- Date
- August 20, 2017, 12:30 local (19:30 UTC)
- Place
- Minden, NV
- Injuries
- 5 uninjured
- Damage
- Substantial damage
- Phase of flight
- Landing
- Aircraft
- N6259CBell 206
- Defining event
- Landing: Loss of tail rotor effectiveness
- Weather
- Visual (VMC) · Day
- Status
- Completed · report November 27, 2017
- Report
- Approved by Office Director
- NTSB office
- General Aviation Accidents
- Parties
- FAA
- FAA report
- 20170820010439A
- Case key
- 95841
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
The pilot’s failure to maintain helicopter control during landing due to a loss of tail rotor effectiveness.
Findings · 3
NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.
Sequence of events
The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.
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.
Factual narrative
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.
Aircraft
- Registration
- N6259C
- Reported as
- Bell 206 (B)
- Category
- Helicopter
- Serial number
- 703
- Built
- 1971
- Airframe hours
- 22,237.4
- Engine
- Rolls Royce 250-C20B, 320 horsepower, turbo shaft
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Operator
- Helicopter Parts International Inc
- Registered owner
- Helicopter Parts International Inc
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · May 11, 2017
- Destination
- MEV · Minden, NV
- Airport
- MEV · Minden-Tahoe
- Equipment
- None
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 63
- Injuries
- None
- Certificate
- Private
- Airplane ratings
- Single-engine land
- Medical
- Class 3, Without waivers/limitations
- Last flight review
- May 13, 2017
- Seat
- Right
- Restraint
- 4-point
- Flight hours
- 664 total · 562 in this make and model
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- Variable at 3 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 77 °F, dew point 45 °F
- Altimeter
- 30.17 inHg
- Observed at
- KMEV
Docket · 2
The files NTSB released with the investigation on October 31, 2017, on NTSB’s docket system: statements, records, photos and specialists’ reports. 975 KB in all.
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.