Air Algérie Flight 6289

Air Algérie Flight 6289

An Air Algérie Boeing 737-200 similar to the aircraft involved in the accident.
Accident summary
Date 6 March 2003
Summary Engine failure on take-off (EFTO)
Site Tamanrasset, Tamanrasset Province, Algeria
Passengers 97
Crew 6
Injuries (non-fatal) 1
Fatalities 102
Survivors 1
Aircraft type Boeing 737-200
Operator Air Algérie
Registration 7T-VEZ
Flight origin Tamanrasset Airport, Tamanrasset
Destination Noumérat – Moufdi Zakaria Airport, Ghardaia

Air Algérie Flight 6289, was a scheduled domestic passenger flight, operated with a Boeing 737-200 which was departing from the southern Algerian city of Tamanrasset for Ghardaia and Algiers. On 6 March 2003, the Boeing 737-200 stalled and crashed near the runway, killing all but one of the 102 people on board.

Witnesses recalled that one of its engines exploded and caught fire just seconds after take off. The landing gear was still extended when this happened. It then rose sharply and stalled.

The final report concluded that the cause of the crash was due to engine failure on take-off, an incident where a plane loses one of its engine shortly after taking-off. This was aggravated by the Captain's decision to take over control without understanding the situation and subsequent miscommunication between the Captain and the First Officer.

The accident was the deadliest plane crash in Algeria's aviation history. At the time, it was Air Algerie's deadliest plane crash. It was surpassed 11 years later by Air Algerie Flight 5017, a McDonnel Douglas MD-83 which crashed in Mali killing all 116 people on board.

Events of the crash

On Thursday 6 March 2003, the Boeing 737 registered 7T-VEZ, operated by Air Algérie, was taking off from Tamanrasset to undertake, with a three-hour delay, scheduled flight DAH 6289 to Ghardaïa and Algiers. Six crew members (two flight crew and four cabin crew) and 97 passengers were on board. The co-pilot was pilot flying. No technical exemptions or deferred maintenance items applied to the airplane; on departure from Algiers it had been subject to routine maintenance for a minor technical problem, a hydraulic pump having been changed in the circuit B landing gear bay.

The speeds decided on by the crew were V1 = 144 kt, VR = 146 kt, V2 = 150 kt. The EPR displayed was 2.18, that is to say nominal maximum thrust on take-off.

The Boeing 737 then took off. About five seconds after the airplane left the ground, at the moment when gear retraction was requested, a sharp thumping noise was recorded on the CVR. The airplane’s heading veered to the left, followed by a track correction. The Captain announced that he was taking over the controls. A short time later, the co-pilot told the control tower “we have a small problem”. The airplane continued to climb and reached a recorded height of about 400 ft.

The speed dropped progressively from 160 kt during airplane lift-off to stall speed at the end of the recording. In fact, about ten seconds before, the noise of the stick shaker is heard on the CVR (which usually indicates that the airplane is 7% from its stall speed). The “Don’t Sink” aural warning, which normally indicates a loss of altitude during take-off when the airplane is below nine hundred feet, appeared about six seconds before the end of the recording.

The airplane, with landing gear extended, struck the ground on its right side. A severe fire broke out immediately. The airplane slid along, losing various parts, struck and knocked over the airport perimeter fence then crossed a road before coming to a halt in flames. An alert was immediately sounded by the control tower.

All but one of the 97 passengers and all of the six crew members perished, a total of 102 people. The only survivor of the accident was 28-year-old Youcef Djillali.[1]

Passengers and Crews

NationalityPassengersCrewTotal
 Algeria78684
 Canada505
 France909
 Germany101
 Japan101
 Netherlands202
 United Kingdom101
Total976103

The Captain was a 48 years old male. He had an experience of 10,760 h 10 min total flying hours, of which 1,087 h 46 min on type as Captain; The Captain also flew on Boeing 767‘s as co-pilot. In this role, he had also flown 31 h 57 min over the previous thirty days.

The Co-Pilot was a 44 years old female. She had an experience of 5,219 h 10 min flying hours of which 1,292 h 42 min on type;

Investigation

Investigators checked the fuel of the plane before taking off and concluded that it was enough and in good condition, along with the maintenance and weight and balance. The weight and balance was counted as 'still in the line', the maintenance note of the aircraft also suggested that the Boeing 737 was in a good condition.

However, witnesses from the ground stated that just after taking off, a strange noise was heard which resembles to be an explosion. They said that one of its engine exploded and caught fire. Among them were an engineers on the ground and one of the controller in the tower. The engineers statement:

"I was on the parking lot and I saw the plane take off on runway 02. Just after the take-off, the plane swerved slightly to the left, then righted itself on the track and at that moment, I noticed that the plane was losing speed and altitude, still with its landing gear down until the moment of the crash, when there was a total explosion.”

The controllers on the tower also backed up the statement, saying:

“DAH 6389 B732 IMMAT: 7T-VEZ asked to be cleared for take off 1402GMT. At 1405 GMT, it was cleared for take off with a temperature of 23°, QNH: 1019.Cleared by ALGER CCR to initial FL280, just after the takeoff from runway 02 (1405) a kind of explosion was heard, the alarm was immediately activated, the pilot said we have a small problem. . . the plane began to fall and crashed near the threshold of runway 20; the emergency plan was immediately activated as planned. 1) Aerodrome rescue services at 1415. 2) Civil services at 1416. 3) Hospital just afterwards. Then the rest of the services mentioned in the emergency plan.”

During this phase, there was a sharp nose-up pitch attitude. The plane was at low altitude and seemed to be losing speed. It then dived with a slight angle to the right and crashed. The landing gear was extended.

Investigators found a part of the plane's engine on the runway and start an examination of the plane's engine.

Examination of the engines

Investigators examine the plane's engine from the wreckage. Both of the airplane's engines and their principal accessories were transported to Brussels (Belgium) to a specialized SNECMA laboratory. There they were completely torn down. The examinations carried out found that the two engines showed no uncontained failures and no indication of any fire. However, the rotating parts of the cold section of both engines showed deformations, significant on the right engine, less so on the left engine. This means that at the moment of impact with the ground, the latter was rotating at low speed, not developing any thrust. The hot section of the left engine also had damaged components, corresponding to those found on the runway. The hot section of the right engine also had some damage. However, the engine was not damaged a foreign object.

An additional check was conducted. The fuel injectors were found in good condition, alongside with the flame tubes with no sign of overheating. The blades also didn't show any metal fatigue. However, cracks on the blades were revealed as the examination continues.

The examinations of the left engine and the debris found on the runway showed that the problem stemmed from the HP part of the turbine. The part backing the LP turbine was consequently destroyed, which accentuated the loss of power and led to a sharp drop in engine rotation speed. The damage to the blades confirmed a slow rate of engine rotation at the moment of impact.

Poor Crew Resource Management examination

Investigators noted the lack of preparedness on the part of the aircrew who worked the flight, and the unsuitability of the rocky ground near the airfield for emergency landings.[2] In any event, the absence of any coordination between the pilots at the moment when tasks were transferred meant the Captain had to manage an emergency situation, which he had not had time to analyze completely. For the same reasons, he did not rely on the co-pilot, whom he simply asked on several occasions to let go (of the controls). He likely encountered some problems in taking over control, given that he repeated the terms “let go” and “take your hand off”, this continuing until the end of the recording. The co-pilot appears to have carried out the Captain’s orders by reading back in the affirmative and indicating her willingness to act (proposal to retract the gear, radio message to the tower with the hand mike) though without being sure of the role she was supposed to play. This may, for example, have resulted in her placing her hands on the control column at the time of the stall warning alarms, which would explain the repeated requests from the Captain. She was thus not fully carrying out her role as PNF and did not monitor or at least call out the speeds as they were decreasing. The co-pilot’s offer to retract the gear was probably not even noticed by the Captain, due to his sudden excess workload.

According to the airline’s procedures, the initial climb on one engine should be performed with the gear retracted, maintaining safety speed at V2 until the safety altitude. However, the landing gear was never retracted. With the conditions on the day of the accident, the calculations and simulations performed show that it was difficult to maintain a positive rate of climb. Since the altitude was continuing to increase at the same rate, it was logical that there should be a progressive drop in speed.

The Captain took over the flight controls in a critical situation while he was out of the loop with regard to flying. This probably led him to focus on a pitch attitude that was incompatible with one failed engine. His decision to take over the controls made it impossible for him to develop and supervise a strategy to adopt for the conduct of the flight.

The left engine failure coincided with the co-pilot’s request to retract the landing gear and disrupted that action. The co-pilot mentioned retracting the gear again but, at that moment, the task-sharing had been reversed. It was up to the Captain to ask for gear retraction. In the end, the gear remained extended until the impact.

The airplane’s aerodynamic performance subsequently deteriorated rapidly, especially as a result of the non-retraction of the gear, which added to the effect of maintaining a high pitch attitude. In addition, it should be emphasized that the high altitude of the aerodrome and the high temperature on the day, as well as a takeoff weight close to the maximum also contributed to limiting the airplane’s performance. During the initial climb, the high pitch attitude and the yaw induced by the failure of the left engine (which had the effect of increasing the drag at a critical moment), added to the factors previously mentioned.

The high pitch attitude and the loss of speed put the airplane in a stall situation. About fourteen seconds after the noise and the “gear up” callout, the stick shaker began to operate intermittently, then continuously, until the end of the recording. The “don’t sink” aural warning told the crew that the airplane was dropping. The pitch attitude was apparently maintained until impact with the ground, as examination of the site showed. On the wreckage, the horizontal stabilizer trim was found in the position for a normal takeoff, which tends to support this hypothesis.

Conclusion

The final report was published with the following: 

"The accident was caused by the loss of an engine during a critical phase of flight, the non-retraction of the landing gear after the engine failure, and the Captain, the PNF, taking over control of the airplane before having clearly identified the problem."

The following factors probably contributed to the accident:

See also

References

  1. ↑ Tamanrasset : 102 mortsdont 6 Français." (Archive) Le Nouvel Observateur. 11 March 2003. Retrieved on 31 December 2013.
  2. ↑ "ASN Aircraft accident Boeing 737-2T4 7T-VEZ Tamanrasset Airport (TMR)". Aviation Safety Network. Flight Safety Foundation. Retrieved 20 July 2013.

External links

Coordinates: 22°47′N 5°31′E / 22.783°N 5.517°E / 22.783; 5.517

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