ASN Wikibase Occurrence # 34352
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 27 September 2008 |
Time: | 13:00 |
Type: | Bell 206B JetRanger |
Owner/operator: | private |
Registration: | N59611 |
MSN: | 1515 |
Year of manufacture: | 1974 |
Total airframe hrs: | 2519 hours |
Engine model: | Rolls-Royce Allison 250-C20 |
Fatalities: | Fatalities: 0 / Occupants: 1 |
Aircraft damage: | Substantial |
Category: | Accident |
Location: | Laramie, WY -
United States of America
|
Phase: | Manoeuvring (airshow, firefighting, ag.ops.) |
Nature: | Private |
Departure airport: | Laramie, WY |
Destination airport: | Laramie, WY |
Investigating agency: | NTSB |
Confidence Rating: | Accident investigation report completed and information captured |
Narrative:The pilot reported that he was flying over his ranch property at about 50 knots looking for stray cattle when "...a strong tailwind or twister caused the ship to vibrate very fast and violent, and dove to the right." The pilot stated that several people on the ground observed the helicopter spin 5 to 6 times before impacting the uneven and sloping ground and rolling over. The pilot further stated, "I couldn't get response from the tail rotor, collective, or cyclic." The ranch foreman saw the helicopter making a "big circle," followed by 3 or 4 "tight circles" in a clockwise direction before impacting terrain. A post crash examination of the helicopter by a Federal Aviation Administration (FAA) aviation safety inspector revealed no apparent malfunctions. The pilot reported no preimpact anomalies with the helicopter. The Rotorcraft Flying Handbook states that a loss of tail rotor effectiveness (LTE) is the occurrence of an uncommanded yaw rate that does not subside on its own accord, which can result in the loss of helicopter control. The recovery technique for LTE is full left pedal while simultaneously moving cyclic control forward to increase airspeed. If altitude permits, reduce power. FAA Advisory Circular 90-95 states, "Any maneuver which requires the pilot to operate in a high-power, low-airspeed environment with a left crosswind or tailwind creates an environment where unanticipated right yaw may occur."
Probable Cause: The pilot's encounter with a loss of tail rotor effectiveness event and his failure to maintain directional control while maneuvering. Contributing to the accident were the tailwind condition and the sloping, uneven terrain.
Accident investigation:
|
| |
Investigating agency: | NTSB |
Report number: | SEA08LA213 |
Status: | Investigation completed |
Duration: | 5 months |
Download report: | Final report |
|
Sources:
NTSB
Location
Revision history:
Date/time | Contributor | Updates |
01-Aug-2015 19:32 |
TB |
Updated [Plane category] |
03-Dec-2017 12:04 |
ASN Update Bot |
Updated [Time, Operator, Other fatalities, Nature, Departure airport, Destination airport, Source, Narrative] |
The Aviation Safety Network is an exclusive service provided by:
CONNECT WITH US:
©2024 Flight Safety Foundation