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Aviation safety reports, made easier to study

NTSB Reports is an independent research and search tool for public aviation accident and incident records. It brings NTSB aviation reports, structured fields, docket files, extracted figures, photos, videos, and update history into one searchable interface.

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NTSB Report

February 26, 2011 · Hiller UH-12E · N236HA

Colusa, CA

Overview

Report Status
Final with probable cause
Event Type
Accident
Date
February 26, 2011
Injury Outcomes
No injuries (2 uninjured)
Location
Colusa, CA
Aircraft
Hiller UH-12E
Tail Number
N236HA
Injuries
None
Aircraft Damage
Substantial
NTSB Number
WPR11CA146

The pilot reported that he and the owner of the helicopter were flying a reconnaissance flight in preparation for a possible frost control flight the following morning. They were attempting to identify potential obstacles in the area. As they were flying slowly over the north edge of an almond orchard he initiated a descent, and slowed the helicopter to just above effective translational lift. He turned southbound and noted a 7- to 10-mile-per-hour tailwind. He reported that the tailwind, coupled with the descent, caused the helicopter to enter a settling with power condition. He stated that due to the close proximity of the trees he was not able to perform a normal recovery of lowering the collective and applying forward cyclic control. The helicopter descended between a row of trees and the main rotor blades struck the trees. The pilot stated that there were no mechanical malfunctions with the helicopter before the accident.

NTSB Probable Cause

The pilot's failure to maintain an adequate airspeed and an inadvertent encounter with settling with power while flying downwind.

Full Narrative

The pilot reported that when the accident occurred he and the owner of the helicopter were flying a reconnaissance flight in preparation for a possible frost control flight the following morning. They were attempting to identify potential obstacles in the area. The departure was west of the accident site and near an almond orchard. As they were flying slowly over the north edge of the orchard the pilot initiated a descent, as well as slowing the helicopter to just above effective translational lift. He turned southbound and noted a 7- to 10-mile-per-hour (mph) tailwind. The pilot reported that the tailwind, coupled with the descent, caused the helicopter to enter a settling with power condition. He stated that due to the close proximity of the trees he was not able to perform a normal recovery of lowering of the collective and applying forward cyclic control. The helicopter descended between a row of trees and the main rotor blades struck the trees. The pilot stated that there were no mechanical malfunctions with the helicopter before the accident.

Flight

Event TypeAccident
Event Time10:00 PST
Nearest Airport0nm
Flight Plan FiledNone
Flight Plan ActivatedNo
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftHiller UH-12E
Tail NumberN236HA
Aircraft CategoryHeli
DamageSubstantial
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · VO-540 SERIES · Reciprocating · 310
Seats4

People & Injuries

Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 34 · Second Class · None

Conditions

ConditionsVMC
LightDaylight
Wind320° @ 9 kt
Visibility10 sm
CeilingNone
Temperature / Dew Point39 C / 30 C
Altimeter29.92 inHg
Observation Time17:53
Weather SourceWFAC

Appendix: Source Data