Spanair Flight 5022

Investigation

The accident was investigated by the Civil Aviation Accident and Incident Investigation Commission (CIAIAC). Representatives from the US National Transportation Safety Board, the aircraft manufacturer Boeing (as successor to McDonnell Douglas, the original aircraft manufacturer), and the engine manufacturer Pratt and Whitney supported the investigation.

A preliminary report on the accident was released by CIAIAC on 6 October 2008. Information extracted from the flight data recorder showed that the aircraft had taken off with flaps at 0°, and that the alarm for that abnormal takeoff configuration had not sounded. The report hinted at no other cause of the accident. Both the engines and thrust reversers were excluded as causes of the accident.

On 17 August 2009, CIAIAC released an interim report on the incident. The interim report confirmed the preliminary report's findings and added further evidence that the take off had been carried out with the flaps and slats retracted. The cockpit recordings revealed that the pilots omitted the "set and check the flap/slat lever and lights" item in the After Start checklist. In the Takeoff Imminent verification checklist the copilot had simply repeated the correct flap and slat position values without actually checking them, as shown by the physical evidence. All three safety barriers provided to avoid the takeoff in an inappropriate configuration were defeated: the configuration checklist, the confirm and verify checklist, and the Take-off Warning System (TOWS). The report also made safety recommendations intended to prevent accidents like this from happening again.

CIAIAC published a further progress note in August 2010, and its final report in July 2011.

Final report

The CIAIAC published its final report into the accident on 26 July 2011.

It determined that the cause of the accident was:

The crew lost control of the aircraft as a result of a stall immediately after takeoff, which was caused by an incorrect configuration for take-off (i.e. not deploying the flaps and slats, following a series of errors and omissions), coupled with the absence of any warning of the incorrect configuration.

The crew did not recognise the indications of stall, and did not correct the situation after takeoff, and – by momentarily retarding the engine power and increasing the pitch angle – brought the aircraft closer to a stall condition.

The crew did not detect the configuration error because they did not properly use the checklists to select and check the position of the flaps and slats during flight preparation, specifically:

they failed to select the flaps/slats lever during the corresponding step in the "After Start" checklist;

they did not cross-check the position of the lever and the state of the flaps/slats indicator lights during the "After Start" checklist;

they omitted the flaps/slats check on the 'Take Off Briefing' (taxi) checklist;

no visual inspection of the flaps and slats was carried out in execution of the "Final Items" step of the "Take Off Imminent" checklist.

The CIAIAC determined the following contributory factors:

The absence of any warning of the incorrect take-off configuration because the TOWS did not work. It was not possible to determine conclusively the cause of this failure.

Inadequate crew resource management (CRM), which did not prevent the deviation from procedures and omissions in flight preparation.

In addition, the CIAIAC's analysis found that flight may have been possible despite the flaps and slats being in the retracted position, however it would have required a lower pitch angle and stable wings. They concluded that the best way for the pilots to have recovered from the stall would have been to simply extend the flaps.