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NTSB Report
April 18, 2018 · Robinson Helicopter R44 Undesignat · N4487D
Sonora, TX
Overview
Report Status
Final with probable cause
Event Type
Accident
Date
April 18, 2018
Injury Outcomes
No injuries (2 uninjured)
Location
Sonora, TX
Aircraft
Robinson Helicopter R44 Undesignat (2006)
Tail Number
N4487D
Injuries
None
Aircraft Damage
Substantial
NTSB Number
GAA18CA247
The pilot reported that, while he was spotting deer, the helicopter hit a treetop, damaging the tail rotor. The helicopter began to spin, and the pilot closed the throttle. He landed the helicopter, and it then rolled onto its left side. The helicopter sustained substantial damage to the tailboom and fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation. The pilot's recommendation was to fly at a higher and safer altitude.
NTSB Probable Cause
Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Altitude-Not attained/maintained - C
Full Narrative
The pilot reported that, while spotting deer, the helicopter hit the top of a tree damaging the tail rotor. The helicopter began to spin, and the pilot closed the throttle. The helicopter landed and rolled onto its left side. The helicopter sustained substantial damage to the tail boom and fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation. The pilot's recommendation was to fly at a higher and safer altitude.
Flight
Event TypeAccident
Event Time11:00 CDT
Nearest Airport0nm
Flight Plan FiledUnknown
Flight Plan ActivatedUnknown
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftRobinson Helicopter R44 Undesignat
Tail NumberN4487D
Aircraft CategoryHeli
DamageSubstantial
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-540-F1B5 · Reciprocating · 260
Seats4
People & Injuries
Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 36 · Second Class · None
Conditions
ConditionsVMC
LightDaylight
Wind10° @ 12 kt, gusting 21 kt
Visibility10 sm
CeilingBroken clouds 2300 ft
Temperature / Dew Point70 F / 59
Altimeter30.11 inHg
Observation Time16:15
Weather SourceWFAC