BEIRUT: The pilot of the Ethiopian Airlines plane which crashed shortly after takeoff from Beirut in January last year received several cockpit warnings that disaster was imminent, according to an investigative report probing the disaster, made public over the weekend.
The Transport and Public Works Ministry investigation progress report – more than a year after the Jan. 25, 2010, crash that killed all 90 aboard – revealed Saturday how successive signals, designed to alert a pilot to the dangers of stalling or turning too hard, were issued in the moments before the Boeing 737-800 plunged into the sea.
Caretaker Transport and Public Works Minister Ghazi Aridi said that a full analysis into the causes behind flight ET409’s crash would be available before the end of July this year.
“We can completely depend on the reports that will come out before the final report,” Aridi told reporters at Rafik Hariri International Airport. “Our work is going in a good direction.”
The Ethiopian Airlines plane crashed into the Mediterranean less than four minutes after takeoff, after performing two maneuvers ordered by Beirut’s Air Traffic Control team. Data contained in flight recorders retrieved from the crash site show how the aircraft turned slightly immediately after leaving runway 21, before being instructed to bank reasonably hard to its left. It was during this move that the plane got into trouble, plunging 8,000 feet (2,432 meters) before disappearing from radar screens.
The cockpit of a Boeing 737-800 has several ways of communicating to the pilot that a plane is in danger. The “stick shaker” – a vibrating device housed within the central controls – warns that a plane is in danger of stalling; a “Bank Warning” shows when too steep a turn is being attempted; an over-speed clacker warns against performing a tricky maneuver at high speed, which risks structural damage to an aircraft.
According the report, ET409 pilot Habtamu Benti received all three alerts – including 10 “Bank Warnings” and two “stick shakers” before his plane fell from the sky.
Aridi himself apportioned blame on Ethiopian Airlines’ flight crew, claiming in the days following the crash that Benti had performed “a fast and strange turn,” before the crash.
The report stressed that flight investigations, under international aviation treaties, are “not to access individual or collective responsibility” in any crash.
“The sole objective of this investigation is to establish the cause[s] of the accident, draw lessons from what happened and come with appropriate recommendations that may help to prevent future accidents,” it said.
Possible contributing factors have either been explored or dismissed; logs taken before ET409’s takeoff showed no abnormalities, the report said.
“The aircraft weight and balance record was reviewed and no deficiencies or anomalies were noted,” it said. “No defect or deferred maintenance item was reported on the technical log after the arrival and before departure of the plane from Beirut.”
Weather conditions at the time have been factored into the crash probe.
“The accident occurred at night in dark lighting conditions with reported isolated cumulonimbus and thunderstorms in the area,” the report said. Cloud cover at half-past midnight on Jan. 25 began at 2,000 feet, possibly obscuring the pilot’s view or contributing to spatial disorientation – a known factor in previous crashes.
Benti, while a greatly experienced flyer, had only 188 hours of previous flight on the model of aircraft which crashed. Given the nature of modern civilian aviation, where autopilots are often engaged seconds after takeoff, Benti’s paucity of 737-800 experience is likely to be probed. In the pilot’s last proficiency check, three months before the disaster, Benti rated as “satisfactory”: the lowest score which would allow him to continue flying.
The report indicated that eyewitness reports – some of which suggested the aircraft entered the sea off Naameh in flames – were still to be analyzed.
“No evidence of fire has been brought up,” it added.
“All components appeared clean except for some black soot traces found around the APU which will be addressed and analyzed.
“At this stage of the investigation additional information is being verified for consistency with recorded data and wreckage examination findings prior to use in the investigation,” the report said. “This information includes various documents, testimonies and interviews conducted since the accident happened.”
Aridi announced he knew the causes of the crash, but was waiting for an agreement between the Lebanese Civil Aviation Authority, Ethiopian Airlines and Boeing to be finalized before releasing the ministry’s final report.