What is an “aeronautically qualified witness”? Many older NTSB AARs, in their history-of-flight-and/or-accident-sequence sections, make mention of observations by an “aeronautically qualified witness” or witnesses, without any further explanation of what this term means.  Example (AAR 76-04, page 3 [paper]/6 [PDF]):


  An aeronautically qualified witness, who was standing near the base of the radio tower when the plane struck, stated that the sky was overcast and that the bottoms of the clouds were obscuring the top 30 feet of the tower.  [...]


What, exactly, is meant by an “aeronautically qualified witness”?  Does it mean “a witness who is themself a pilot”?
It means a witness with credentials and knowledge that makes the witness competent to give a reasonably accurate description of an event, or an informed opinion, to an investigating authority or a jury.  Likely a pilot witness to a crash as in this case, who knows more about weather than the average person, or a mechanic witness in an investigation or lawsuit over maintenance.