Wednesday, August 23, 2017

Bell 206B, N6259C, Helicopter Parts International Inc: Accident occurred August 20, 2017 at Minden–Tahoe Airport (KMEV), Douglas County, Nevada

Aviation Accident Final Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

Location: Minden, NV
Accident Number: GAA17CA495
Date & Time: 08/20/2017, 1230 PDT
Registration: N6259C
Aircraft: BELL 206
Aircraft Damage: Substantial
Defining Event: Loss of tail rotor effectiveness
Injuries: 5 None
Flight Conducted Under: Part 91: General Aviation - Personal

Analysis

The pilot of the helicopter reported that, during landing, the helicopter "encountered LTE [loss of tail rotor effectiveness]." He added that he maneuvered the helicopter to an open field adjacent to the intended helipad and that the tail rotor impacted a barbed wire fence.

The helicopter sustained substantial damage to the empennage.

The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation.

The Federal Aviation Administration's Helicopter Flying Handbook, FAA-H-8083-21A, contained a section titled "Loss of Tail Rotor Effectiveness (LTE)," which stated:

Loss of tail rotor effectiveness (LTE) or an unanticipated yaw is defined as an uncommanded, rapid yaw towards the advancing blade which does not subside of its own accord. It can result in the loss of the aircraft if left unchecked. It is very important for pilots to understand that LTE is caused by an aerodynamic interaction between the main rotor and tail rotor and not caused from a mechanical failure. Some helicopter types are more likely to encounter LTE due to the normal certification thrust produced by having a tail rotor that, although meeting certification standards, is not always able to produce the additional thrust demanded by the pilot.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot's failure to maintain helicopter control during landing due to a loss of tail rotor effectiveness.

Findings

Aircraft
Prop/rotor parameters - Not attained/maintained (Cause)

Personnel issues
Aircraft control - Pilot (Cause)

Environmental issues
Fence/fence post - Contributed to outcome

Factual Information

History of Flight

Landing
Loss of tail rotor effectiveness (Defining event)
Attempted remediation/recovery
Collision with terr/obj (non-CFIT)
  
Pilot Information

Certificate: Private
Age: 63, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Right
Other Aircraft Rating(s): Helicopter
Restraint Used: 4-point
Instrument Rating(s): None
Second Pilot Present:No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Class 3 Without Waivers/Limitations
Last FAA Medical Exam: 12/05/2016
Occupational Pilot: No
Last Flight Review or Equivalent: 05/13/2017
Flight Time:  (Estimated) 664 hours (Total, all aircraft), 562 hours (Total, this make and model)
  
Aircraft and Owner/Operator Information

Aircraft Manufacturer: BELL
Registration: N6259C
Model/Series: 206 B
Aircraft Category: Helicopter
Year of Manufacture: 1971
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 703
Landing Gear Type: Skid;
Seats: 5
Date/Type of Last Inspection: 05/11/2017, Annual
Certified Max Gross Wt.: 3200 lbs
Time Since Last Inspection: 
Engines: 1 Turbo Shaft
Airframe Total Time: 22237.4 Hours as of last inspection
Engine Manufacturer: Rolls Royce
ELT:  C126 installed, activated, did not aid in locating accident
Engine Model/Series: 250-C20B
Registered Owner:  HELICOPTER PARTS INTERNATIONAL INC
Rated Power: 320 hp
Operator: HELICOPTER PARTS INTERNATIONAL INC
Operating Certificate(s) Held:  None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light:  Day
Observation Facility, Elevation: KMEV, 4726 ft msl
Observation Time: 1953 UTC
Distance from Accident Site: 0 Nautical Miles
Direction from Accident Site:  71°
Lowest Cloud Condition: Clear
Temperature/Dew Point: 25°C / 7°C
Lowest Ceiling: None
Visibility:  10 Miles
Wind Speed/Gusts, Direction: Light and Variable, Variable
Visibility (RVR): 
Altimeter Setting: 30.17 inches Hg
Visibility (RVV):  
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: 
Type of Flight Plan Filed: None
Destination: Minden, NV (MEV)
Type of Clearance: None
Departure Time:
Type of Airspace: Class G

Airport Information

Airport: MINDEN-TAHOE (MEV)
Runway Surface Type: Grass/turf
Airport Elevation: 4731 ft
Runway Surface Condition: Dry
Runway Used: N/A
IFR Approach: None
Runway Length/Width: 
VFR Approach/Landing: Full Stop; Straight-in

Wreckage and Impact Information

Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: 4 None
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 5 None
Latitude, Longitude:  38.998333, -119.757222 (est)

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Las Vegas, Nevada

Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

Helicopter Parts International Inc: http://registry.faa.gov/N6259C

NTSB Identification: GAA17CA495
14 CFR Part 91: General Aviation
Accident occurred Sunday, August 20, 2017 in Minden, NV
Aircraft: BELL 206, registration: N6259C
Injuries: 5 Uninjured.

NTSB investigators used data provided by various entities, including, but not limited to, the Federal Aviation Administration and/or the operator and did not travel in support of this investigation to prepare this aircraft accident report.

The pilot of the helicopter reported that, during landing, the helicopter "encountered LTE [loss of tail rotor effectiveness]". He added that he maneuvered the helicopter to an open field adjacent to the intended helipad and the tail rotor impacted a barbed wire fence.

The helicopter sustained substantial damage to the empennage.

The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation.

Federal Aviation Administration's Helicopter Flying Handbook, FAA-H-8083-21A, contains a section titled "Loss of Tail Rotor Effectiveness (LTE)" which states:

Loss of tail rotor effectiveness (LTE) or an unanticipated yaw is defined as an uncommanded, rapid yaw towards the advancing blade which does not subside of its own accord. It can result in the loss of the aircraft if left unchecked. It is very important for pilots to understand that LTE is caused by an aerodynamic interaction between the main rotor and tail rotor and not caused from a mechanical failure. Some helicopter types are more likely to encounter LTE due to the normal certification thrust produced by having a tail rotor that, although meeting certification standards, is not always able to produce the additional thrust demanded by the pilot.

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