Narrative:

Training company employee for transition into light helicopter support ship. Company employee was demonstrating straight in power recovery automatic rotation into large open field, as he was taught in the army. Maneuver was started at approximately 800' AGL. Airspeed 60 mph. Approximately 200' AGL above landing or recovery site, employee allowed aircraft nose over slightly and accelerated in airspeed approximately 75 mph. As aircraft approached approximately 35' AGL, employee started to flare aircraft to decelerate airspeed and build rotor RPM. Flare was increased at too steep an angle and tail rotor struck ground, causing failure of the tail rotor drive system. Aircraft rebounded back into the air and began to yaw hard right. Employee froze on controls. At this time I took over the controls of the aircraft, overpwring employee. Throttle was immediately rolled off to prevent and stop yaw. Normal power off. Automatic rotation was performed. Aircraft landed west/O further incident and shut down and secured. Employee admitted he had misjudged altitude for start of flare and I added his visibility sight picture was too close in front of aircraft to see rapid change in approach angle. Prevention should have been for myself to stop the maneuver at a higher altitude and not let employee take aircraft to such a low altitude and continued approach. Student was frustrated and was too aggressive for this type of demonstration. Was trying to prove his ability to me. Training in these conditions must be closely monitored so change in student's attitude can be noticed sooner. Student was commercial rated helicopter pilot, military trained.

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Original NASA ASRS Text

Title: HELICOPTER PLT TRAINEE DEMONSTRATING AUTO ROTATION APCH AND LNDG OVERROTATED ALLOWING TAIL ROTOR TO CONTACT GND. INSTRUCTOR REGAINED CTL OF ACFT AND LANDED.

Narrative: TRNING COMPANY EMPLOYEE FOR TRANSITION INTO LIGHT HELI SUPPORT SHIP. COMPANY EMPLOYEE WAS DEMONSTRATING STRAIGHT IN PWR RECOVERY AUTO ROTATION INTO LARGE OPEN FIELD, AS HE WAS TAUGHT IN THE ARMY. MANEUVER WAS STARTED AT APPROX 800' AGL. AIRSPD 60 MPH. APPROX 200' AGL ABOVE LNDG OR RECOVERY SITE, EMPLOYEE ALLOWED ACFT NOSE OVER SLIGHTLY AND ACCELERATED IN AIRSPD APPROX 75 MPH. AS ACFT APCHED APPROX 35' AGL, EMPLOYEE STARTED TO FLARE ACFT TO DECELERATE AIRSPD AND BUILD ROTOR RPM. FLARE WAS INCREASED AT TOO STEEP AN ANGLE AND TAIL ROTOR STRUCK GND, CAUSING FAILURE OF THE TAIL ROTOR DRIVE SYS. ACFT REBOUNDED BACK INTO THE AIR AND BEGAN TO YAW HARD RIGHT. EMPLOYEE FROZE ON CTLS. AT THIS TIME I TOOK OVER THE CTLS OF THE ACFT, OVERPWRING EMPLOYEE. THROTTLE WAS IMMEDIATELY ROLLED OFF TO PREVENT AND STOP YAW. NORMAL PWR OFF. AUTO ROTATION WAS PERFORMED. ACFT LANDED W/O FURTHER INCIDENT AND SHUT DOWN AND SECURED. EMPLOYEE ADMITTED HE HAD MISJUDGED ALT FOR START OF FLARE AND I ADDED HIS VIS SIGHT PICTURE WAS TOO CLOSE IN FRONT OF ACFT TO SEE RAPID CHANGE IN APCH ANGLE. PREVENTION SHOULD HAVE BEEN FOR MYSELF TO STOP THE MANEUVER AT A HIGHER ALT AND NOT LET EMPLOYEE TAKE ACFT TO SUCH A LOW ALT AND CONTINUED APCH. STUDENT WAS FRUSTRATED AND WAS TOO AGGRESSIVE FOR THIS TYPE OF DEMONSTRATION. WAS TRYING TO PROVE HIS ABILITY TO ME. TRNING IN THESE CONDITIONS MUST BE CLOSELY MONITORED SO CHANGE IN STUDENT'S ATTITUDE CAN BE NOTICED SOONER. STUDENT WAS COMMERCIAL RATED HELI PLT, MIL TRAINED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.