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April 6, 2010 · Robinson R44 Undesignat · N688SS

Temecula, CA

Overview

Report Status
Final with probable cause
Event Type
Accident
Date
April 6, 2010
Injury Outcomes
No injuries (3 uninjured)
Location
Temecula, CA
Aircraft
Robinson R44 Undesignat
Tail Number
N688SS
Operator
Twin Air
Injuries
None
Aircraft Damage
Substantial
NTSB Number
WPR10CA192

The pilot stated that he and two passengers traveled to a friend's private residence in the accident helicopter and landed on a hill with a slope. They were at the residence for a few hours before they got back in the helicopter to travel home. During their visit, the wind direction had become variable and produced a tailwind to the parked position of the helicopter. The pilot stated that prior to takeoff he did not reposition the helicopter directly into the wind while it was on the ground, as he felt the wind was not that strong. During takeoff, as the helicopter lifted off the ground and into a hover, the pilot started a right turn to position the helicopter into the wind. The helicopter drifted left of the landing pad area and the pilot recalled the helicopter spinning to the right faster than he had anticipated and he counteracted by adding additional power and left pedal to slow the rate of turn. As the helicopter was in the turn, he heard the low rpm warning and the low rotor rpm warning light illuminated. The pilot then attempted to enter a hover autorotation; however, the helicopter did not make the landing pad. The helicopter touched down on the slope of the hill and rolled over. The pilot stated that there were no mechanical problems with the helicopter prior to the accident.

NTSB Probable Cause

Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Prop/rotor parameters-Not attained/maintained - C

Full Narrative

The pilot stated that he and two passengers traveled to a friend's private residence in the accident helicopter and landed on a hill with a slope. They were at the residence for a few hours before they got back in the helicopter to travel home. During their visit, the wind direction had become variable and produced a tailwind to the parking position of the helicopter. The pilot stated that prior to takeoff he did not reposition the helicopter directly into the wind while it was on the ground, as he felt the wind was not that strong. During takeoff, as the helicopter lifted off the ground and into a hover, the pilot started a right turn to position the helicopter into the wind. The helicopter drifted left of the landing pad area and the pilot recalled the helicopter spinning to the right faster than he had anticipated and he counteracted by adding additional power and left pedal to slow the rate of turn. As the helicopter was in the turn, he heard the low rpm warning and the low rotor rpm warning light illuminated. The pilot then attempted to enter a hover autorotation; however, the helicopter did not make the landing pad. The helicopter touched down on the slope of the hill and rolled over. The pilot stated that there were no mechanical problems with the helicopter prior to the accident.

Flight

Event TypeAccident
Event Time11:00 PDT
Nearest AirportPrivate Helipad (0nm)
Flight Plan FiledNone
Flight Plan ActivatedNo
Aircraft FireNo

Aircraft

AircraftRobinson R44 Undesignat
Tail NumberN688SS
Aircraft CategoryHeli
DamageSubstantial
OperatorTwin Air
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsTextron Lycoming · O-540-F1B5 · Reciprocating · 225

People & Injuries

Injury SummaryNo injuries (3 uninjured)
Fatal0
Serious0
Minor0
Uninjured3
Total3
Crew 1Age 53 · Third Class · None

Conditions

ConditionsVMC
LightDaylight
WindCalm
Visibility50 sm
CeilingNone
Temperature / Dew Point70 F / 0 C
Altimeter30.14 inHg
Weather SourcePILO

Appendix: Source Data