Ethiopian Airlines Flight 409 was a scheduled international flight between Beirut-Rafic Hariri International Airport (BRHIA) and Addis Ababa Bole International Airport (ADD) in Ethiopia. On January 25, 2010, the Boeing 737-8AS operating the flight crashed into the Mediterranean Sea shortly after takeoff from Beirut, resulting in the loss of all 90 persons on board.
The aircraft involved was a Boeing 737-8AS(WL), registration ET-ANB, s/n 29935. It first flew on 18 January 2002, and was delivered new to Ryanair on 4 February 2002 as EI-CSW. In command was 44-year-old Captain Habtamu Benti Negasa, who had been with Ethiopian Airlines since 1989. He was one of the airline's most experienced pilots, having logged 10,233 flight hours, including 2,488 hours on the Boeing 737. The first officer was 23-year-old Aluna Tamerat Beyene.
The accident was dramatized in the twelfth series of the Canadian documentary Mayday (also known as Air Emergency or Air Crash Investigation). It is titled "Heading to Disaster".
Heading to disaster: Ethiopian Airlines flight 409
Sequence of Events
The Boeing 737 took off from runway 21 at Beirut-Rafic Hariri International Airport in stormy weather, with 82 passengers and eight crew members on board. The METAR data indicated wind speeds of 8 knots (15 km/h; 9 mph) from varying directions, with thunderstorms in the vicinity of the airport. The flight departed at night on an instrument flight plan. Low clouds, isolated cumulonimbus (CB) and thunderstorms were reported in the area.
The flight was initially cleared by ATC on a LATEB 1 D departure then the clearance was changed before take-off to an “immediate right turn direct Chekka”. After take-off ATC (Tower) instructed ET 409 to turn right on a heading of 315°. ET 409 acknowledged and heading 315° was selected on the Mode Control Panel (MCP). As the aircraft was on a right turn, Control suggested to ET 409 to follow heading 270° “due to weather”. However, ET 409 continued right turn beyond the selected heading of 315° and Control immediately instructed them to “turn left now heading 270°”.
Read also: Navigating Ethiopian Airlines
ET 409 acknowledged, the crew selected 270° on the MCP and initiated a left turn. ET 409 continued the left turn beyond the instructed/selected heading of 270° despite several calls from ATC to turn right heading 270° and acknowledgment from the crew. ET 409 reached a southerly track before sharply turning left until it disappeared from the radar screen and crashed into the sea 4‟ 59” after the initiation of the take-off roll (4‟17” in the air). The aircraft impacted the water surface around 5 NM South West of BRHIA and all occupants were fatally injured. Search and Rescue (S&R) operations were immediately initiated.
The aircraft climbed erratically to 9,000 feet (2,700 m), stalled and entered a spiral dive to the left. Radar contact was lost a few seconds before it crashed into the Mediterranean Sea at 02:41 local time (UTC +2/EET), four or five minutes after take off.
Search and Recovery Efforts
In response to a request from the Lebanese government, the U.S. military sent the guided missile destroyer USS Ramage, a Navy Lockheed P-3 Orion aircraft, and the salvage ship USNS Grapple. The French Navy sent a Breguet Atlantic reconnaissance aircraft. UNIFIL sent three ships (among them the German minesweeper tender Mosel and the Turkish corvette Bozcaada) and two helicopters to the scene.
On 7 February, Lebanese Army divers recovered the plane's flight data recorder (DFDR) and cockpit voice recorder (CVR). The CVR was missing a memory storage unit when found. All the deceased were recovered from the sea by 23 February. The recovered bodies were sent to the Rafik Hariri University Hospital in Beirut for DNA testing and identification.
Read also: Ethiopia Pilot Requirements
Investigation Findings
The DFDR and CVR were retrieved from the sea bed and were read, as per the Lebanese Government decision, at the BEA facility at Le Bourget, France. The recorders data revealed that ET 409 encountered during flight two stick shakers for a period of 27” and 26”. They also recorded 11 “Bank Angle” aural warnings at different times during the flight and an over-speed clacker towards the end of the flight.
The maximum recorded AOA was 32°, maximum recorded bank angle was 118° left, maximum recorded speed was 407.5 knots, maximum recorded G load was 4.76 and maximum recorded nose down pitch value 63.1°. The DFDR recording stopped at 00:41:28 with the aircraft at 1291‟. The last radar screen recording was at 00:41:28 with the aircraft at 1300‟.
The report stated that eyewitnesses, including an air traffic controller, and a crew flying in the vicinity of Flight 409, had reported seeing an "orange light", "an orange explosion", or "a ball of fire" which matched "the time and calculated location of the accident". On the wreckage "a black soot near the APU exhaust" was found with "some wrinkle on the metal". A laboratory examination by the NTSB "confirmed that the black soot was not related to excessive heat or fire", because "Zinc chromate primer paint changes color when exposed to heat" and "there was no change in the color of the paint on the primer side".
Probable Causes
The investigation identified the following probable causes:
- The flight crew's mismanagement of the aircraft's speed, altitude, headings and attitude through inconsistent flight control inputs resulting in a loss of control.
- The flight crew failure to abide by CRM principles of mutual support and calling deviations hindered any timely intervention and correction.
Contributing Factors
The following contributing factors were identified:
Read also: The Hijacking of Ethiopian Airlines Flight 508
- The manipulation of the flight controls by the flight crew in an ineffective manner resulted in the aircraft undesired behavior and increased the level of stress of the pilots.
- The aircraft being out of trim for most of the flight directly increased the workload on the pilot and made his control of the aircraft more demanding.
- The prevailing weather conditions at night most probably resulted in spatial disorientation to the flight crew and lead to loss of situational awareness.
- The relative inexperience of the Flight Crew on type combined with their unfamiliarity with the airport contributed, most likely, to increase the Flight Crew workload and stress.
- The consecutive flying (188 hours in 51 days) on a new type with the absolute minimum rest could have likely resulted in a chronic fatigue affecting the captain's performance.
- The heavy meal discussed by the crew prior to take-off has affected their quality of sleep prior to that flight.
- The aircraft 11 bank angle aural warnings, 2 stalls and final spiral dive contributed in the increase of the crew workload and stress level.
- Symptoms similar to those of a subtle incapacitation have been identified and could have resulted from and/or explain most of the causes mentioned above.
Ethiopian Airlines' Response
Ethiopian Airlines stated that it "strongly refutes" the report and it "was biased, lacking evidence, incomplete and did not present the full account of the accident". The airline released a press statement on the day the investigation report was presented. Ethiopian airlines dismissed the report saying its crew was well-rested and it adhered to international standards on hours of work and rest.
Table of Key Data
| Parameter | Value |
|---|---|
| Maximum Recorded Angle of Attack (AOA) | 32° |
| Maximum Recorded Bank Angle | 118° Left |
| Maximum Recorded Speed | 407.5 Knots |
| Maximum Recorded G Load | 4.76 |
| Maximum Recorded Nose Down Pitch Value | 63.1° |
