What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
The pilot of this experimental rotorway helicopter reported that it had just began an assent from a practice rapid decent when it lost tail rotor control. He reported that the aircraft experienced 1 1/2 horizontal rotations before landing in a corn field. The right skid partially buckled and the craft rolled to the right 90 degrees. It caught fire and the entire bubble/fuselage was consumed. The pilot and one passenger escaped without injury.
Examination of the tail boom and belt drive system indicated that the middle or intermediate tail rotor drive belt had broken. The primary belt was consumed in the fire. The final drive belt was intact and in place. The broken secondary drive belt was recovered and sent to the NTSB for analysis.
Of note, the secondary drive belt had broken approximately one month ago. The replacement belt had approximately 4 hours total time.
The pilot had performed numerous engine runs, & hover, and adjusting the belt tensions after each. He stated that he had flown around the pattern at mce without problem, then checked the belts, without any adjustment necessary.
Visual examination of the broken belt found two other places where the belt appeared to be weakened, unknown if from manufacturer or stress from use.
As the FAA filed it
THE PILOT OF THIS EXPERIMENTAL ROTORWAY HELICOPTER REPORTED THAT IT HAD JUST BEGAN AN ASSENT FROM A PRACTICE RAPID DECENT WHEN IT LOST TAIL ROTOR CONTROL. HE REPORTED THAT THE AIRCRAFT EXPERIENCED 1 1/2 HORIZONTAL ROTATIONS BEFORE LANDING IN A CORN FIELD. THE RIGHT SKID PARTIALLY BUCKLED AND THE CRAFT ROLLED TO THE RIGHT 90 DEGREES. IT CAUGHT FIRE AND THE ENTIRE BUBBLE/FUSELAGE WAS CONSUMED. THE PILOT AND ONE PASSENGER ESCAPED WITHOUT INJURY.
EXAMINATION OF THE TAIL BOOM AND BELT DRIVE SYSTEM INDICATED THAT THE MIDDLE OR INTERMEDIATE TAIL ROTOR DRIVE BELT HAD BROKEN. THE PRIMARY BELT WAS CONSUMED IN THE FIRE. THE FINAL DRIVE BELT WAS INTACT AND IN PLACE. THE BROKEN SECONDARY DRIVE BELT WAS RECOVERED AND SENT TO THE NTSB FOR ANALYSIS.
OF NOTE, THE SECONDARY DRIVE BELT HAD BROKEN APPROXIMATELY ONE MONTH AGO. THE REPLACEMENT BELT HAD APPROXIMATELY 4 HOURS TOTAL TIME.
THE PILOT HAD PERFORMED NUMEROUS ENGINE RUNS, & HOVER, AND ADJUSTING THE BELT TENSIONS AFTER EACH. HE STATED THAT HE HAD FLOWN AROUND THE PATTERN AT MCE WITHOUT PROBLEM, THEN CHECKED THE BELTS, WITHOUT ANY ADJUSTMENT NECESSARY.
VISUAL EXAMINATION OF THE BROKEN BELT FOUND TWO OTHER PLACES WHERE THE BELT APPEARED TO BE WEAKENED, UNKNOWN IF FROM MANUFACTURER OR STRESS FROM USE.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.