Quite a ride for a newer pilot to master. Probable cause: The pilot's failure to recognize the need for, and to take action to maintain, sufficient airspeed to prevent a stall into the ground during an attempted landing. The pilot also failed to recognize the need for timely and sufficient power application to prevent the stall during an approach conducted inadvertently without flaps extended.
Contributing to the pilot's inability to recognize the problem and to take proper action was his failure to use the appropriate checklist, and his nonstandard pattern procedures which resulted in an abnormal approach profile.
All indications were that Munson had no business piloting a jet with so little flight time in one of them. He had just “graduated” from several smaller prop aircraft that he had owned previously.
I recall reading in Graig Nettles’ book BALLS about what happened and that in Graig’s words Thurman moved up to that type of plane too fast.