Yes very sad indeed. R.I.P.
Not to take anything away from the deceased or speculate on the cause of this tragedy, I wonder if the pilot's were test pilots. I.E., production test pilot's from the factory? If they weren't they should have been. I do admire the attitude of the AME's having the courage to be on board. However a test pilot/pilot's would have had the appropriate engineering qualifications. Insurance companies would need to look at this, if they already haven't. If a Learjet series aircraft, for example, was to have certain leading edge devices replaced or adjusted,, a factory test pilot must carry out a flight test, prior to normal operations.
Read somewhere the aircraft had 6 years of major work carried out on it and hadn't flown for 9 years. You can guarantee there would have been a stack of paperwork (at least as high as the building it almost hit) associated with the aircraft, before the DGCA would have even thought about letting it get airborne.. "A chain is only as strong as it's weakest link". .As mentioned above, WX needs to be good before carrying out such a venture.
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