Investigators locate Ethiopian air crash recorders
Search teams are working to recover the flight data and cockpit voice recorders from the Ethiopian Airlines Boeing 737-800 that crashed shortly after takeoff at Beirut’s Rafik Hariri International Airport during a raging storm last Monday.
Automated signals from the devices have already helped searchers to identify the exact location of the recorders in water 1300 metres deep, about 10 km west of Beirut Airport, but it has not yet been confirmed whether they are still attached to the aircraft fuselage.
The aircraft was bound for Addis Ababa, the Ethiopian capital, and all 90 passengers and crew are presumed dead, with 14 bodies and other remains already recovered.
On modern aircraft such as the B737-800, the “black box” recorders (which are usually coloured luminous orange to assist recovery) carry a mass of digitised data to aid investigators. The cockpit voice recorder stores all cockpit conversations, air traffic control (ATC) communications, and audible automated voice or electronic warnings of abnormalities. The separate flight data recorder retains comprehensive data including the aircraft’s actual three-dimensional flight path, speeds, engine power settings, flap configurations, control inputs, systems functionality, autopilot status, and other data from the aircraft’s flight management computers.
Modern computer analysis systems can be used to analyse the data and even to produce a realistic three-dimensional image of the entire flight, along with all indications from the instrument panel.
The recorders’ homing signals suggest a strong likelihood that the crash-resistant recorders, which are usually sited in or near the aircraft’s tail, remain sufficiently undamaged to have preserved all the stored data.
Recovered bodies are also examined for cause of death, possible impact damage, evidence of damage by explosives, smoke inhalation and other conditions that may be relevant to the investigation. Reports say there were 30 Ethiopian nationals on board, including the seven crew members, and 54 Lebanese, most of them from southern Lebanon.
Media reports however say that sabotage has already been ruled out.
Investigators will be analysing conflicting reports on the aircraft’s flight path, one of which suggests that the crew turned in the opposite direction from the flight path for which it was cleared by ATC.
The international search operation now comprises units of the Lebanese navy, the United Nations Interim Force in Lebanon (UNIFIL), a civilian salvage vessel from Cyprus and US Navy destroyer USS Ramage, which has advanced sonar equipment.
