AFP: Algerialaiskone kateissa

[Sami Puro 612]

Ohjaamonauhurihan löydettiin melko pian, mutta nyt on käynyt ilmi että nauhuri ei ole toiminut, ja tämä mutkistaa tutkimuksia melko paljon. Alunperin arveltiin että törmäys olisi hajottanut sen, mutta tutkijat uskovat sen olleen viallinen jo aiemmin. FDR toimi ja tiedot on saatu ulos.

 

http://atwonline.com/safety/air-algerie-crash-probe-complicated-cvr-malfunction

 

Air accident investigators probing the crash of an MD-83 operating for Air Algerie have revealed the aircraft’s cockpit voice recorder (CVR) was potentially broken before the accident.

 

France’s Bureau d'Enquêtes et d'Analyses (BEA) originally said the CVR was damaged on impact, but the latest evidence suggests the device was already faulty.

 

“The magnetic tape in the CVR, which was damaged, was repaired and read out. Unfortunately, the recordings that it contains are unusable, due apparently to a recorder malfunction, with no link to the damage that resulted from the accident,” BEA said. “The absence of usable data from the CVR at present underlines the need to collect all data on communications that the crew may have made with organizations on the ground or with other aircraft.”

 

Information from the flight data recorder (FDR) has been used to piece together an initial picture of the MD-83’s flight path. This will be supplemented with aircraft and engine performance data to create a more accurate record of what happened.

 

“The aeroplane’s flight path as it was reconstituted from the FDR data, superimposed over a satellite image of the cloud mass present on the day of the accident, shows a normal climb and start of cruise, with some moderate route changes that are typical of a strategy to avoid any stormy developments,” BEA said.

 

The FDR data shows the MD-83 took off from Ouagadougou and climbed to FL310, where it reached a cruise speed of about 280kt. However, after this there were some abnormalities.

 

“Around two minutes after the start of cruise, while remaining at flight level 310, the speed dropped progressively. The aircraft began descending progressively and the speed continued to drop down to about 160kt.”

 

The aircraft then turned left and quickly lost altitude, with large changes in pitch and bank. The rotation to the left continued until the end of the recording. The last recorded point, 1h47mn15s, corresponds to an altitude of 1,600ft, a speed of about 380kt and an extremely high descent speed,” BEA said.