NTSB Identification: FTW87LA195.
The docket is stored on NTSB microfiche number 33901.
Accident occurred Wednesday, August 12, 1987 in NEW IBERIA, LA
Probable Cause Approval Date: 05/02/1988
Aircraft: BELL 206L-1, registration: N2764F
Injuries: 2 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

CREW PERFORMING PRACTICE TOUCHDOWN AUTOROTATIONS DURING A TRNG FLT. ON 4TH AUTOROTATION, ACFT TOUCHED DOWN WITH EXCESS GRND SPEED AND SKIDDED FOR APPROX 75' ON THE WET, SOFT GRASS. WHEN CREW APPLIED POWER BACK TO FLIGHT RPM THEY HEARD A GRINDING SOUND AND FELT A VIBRATION. VISUAL INSP REVEALED THAT THE TAILBOOM HAD SEPARATED AFT OF THE ATTACHMENTS DUE TO RESONANCE. THIS ACFT IS SUBJECT TO RESONANCE IF ROTOR RPM IS ALLOWED TO DECAY BELOW 70% DURING TOUCHDOWN AUTOROTATIONS OR DURING LENGTHY GROUND RUNS.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

MISC ROTORCRAFT,TAIL BOOM..FAILURE,TOTAL

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

AUTOROTATION..PERFORMED..DUAL STUDENT

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

MISC ROTORCRAFT,TAIL BOOM..VIBRATION

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

RUN ON LANDING..PERFORMED..DUAL STUDENT

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

AIRSPEED..MISJUDGED..DUAL STUDENT

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

SUPERVISION..INADEQUATE..PILOT IN COMMAND(CFI)


Contributing Factors

TERRAIN CONDITION..SOFT

Index for Aug1987 | Index of months