Witnesses said worker Kevin Connolly was performing a test on the helicopter at the airport at 3:30 p.m. Friday when the chopper began to shudder.
Connolly was then thrown from the pilot's seat through the front windshield and struck by the rotating blades, according to the report.
Mechanics can do ground runs after being properly trained and certified for those procedures. General rule is all controls neutral and collective fully down....but varies by company.