What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) No narrative (.4) the solo student pilot was practicing quick stop maneuvers. He reported that, during one maneuver, the helicopter was nearly stopped in a high hover at 30 feet AGL, and he was descending to low hover when the helicopter started vibrating and yawed to the left. The controls became ineffective and the helicopter started spinning around until it impacted the ground and then rolled on its side. When examined after the accident, the main rotor blades exhibited modest leading edge damage, modest chordwise striations, and approximately 20 degrees of uniform root-to-tip upward bending deformation. One tail rotor blade was undamaged and the other was bent about 10 degrees tip-inboard at the midspan. The engine was started and ran smoothly. No preaccident mechanical anomalies were noted. The national transportation safety board determines the probable cause(s) of this accident as follows. The student's improper execution of a quick-stop maneuver in that he misjudged his altitude and failed to terminate at a stationary hover prior to descending to a low hover. This resulted in an excessive engine power requirement and the student improperly coordinated the use of the collective and anti-torque controls.
As the FAA filed it
(-23) NO NARRATIVE (.4) THE SOLO STUDENT PILOT WAS PRACTICING QUICK STOP MANEUVERS. HE REPORTED THAT, DURING ONE MANEUVER, THE HELICOPTER WAS NEARLY STOPPED IN A HIGH HOVER AT 30 FEET AGL, AND HE WAS DESCENDING TO LOW HOVER WHEN THE HELICOPTER STARTED VIBRATING AND YAWED TO THE LEFT. THE CONTROLS BECAME INEFFECTIVE AND THE HELICOPTER STARTED SPINNING AROUND UNTIL IT IMPACTED THE GROUND AND THEN ROLLED ON ITS SIDE. WHEN EXAMINED AFTER THE ACCIDENT, THE MAIN ROTOR BLADES EXHIBITED MODEST LEADING EDGE DAMAGE, MODEST CHORDWISE STRIATIONS, AND APPROXIMATELY 20 DEGREES OF UNIFORM ROOT-TO-TIP UPWARD BENDING DEFORMATION. ONE TAIL ROTOR BLADE WAS UNDAMAGED AND THE OTHER WAS BENT ABOUT 10 DEGREES TIP-INBOARD AT THE MIDSPAN. THE ENGINE WAS STARTED AND RAN SMOOTHLY. NO PREACCIDENT MECHANICAL ANOMALIES WERE NOTED. THE NATIONAL TRANSPORTATION SAFETY BOARD DETERMINES THE PROBABLE CAUSE(S) OF THIS ACCIDENT AS FOLLOWS. THE STUDENT'S IMPROPER EXECUTION OF A QUICK-STOP MANEUVER IN THAT HE MISJUDGED HIS ALTITUDE AND FAILED TO TERMINATE AT A STATIONARY HOVER PRIOR TO DESCENDING TO A LOW HOVER. THIS RESULTED IN AN EXCESSIVE ENGINE POWER REQUIREMENT AND THE STUDENT IMPROPERLY COORDINATED THE USE OF THE COLLECTIVE AND ANTI-TORQUE CONTROLS.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.