Impartiality?
Unfortunately, not all air accident investigations meet the standards we expect. I am thinking of the disgraceful early leak of internal information from the NTSB investigation team engaged on the Egyptian accident. In that particular case, a verdict of suicide-murder was effectively passed upon one of the crew long before the investigators had finished exploring all possibilities. A new twist on the old 'pilot error' verdict scenario? Perhaps, perhaps not, but well outside the customary impartiality expected of investigations. Such a conclusion ought only to be made after exhaustive consideration of all other possibilities; certainly not immediately after the initial examination of CVR and DFDR data. The investigation would have stopped right there if not for external argument. In the end I am satisfied that a correct "probable cause" was established and published, but it was informed "speculation" in a number of public fora including this one, that obliged the NTSB to knuckle down and do the job properly. Speculation can and does have positive as well as negative outcomes.
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Through difficulties to the cinema