What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) This flight was a hillsborough county sheriff's dept. "Public use" a/c flight. VMC daylight conditions prevailed and the wind was down the rwy at 5 knots. This heli flight was to be a 90 day pilot competency ride. The a/c set up to do a 180 degree autorotation. The instructor stated he told the pilot to add some collective to keep the rotor balde from "over speeding". As the heli completed 180 degrees turn the rotor RPM was middle green arc. The instructor said he asked the pilot to add throttle to increase the rotor RPM to initial a power recovery. (That there was a droop, the RPM never fully recovered, and that the heli touched down in a level flat attitude but that the tailboom deformed and cracked but remained attached to the heli). The heli bounced and was set down in a hover several feet down the rwy. The crew shut the a/c down and it was towed to the hanger. The tailboom component was destroyed and further tests are being conducted to see if other components exceeded tolerance.
As the FAA filed it
(-23) THIS FLIGHT WAS A HILLSBOROUGH COUNTY SHERIFF'S DEPT. "PUBLIC USE" A/C FLIGHT. VMC DAYLIGHT CONDITIONS PREVAILED AND THE WIND WAS DOWN THE RWY AT 5 KNOTS. THIS HELI FLIGHT WAS TO BE A 90 DAY PILOT COMPETENCY RIDE. THE A/C SET UP TO DO A 180 DEGREE AUTOROTATION. THE INSTRUCTOR STATED HE TOLD THE PILOT TO ADD SOME COLLECTIVE TO KEEP THE ROTOR BALDE FROM "OVER SPEEDING". AS THE HELI COMPLETED 180 DEGREES TURN THE ROTOR RPM WAS MIDDLE GREEN ARC. THE INSTRUCTOR SAID HE ASKED THE PILOT TO ADD THROTTLE TO INCREASE THE ROTOR RPM TO INITIAL A POWER RECOVERY. (THAT THERE WAS A DROOP, THE RPM NEVER FULLY RECOVERED, AND THAT THE HELI TOUCHED DOWN IN A LEVEL FLAT ATTITUDE BUT THAT THE TAILBOOM DEFORMED AND CRACKED BUT REMAINED ATTACHED TO THE HELI). THE HELI BOUNCED AND WAS SET DOWN IN A HOVER SEVERAL FEET DOWN THE RWY. THE CREW SHUT THE A/C DOWN AND IT WAS TOWED TO THE HANGER. THE TAILBOOM COMPONENT WAS DESTROYED AND FURTHER TESTS ARE BEING CONDUCTED TO SEE IF OTHER COMPONENTS EXCEEDED TOLERANCE.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.