Two things have been prominently posted in today's news about the Metrojet crash in the Sinai. One focuses on the fact that the Egyptian Government is solely responsible for the crash investigation, and that the Egyptians may be withholding the truth about a terrorist bomb, for political reasons. (Supposedly protecting its tourism industry.) This assertion also points out that the Egyptians have limited access to the wreckage and also that other governments, notably the British, have taken strong actions already because they give strong credibility to a terrorist bomb having downed the Airbus.
The other news release indicates that the Cockpit Voice Recorder might have recorded the sound of an explosion. This release does not have authoritative support, particularly not from any governmental source. At this point we do not know who, other than Egyptian investigators, may have custody of the CVR and FDR, much less analyzed their contents.
I find the first of these criticisms to be premature and biased. Note that the accident involving the Indonesian Air Asia 8501 of December 28, 2014, which I have reported to be eerily similar to the Metrojet crash, is still unresolved. The Indonesian Government, in charge of the investigation, has still not released a preliminary analysis or report of its findings, even though the crash took place eleven months ago and the Government recovered the CVR and the FDR shortly after the crash. Many (if not most) professionals in the aviation industry are highly critical of early releases of information, before the accident investigation team can do it work.
As for the reported sounds in the CVR recording, this report is not credible until we know a great deal more than just a hearsay, unsubstantiated news story. Even if there were an explosive sound on the CVR, the possibility remains that the sound could have come from exploding jet fuel as the aircraft started to come apart. The investigators will be piecing together a precise time synchronization of all facts, and that will be critical in understanding what might be recorded on the CVR.