TWT wrote:
Be better if the recovered CSMU was sent straight to Honeywell for readout.Could be a tricky data extraction process,may as well be attempted by the best qualified hands the first time.
I think you are alluding to the Perpignan accident? Those recorders (same models as on AF447 btw) were recovered after just 2 and 3 days, respectively, from a depth of only 40 meters. Nevertheless BEA spent a whole month on unsuccessful attemps to read the memory cards and then gave up. From the report: "They were examined at Honeywell, manufacturer of the recorders, in the United States on 5 and 6 January 2009 in the context of an International Commission of Inquiry. Some short-circuits were discovered on the cards. Eliminating the short-circuits allowed a complete read-out of the data."
But it seems that BEA have learnt from this experience and are getting better. Here's a summary of their participation in the Yemenia crash:
Point d'information, 30 juin 2010 . I've found no English translation on their website, so here's my own attempt:
4. Flight recorder readings
The flight recorders were recovered on 29 August 2009 and, on request of the Comorean authorities, immediately transported to the BEA. Due to the damaged state of the memory cards, data extraction required two weeks work. Nevertheless, the major part of the information contained in the two recorders (one for the aircraft parameters, the other for the flight deck conversations) could be read. This readout was done in the presence of all members of the international investigation committee, and of a representative from Honeywell, manufacturer of the recorder. It allowed, in the opinion of BEA, to determine the circumstances that have led to the accident [...].