Thursday, August 21, 2008


(Courtesy: The internet)
Brief Description

A MD-82 aircraft operated by Spanair from Madrid-Barajas (MAD) to Gran Canaria (LPA) was destroyed when it crashed on take-off at MAD, killing 154 occupants, including all six crew members, and seriously injuring 18. The estimated departure time of the flight was 13:00. The aircraft was authorized to start-up at 13:06:15. It taxied to runway 36L. The flaps were extended to 11° for take-off. The aircraft was cleared for takeoff at 13:24:57. The crew informed the ATC at 13:26:27 that they had a problem and that they had to exit the runway. At 13:33:12, they communicated that they were returning to the stand.

The crew had detected an overheating Ram Air Temperature (RAT) probe. The aircraft returned to the apron. The maintenance confirmed the malfunction described, checked the RAT probe heating section of the Minimum Equipment List (MEL) and opened the electrical circuit breaker that connected the heating element. Once complete, it was proposed and accepted that the aircraft be dispatched. The aircraft was topped off with 1080 liters of kerosene and at 14:08:01 it was cleared for engine start-up and to taxi to runway 36L for takeoff.

The crew continued with the tasks to prepare the airplane for the flight. The conversations on the cockpit voice recorder revealed certain expressions corresponding to the before engine start checklists, the normal start list, the after start checklist and the taxi checklist. On the final taxi segment the crew concluded its checks with the takeoff imminent checklist. At 14:23:14, the aircraft was cleared for take-off from runway 36L. Along with the clearance, the control tower informed the aircraft that the wind was from 210° at 5 knots.

At 14:23:19, the crew released the brakes for takeoff. Engine power had been increased a few seconds earlier and at 14:23:28 its value was 1.4 EPR. Power continued to increase to a maximum value of 1.95 EPR during the aircraft’s ground run. The CVR recording shows the crew calling out "V1" at 14:24:06, at which time the DFDR recorded a value of 147 knots for calibrated airspeed (CAS), and "rotate" at 14:24:08, at a recorded CAS of 154 knots. The DFDR recorded the signal change from ground mode to air mode from the nose gear strut ground sensor. The stall warning stick shaker was activated at 14:24:14 and on three occasions the stall horn and synthetic voice sounded in the cockpit: "[horn] stall, [horn] stall, [horn] stall". Impact with the ground took place at 14:24:23.

During the entire takeoff run until the end of the CVR recording, no noises were recorded involving the takeoff warning system (TOWS) advising of an inadequate takeoff configuration. During the entire period from engine start-up while at parking stand R11 to the end of the DFDR recording, the values for the two flap position sensors situated on the wings were 0°.
The length of the takeoff run was approximately 1950 m. Once airborne, the aircraft rose to an altitude of 40 feet above the ground before it descended and impacted the ground. During its trajectory in the air, the aircraft took on a slight left roll attitude. The crew momentarily retarded the engine throttles, increased the pitch angle and did not correct for the left roll angle. The left roll was followed by a fast 20° roll to the right, another slight roll to the left and another abrupt roll to the right of 32°. The maximum pitch angle recorded during this process was 18°.

The aircraft’s tailcone was the first part to impact the ground, almost simultaneously with the right wing tip and the right engine cowlings. The marks from these impacts were found on the right side of the runway strip as seen from the direction of the takeoff, at a distance of 60 m, measured perpendicular to the runway centerline, and 3207.5 m away from the threshold, measured in the direction of the runway. The aircraft then traveled across the ground an additional 448 m until it reached the side of the runway strip, tracing out an almost linear path at a 16° angle with the runway. It lost contact with the ground after reaching an embankment/drop-off beyond the strip, with the marks resuming 150 m away, on the airport perimeter road, whose elevation is 5.50 m lower than the runway strip. The aircraft continued moving along this irregular terrain until it reached the bed of the Vega stream, by which point the main structure was already in an advanced state of disintegration. It is here that it caught on fire. The distance from the initial impact site on the ground to the farthest point where the wreckage was found was 1093m.

No comments: