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August 14, 2017 · Robinson Helicopter R44 Undesignat · N97UP

Westby, WI

Overview

Report Status
Final with probable cause
Event Type
Accident
Date
August 14, 2017
Injury Outcomes
No injuries (1 uninjured)
Location
Westby, WI
Aircraft
Robinson Helicopter R44 Undesignat (1996)
Tail Number
N97UP
Operator
Mf Helicopters
Injuries
None
Aircraft Damage
Substantial
NTSB Number
GAA17CA491

The helicopter pilot reported that, during an agricultural application flight, he performed a "high…[reconnaissance]" pass over the field and observed houses, tree lines, and power lines surrounding the field. He added that he descended for the first pass, about 70 mph and 100 to 150 ft above ground level, and as he approached the end of the field, he "suddenly became aware of two [additional] large power lines stretched out in front of [him] at eye level and closing fast." He further added that he "instinctively pulled up on the collective and back on the cyclic," and the fuselage cleared the wire, but suddenly there was a "violent lurch" when the tail rotor contacted the wire. Subsequently, the helicopter started to "spin out of control," the pilot braced for impact, and the helicopter impacted the terrain. The fuselage, tailboom, and main rotor sustained substantial damage. The pilot reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.

NTSB Probable Cause

Environmental issues-Physical environment-Object/animal/substance-Tower/antenna (incl guy wires)-Awareness of condition - C

Full Narrative

The helicopter pilot reported that, during an aerial application flight, he performed a "high recon [reconnaissance]" pass over the field and observed houses, tree lines, and power lines surrounding the field. He added that he descended for the first pass, about 70 mph and 100 to 150 ft. above ground, and as he approached the end of the field, he "suddenly became aware of two [additional] large power lines stretched out in front of [him] at eye level and closing fast." He further added that, he "instinctively pulled up on the collective and back on the cyclic" and the fuselage cleared the wire, but suddenly there was a "violent lurch" when the tail rotor contacted the wire. Subsequently, the helicopter started to "spin out of control," the pilot braced for impact, and the helicopter impacted the terrain. The fuselage, tail boom, and main rotor sustained substantial damage. The pilot reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.

Flight

Event TypeAccident
Event Time13:15 CDT
Nearest Airport0nm
Flight Plan FiledNone
Flight Plan ActivatedNo
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftRobinson Helicopter R44 Undesignat
Tail NumberN97UP
Aircraft CategoryHeli
DamageSubstantial
OperatorMf Helicopters
Operating RulePart 137
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-540-F1B5 · Reciprocating · 260
Seats4

People & Injuries

Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 34 · Second Class · None

Conditions

ConditionsVMC
LightDaylight
Wind120° @ 5 kt
Visibility10 sm
CeilingNone
Temperature / Dew Point0 C
Altimeter0
Observation Time18:15
Weather SourcePILO

Appendix: Source Data