on autopilot systems in those conditions because if they were to ever lose control of the plane, it could be hard to regain, Mr. Mann said. That is why pilots sometimes call those conditions the “coffin corner.”
The last message had to do with the spoiler elevator controller, which essentially controls the flaps responsible for controlling the pitch and roll of the airplane. A computer controlling the flaps failed as well. The last message had to do with the spoiler elevator controller, which essentially controls the flaps responsible for pitch and roll control. The computer controlling these failed as well.
“It looks to me like you have a progressive flight control system failure,” Mr. Mann said. It appeared to take place over the course of two minutes, which might seem like an eternity on that plane, but is relatively fast. “It looks to me like you have a progressive flight control system failure,” Mr. Mann said. It is over the course of two minutes, which might have seemed like an eternity on that plane, but is relatively fast.
This was also the moment that the plane left Greek airspace, and at 2:29:40 a.m., Greek controllers lost sight of the aircraft on radar. It was just inside Egyptian airspace, about halfway between Crete and Egypt. This is also the moment that the plane left Greek airspace, and at 2:29:40 a.m., Greek controllers lost the aircraft’s trace, just inside Egyptian airspace, about halfway between Crete and Egypt.
“If that is correct, then it has landed on a feature we call the Mediterranean Ridge,” said William B.F. Ryan, a scientist at the Lamont-Doherty Earth Observatory at Columbia University who has studied the Mediterranean Sea floor. Around this time, the plane made a 90-degree turn to the left and then a full circle to the right, dropping precipitously to 15,000 feet from 37,000 and then plunging again to 9,000 feet before it disappeared from radar.
The ridge has been pushed upward by the African plate of the earth’s crust sliding under the Aegean Sea, deforming and crumbling the sea floor, Dr. Ryan said. “You get a complex play of echoes that was nicknamed cobblestone, showing the sea floor is very bumpy,” he said. The crew never gave any indication of a technical problem or other difficulties on board, even during the final, fatal minutes when the plane itself was transmitting data indicating a catastrophic failure.
The water there is about 1.5 miles deep, and picking out wreckage at the bottom from among the bumps, which are perhaps 50 to 100 feet in size, could be somewhat complex, he said. But if the plane’s “black box” flight recorders are sending out ultrasonic locator signals, it should be possible to locate them fairly soon. One former crash investigator said that radar evidence pointing to a series of sharp maneuvers in the moments before radar contact was lost suggested that the plane was almost certainly not under the control of the pilots.
Still, it may take time to organize the search and recovery of the wreckage, using specialized robots, sophisticated sonar and deep-water equipment. Whatever upset the Airbus was so sudden and violent that it could not be compensated for by the plane’s automated safety systems.
“The club of organizations that have the capability to work efficiently at that depth is fairly small,” said David Gallo, a scientist who helped lead the search in 2009 for debris from Air France Flight 447, which crashed in the South Atlantic on a flight to Paris from Rio de Janeiro, killing 228 aboard. It took two years before the black boxes from that flight were finally recovered. “In my mind, this basically opens two axes of possibility: either a sudden technical problem or some kind of illicit or terrorist act,” said the expert, Alain Bouillard, a former chief investigator for the French Bureau of Investigations and Analyses.
Egypt was joined in the sea and air search effort on Friday by teams from Britain, Cyprus, France, Greece and Italy. In addition, French and British investigators and one expert from Airbus, the plane’s manufacturer, joined a team of Egyptian investigators to inspect the airplane parts as they were discovered. Through that painstaking effort, and the hoped-for recovery of the plane’s flight data recorders, they hope to determine whether the crash was caused by an act of terrorism or sabotage, or by mechanical or human failure. Given the limited amount of evidence available so far, experts said it was difficult to say with any certainty what kind of technical failure could have brought the plane down.
President Abdel Fattah el-Sisi of Egypt expressed his condolences on Friday to the families of victims. Mr. Sisi, “with utmost sadness and regret, mourns the victims on board the EgyptAir flight who were killed,” his office said in a statement. One possibility, Mr. Bouillard said, might be a malfunction in the plane’s cabin pressurization systems that could have caused the fuselage to rupture. At high altitude, such a rupture could be potentially catastrophic if the crew was unable to initiate a controlled descent to a lower altitude and make an emergency landing.
As the debris was found, more details began to emerge about the passengers on the flight. The British news media reported that the only Briton on the plane was Richard Osman, 40, a father of two whose young daughter was born less than a month ago. If the inquiry fails to uncover strong evidence of a technical problem, experts said the possibility of a more sinister chain of events would most likely take prominence. But given the circumstances of this accident, particularly in the absence of a claim of responsibility by a terrorist group or intelligence pointing to a perpetrator, it could take months to prove with any certainty that it was a terrorist act.
Alastair Osman told ITV News that his brother, described as a workaholic and fitness enthusiast, grew up in Wales and worked in the gold-mining industry. The son of an Egyptian doctor, he lived with his French-born wife in Jersey, an island in the English Channel. An initial review of the passengers aboard against American terrorist watch lists have found no matches, according to Representative Adam B. Schiff of California, the senior Democrat on the House Intelligence Committee, who has received several briefings on the investigation.
Osman Abu Laban, a Lebanese film director who lives in Egypt, lost four members of his extended family in the crash. In a post on his Facebook page, Mr. Abu Laban announced funeral prayers on Friday afternoon at a Cairo mosque for his aunt and uncle, their son and the son’s wife. The Islamic State, considered the most likely group behind the attack, is normally quick to announce its role, as it did last fall after the crash of a Russian flight over Egypt’s Sinai Desert.
“Oh God, be merciful to them, forgive them and make their abode the highest heaven,” Mr. Abu Laban wrote. “Its important to note that attribution in the theater of terrorism is crucial,” said Michael S. Smith II, a managing partner of Kronos Advisory, a firm specializing in terrorism research.
What may be most valuable to investigators — and perhaps far more difficult to recover — is material that would have quickly sunk to the seafloor.
If that debris is scattered over a wide area, and the pieces are relatively small, it would suggest that the plane broke up in the air — supporting the theory of an onboard explosion. However, if the debris field is concentrated in a relatively small area, that would indicate that the aircraft hit the surface of the water largely intact.
The plane’s two flight data recorders, or “black boxes,” if they can be recovered, would also provide important clues.
The shock wave of an onboard explosion, for example, may have been captured by the microphones of the cockpit voice recorder, experts said; such a blast would also instantly disable the flight data recorder. In the event of a technical failure, Mr. Bouillard said, the data recorder — which tracks information including the plane’s position, speed, altitude and direction — would normally continue to function until the moment of impact.
Officials could also not rule out that one of the pilots intentionally brought down the plane.
The flight track of the Airbus on Thursday indicated that it crashed halfway between Crete and Egypt, which could mean it landed on what scientists refer to as the Mediterranean Ridge.
The ridge has been pushed upward by the African plate of the earth’s crust sliding under the Aegean Sea, deforming and crumbling the seafloor, said William B.F. Ryan, a scientist at the Lamont-Doherty Earth Observatory at Columbia University who has studied the Mediterranean seafloor.
The water there is about 1.5 miles deep, and picking out wreckage at the bottom from among the bumps, which are perhaps 50 to 100 feet in size, could be complex, he said.
If the plane crashed farther to the south, the wreckage would lie on a smoother plain at a depth between 1.7 and 2 miles, Dr. Ryan said. In that case, the search would go faster — and the much-desired answer to what caused the crash could come quicker.