Technology

Voice recorder of crashed Air Algerie jet ;unusable; due to malf

USPA News - The cockpit voice recorder from the Air Algerie passenger plane that crashed in northern Mali last month is "unusable" due to a recorder malfunction unrelated to the accident, investigators said Thursday as they published their initial findings into the crash that killed 116 people. A group of investigators from countries involved in the accident have so far been able to extract some of the flight parameters from the aircraft`s Flight Data Recorder (FDR), which allowed them to create a first image of the plane`s flight path.
Other parameters have yet to be analyzed, and additional calculations must be performed to further define the events of the flight. However, in a major blow to the investigation, investigators have been unable to retrieve any usable information from the magnetic tape in the aircraft`s cockpit voice recorder. "Unfortunately, the recordings that it contains are unusable, apparently due to a recorder malfunction, which is not linked to the damage from the accident," the French Civil Aviation Safety Investigation Authority (BEA) said. Investigators said they were still working to find other ways to extract information from the magnetic tape, but they warned it is not possible to predict whether they will be successful. "The absence of usable data from the CVR at present underlines the need to collect all data on communications that the crew may have had with organizations on the ground or with other aircraft," BEA added. But although investigators have been unable to extract data from the CVR, readings from the flight data recorder revealed important details about the doomed flight. It showed the aircraft took off from Ouagadougou, the capital of Burkina Faso, with a normal and uneventful climb that continued until the plane stabilized at its cruise altitude. Two minutes after starting its cruise at 518 kilometers (322 miles) per hour, however, the aircraft`s speed began to drop progressively while the plane remained at flight level 310. To avoid an area of severe weather, the pilots later made "moderate route changes," which investigators described as "typical" in such circumstances. About 22 minutes after take-off, as it flew to a region experiencing severe weather, the plane began descending progressively while the speed continued to drop, which at this point was down to about 296 kilometers (184 miles) per hour. Eight minutes later, the aircraft turned left and quickly lost altitude with large changes in pitch and bank, BEA said. "The rotation to the left continued until the end of the recording," the investigators explained in their preliminary report. The last recorded point, at 0147:15 GMT, corresponds to an altitude of 487 meters (1,600 feet) and suggests the aircraft crashed into the surface at a speed of 703 kilometers (437 miles) per hour. Investigators expect to release an interim report in mid-September and have refused to rule out any possible causes. Aviation experts, however, said the new information points to a combination of pilot error and severe weather as a possible explanation, saying the aircraft may have experienced a stall when it crashed. The McDonnell Douglas MD-83 aircraft - owned by Spanish charter company Swiftair and operated by Air Algerie under flight number AH5017 - disappeared from radar about 32 minutes after it took off from Ouagadougou at 0117 GMT on July 24. It was en-route to Algiers, Algeria, with 110 passengers and six crew members on board. Most of the victims were French nationals. With 116 fatalities in the crash of Flight AH5017, the accident was the worst aviation disaster in Mali`s history, surpassing the crash of an Air Mali plane nearly three decades ago. That accident happened in February 1985 when an Antonov 24B aircraft went down near Timbuktu Airport, killing all but one of the 52 people on board.
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