7-cylinder man
Honestly, do you amateurs know nothing? Read and think why the FDR was recording what it was. It's all there.
An IRS/AHARS failure shouldn't lead to the loss of an aircraft - it's not even classes as an emergency procedure in any type I've flow; abnormal procedure yes.
From what has been published of the CVR recording the failure was never addressed or diagnosed by the crew. The PF seems to have jumped to a conclusion rather than diagnose the situation.
Put simple, the failure was not diagnosed by the crew and there was a rush to an incorrect conclusion.
I am intrigued. What is it in the FDR that is so simple we simpletons haven't figured it out? What was the actual failure according to you? What do you know about the FDR data that tells you about what actually went wrong?
I can agree that loss of one instrument or reading should not lead to loss of an aircraft. Still, that happens. Most of the times during night with no visual references. Just as in this case. That is sad.
On another note, I still wonder what might have broken with such short notice as hinted at on the CVR. The crew offers a few expletives and then the plane crashes within 90 seconds. Things went downhill even faster than any Airbus during malfunctioning FOs.
As Mr 7-cylinder man says, there are no clear indication on the CVR what went wrong. Some hints by the FO that they disagree on what direction to bank... maybe, depending on how you read it. Whatever happened it did so very sudden (as I read the CVR) and the crew was more occupied with trying to fly the plane than communicating with anyone. Is it possible that this lack of communication between the pilots indicates that they had the same (wrong) mental picture of the situation? May they both have been fed the wrong information somehow?