Originally Posted by
P-air
I guess one of the first things the co-conspirators do after landing would be to wipe the CVR and DVDR, thus we may never know what happened even if the aircraft is found if it landed safely somewhere.
While some, (though not all) CVRs can have their stored audio erased on the ground by the press of a button, this is not the case with the DFDR. The only way that the Flight Data Recorder's contents could be "wiped" would be to remove it from its mounting rack and physically destroy it, or hide it where it could not be found.
However... although there is as yet no hard evidence that one (or both) pilots went "rogue" , and deliberately engineered the disappearance of the aircraft, IF that does turn out to be the case, I'd be willing to bet a month's salary that both the CVR and DFDR were disabled very early on by pulling their respective circuit breakers - meaning that even if the aircraft is eventually found, (either intact or in small pieces), that the "black boxes" will contain absolutely no data whatsoever covering the critical stages of the final flight.
That scenario would require that the CVR and DFDR CBs be in a location readily accessible to the flight crew. I have no idea if this is the case with the 777, but on all of the business jets I maintain, (Hawkers, Gulfstreams, EMB-135 etc) the CBs for both the CVR and DFDR are located on the flight deck, within easy reach of the crew.