The microburst idea cannot be ruled out. However, the eyewitness describes the roar of the engine and how the right wing went down in a side slip posture. Jim failed to level his wings before adding power and you know what happened after that.
I explain how there was a convergence of circumstances and the major mistakes Jim made that lead to the tragedy. Not the least of which was the fact that he came back from an exhausting trip overseas and -- without having any time to practice flying -- got his license by paying a guy to give him the exam who was known around Nashville as being unduly enamored by celebrities. Jim got his license before he was thoroughly prepared to fly. Both of his main charter pilots flew with him and were aghast that he was flying on his own because it was obvious to them he was not ready yet.
The NTSB report is very brief. You need to read the book! :)
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