Spanish investigators have disclosed that the crew of the crashed Spanair Boeing MD-82 ran through normal checklists before the fatal departure, but have yet to explain the reasons for the apparent failure to extend the flaps.
In its first official release of detailed information about the 20 August accident at Madrid, the Comision de Investigacion de Accidentes e Incidentes de Aviacion Civil (CIAIAC) has given further evidence that the aircraft was not configured correctly for take-off.
It states that two control cylinders for the slats were recovered from the wreckage, and other related components, all of which were fire-damaged but "presented evidence consistent with a retracted-slat condition".
The investigators have also retrieved five flap actuators - three from the right wing and two from the left - although four could extend and retract freely because they had lost hydraulic pressure. The fifth was badly damaged by fire.
Information leaked from draft preliminary findings had already pointed to the aircraft's flaps not having been deployed as the MD-82 made a second attempt at departure.
Its previous attempt - during which the flaps had been set to 11° - had been aborted when the jet returned to stand, in order to resolve a technical problem with the ram-air temperature probe.
As the crew prepared the aircraft to taxi out again, says the official CIAIAC statement of 9 October, the cockpit-voice recorder picked up expressions associated with before-start checklists, normal start-up procedures, the after-start checklist and taxi checklist, and the pre-take-off checklist.
But the CIAIAC has not given details of any specific checks, or responses, made by the pilots regarding the aircraft's flap and slat configuration.
It confirms earlier information, however, that no configuration warning sounded in the cockpit during the take-off sequence, and that flight-data recorder registered zero flap deployment. The aircraft failed to climb out of the airport and crashed, killing 154 of the 172 on board.