What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
B407 main rotor contacted the left vertical finlet during landing. Aircraft was towed back to the hangar. Delayed notification. On advice from manufacturer engineering, maintenance personnel performed skid deflection check and determined that aircraft had sustained a hard landing. Further inspections awaitng release from NTSB and operator legal department.
The damage was found at the conclusion of 2 training flights. The pilots undergoing training swapped out between sessions with the engine running and instructor remaining at the controls. Statements from pilots undergoing training and the contract instructor state that none were aware of any abnormal landing or blade strike during the course of instruction which included numerous touchdown autorotations and other simulated emergency procedures. In subsequent interview, instructor stated that one of the pilots undergoing training may have input too much aft cyclic duirng the ground run at low rotor RPM at the completion of an autorotation while the instructor reached up to mute the low RPM audio causing the main rotor to flex down enough to strike the left finlet.
As the FAA filed it
B407 MAIN ROTOR CONTACTED THE LEFT VERTICAL FINLET DURING LANDING. AIRCRAFT WAS TOWED BACK TO THE HANGAR. DELAYED NOTIFICATION. ON ADVICE FROM MANUFACTURER ENGINEERING, MAINTENANCE PERSONNEL PERFORMED SKID DEFLECTION CHECK AND DETERMINED THAT AIRCRAFT HAD SUSTAINED A HARD LANDING. FURTHER INSPECTIONS AWAITNG RELEASE FROM NTSB AND OPERATOR LEGAL DEPARTMENT.
THE DAMAGE WAS FOUND AT THE CONCLUSION OF 2 TRAINING FLIGHTS. THE PILOTS UNDERGOING TRAINING SWAPPED OUT BETWEEN SESSIONS WITH THE ENGINE RUNNING AND INSTRUCTOR REMAINING AT THE CONTROLS. STATEMENTS FROM PILOTS UNDERGOING TRAINING AND THE CONTRACT INSTRUCTOR STATE THAT NONE WERE AWARE OF ANY ABNORMAL LANDING OR BLADE STRIKE DURING THE COURSE OF INSTRUCTION WHICH INCLUDED NUMEROUS TOUCHDOWN AUTOROTATIONS AND OTHER SIMULATED EMERGENCY PROCEDURES. IN SUBSEQUENT INTERVIEW, INSTRUCTOR STATED THAT ONE OF THE PILOTS UNDERGOING TRAINING MAY HAVE INPUT TOO MUCH AFT CYCLIC DUIRNG THE GROUND RUN AT LOW ROTOR RPM AT THE COMPLETION OF AN AUTOROTATION WHILE THE INSTRUCTOR REACHED UP TO MUTE THE LOW RPM AUDIO CAUSING THE MAIN ROTOR TO FLEX DOWN ENOUGH TO STRIKE THE LEFT FINLET.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.