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NTSB Report
November 21, 1991 · Bell 206BIII · N5011K
Davis, CA
Overview
Report Status
Probable Cause
Event Type
Accident
Date
November 21, 1991
Injury Outcomes
3 injuries (3 fatalities)
Location
Davis, CA
Aircraft
Bell 206BIII
Tail Number
N5011K
Operator
Aris Helicopter
Injuries
Fatal
Aircraft Damage
Destroyed
NTSB Number
LAX92FA047
A BELL HELICOPTER 206B III COLLIDED WITH LEVEL TERRAIN DURING NIGHT INSTRUMENT METEOROLOGICAL CONDITIONS. THE PILOT CONTACTED AIR TRAFFIC CONTROL TWENTY MILES SOUTHEAST OF HIS DESTINATION REPORTING INSTRUMENT METEOROLOGICAL CONDITIONS WITH LOW VISIBILITY IN LIGHT RAIN SHOWERS. THE PILOT WAS UNABLE TO MAINTAIN VFR CONDITIONS AND STARTED TO MANEUVER AROUND THE WEATHER. A WITNESS REPORTED SEEING THE HELICOPTER FLYING NORTH, AT AN ALTITUDE BELOW THE LEVEL OF AN INTERSTATE HIGHWAY. THE HELICOPTER HAD TO CLIMB TO CROSS THE INTERSTATE. THE HELICOPTER THEN DESCENDED, IMPACTED THE GROUND, AND DISINTEGRATED. ATC REPORTED LOST RADAR CONTACT WITH THE HELICOPTER. THE SEARCH FOR THE HELICOPTER WAS IMPEDED BY LOCAL DARKNESS AND GROUND FOG. THE PILOT'S DESTINATION AIRPORT LOCATED EIGHT NAUTICAL MILES NORTH OF THE ACCIDENT SITE WAS REPORTING A TEMPERATURE DEWPOINT SPREAD OF THREE DEGREES AND CALM WINDS.
NTSB Probable Cause
THE DECISION OF THE PILOT TO CONTINUE NIGHT LOW LEVEL FLIGHT IN FORECASTED ADVERSE WEATHER CONDITIONS. CONTRIBUTING TO THE ACCIDENT WAS THE FOGGY WEATHER AND DARK NIGHT CONDITIONS WHICH RESTRICTED THE PILOT'S VISUAL OUTLOOK.
Full Narrative
A BELL HELICOPTER 206B III COLLIDED WITH LEVEL TERRAIN DURING NIGHT INSTRUMENT METEOROLOGICAL CONDITIONS. THE PILOT CONTACTED AIR TRAFFIC CONTROL TWENTY MILES SOUTHEAST OF HIS DESTINATION REPORTING INSTRUMENT METEOROLOGICAL CONDITIONS WITH LOW VISIBILITY IN LIGHT RAIN SHOWERS. THE PILOT WAS UNABLE TO MAINTAIN VFR CONDITIONS AND STARTED TO MANEUVER AROUND THE WEATHER. A WITNESS REPORTED SEEING THE HELICOPTER FLYING NORTH, AT AN ALTITUDE BELOW THE LEVEL OF AN INTERSTATE HIGHWAY. THE HELICOPTER HAD TO CLIMB TO CROSS THE INTERSTATE. THE HELICOPTER THEN DESCENDED, IMPACTED THE GROUND, AND DISINTEGRATED. ATC REPORTED LOST RADAR CONTACT WITH THE HELICOPTER. THE SEARCH FOR THE HELICOPTER WAS IMPEDED BY LOCAL DARKNESS AND GROUND FOG. THE PILOT'S DESTINATION AIRPORT LOCATED EIGHT NAUTICAL MILES NORTH OF THE ACCIDENT SITE WAS REPORTING A TEMPERATURE DEWPOINT SPREAD OF THREE DEGREES AND CALM WINDS.
Flight
Event TypeAccident
Event Time18:14 PST
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBell 206BIII
Tail NumberN5011K
Aircraft CategoryHeli
DamageDestroyed
OperatorAris Helicopter
Operating RulePart 135
Engines1
Engine TypeTurboshaft
Engine DetailsAllison · 250-C20B · Turboshaft · 420
Seats5
People & Injuries
Injury Summary3 injuries (3 fatalities)
Fatal3
Serious0
Minor0
Uninjured0
Total3
Crew 1Age 35 · Second Class
Conditions
ConditionsIMC
LightDark Night
WindCalm
Visibility10 sm
CeilingOvercast 2300 ft
Temperature / Dew Point55 / 52
Altimeter30.00 inHg
Observation Time01:46
Weather SourceWFAC