Former TV journalist Vaughan, who lives in Katikati, was flying over Waihī in March last year when the windscreen of his plane exploded, forcing him to make an emergency landing.
"Suddenly the windscreen of the plane just blew out," Vaughan told NZME last year.
"One second it was there, the next second it was gone completely. It was just like being in a wind tunnel. There was just a huge amount of air racing into the cockpit."
Vaughan believed at the time that a drone was responsible for the sudden loss of the windscreen.
The Civil Aviation Authority, in a report released this week, said investigators found no trace of a drone after the crash.
The report said the pilot was viewing the Waihī mine when the windscreen failed "catastrophically".
"The sudden inflow of air caused both cabin doors to come open and aerodynamic control became compromised," it read.
Examination of the aircraft and searches of the area of the mine found no evidence of a drone, the report said.
However, during the examination of the aircraft, a discolouration of the plastic polymer windscreen was found. The windscreen was yellowing the original clear material.
Laboratory examination of the windscreen found UV degradation to upper sections of the outside of the windscreen.
This kind of degradation could result in sudden failures, the report said, but the extent to which this could impact the mechanical properties of the windscreen had not been established.