ASN Wikibase Occurrence # 293115
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can
submit corrected information.
Date: | Saturday 3 September 2005 |
Time: | 08:30 LT |
Type: | Goodlett Safari |
Owner/operator: | |
Registration: | N912TT |
MSN: | 2002 |
Total airframe hrs: | 522 hours |
Engine model: | Lycoming O-320-B2C |
Fatalities: | Fatalities: 0 / Occupants: 1 |
Aircraft damage: | Substantial |
Category: | Accident |
Location: | Trona, California -
United States of America
|
Phase: | Unknown |
Nature: | Private |
Departure airport: | Ridgecrest, CA (KPVT) |
Destination airport: | |
Investigating agency: | NTSB |
Confidence Rating: | Accident investigation report completed and information captured |
Narrative:The experimental helicopter impacted terrain after experiencing a failure of a flight control connecting rod. According to the pilot, he was maneuvering the helicopter about 50 feet above the ground when he heard a loud bang followed by a whirring or buzzing noise. The helicopter rolled to the left, which the pilot was unable to counter with control inputs, and impacted terrain on the left side. A post-accident examination of the helicopter by the pilot/builder revealed that a 27.875-inch aluminum control rod was fractured near the middle of the rod. The control rod was connected between the collective-cyclic mixing assembly and a walking beam that connected to the stationary swash plate of the left side (pilot side) of the helicopter. The break in the control rod was perpendicular to the longitudinal axis of the rod. Examination of the control rod by a metallurgical laboratory revealed the failure was a result of a fatigue crack that had propagated through nearly 75 percent of the control rod. A portion of the break was polished indicating that the crack had been present for quite some time. The pre-existing crack in the control rod reduced its strength to a point that allowed the flight control forces to fail the remaining material. According to the pilot/builder, a break in the control rod would result in flight characteristics consistent with that experienced by the pilot during the accident flight. The control system has been redesigned by the kit manufacturer as a result of this accident and now incorporates steel control rods as opposed to aluminum ones.
Probable Cause: the in-flight fatigue failure of a control system connecting rod, which resulted in a loss of helicopter control.
Accident investigation:
|
| |
Investigating agency: | NTSB |
Report number: | LAX05LA288 |
Status: | Investigation completed |
Duration: | 1 year and 5 months |
Download report: | Final report |
|
Sources:
NTSB LAX05LA288
Revision history:
Date/time | Contributor | Updates |
09-Oct-2022 16:14 |
ASN Update Bot |
Added |
The Aviation Safety Network is an exclusive service provided by:
CONNECT WITH US:
©2024 Flight Safety Foundation