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NTSB Report
July 1, 1991 · Bell 206BIII · N302MH
Sheep Mountain, AK
Overview
Report Status
Probable Cause
Event Type
Accident
Date
July 1, 1991
Injury Outcomes
No injuries (3 uninjured)
Location
Sheep Mountain, AK
Aircraft
Bell 206BIII
Tail Number
N302MH
Operator
Maritime Helicopters
Injuries
None
Aircraft Damage
Substantial
NTSB Number
ANC91LA085
THE PILOT ATTEMPTED TO LAND ON THE 6,000 FOOT RIDGE AND MADE A GO AROUND. HE MADE A SECOND ATTEMPT WITH THE WIND AS A RIGHT QUARTERING HEADWIND. THE PILOT STATED THE WIND WAS VARIABLE AND GUSTY. DURING HIS SECOND APPROACH AND APPROXIMATELY 8 TO 10 FEET ABOVE THE LANDING AREA, HE LOST TAIL ROTOR AUTHORITY AND ELECTED TO LAND IMMEDIATELY UPON THE ONLY AVAILABLE LANDING SURFACE. THE TERRAIN SLOPED AWAY AT A CONSIDERABLE ANGLE AND HE WAS AFRAID OF ROLLING THE HELICOPTER. AN OPERATION SAFETY NOTICE ISSUED BY BELL HELICOPTER OUTLINING THE CONDITIONS FOR LOSS OF TAIL ROTOR AUTHORITY WAS AVAILABLE TO THE PILOT IN THE COMPANY READING FILE. THE READING FILE IS REQUIRED TO BE READ AND INITIALED BY ALL COMPANY PILOTS.
NTSB Probable Cause
THE PILOT'S LACK OF COMPENSATION FOR WIND CONDITIONS AND CONTINUED OPERATION WITH THE WIND IN THE 'CRITICAL WIND AZIMUTH' AREA WHICH LED TO LIMITED TAIL ROTOR AUTHORITY. CONTRIBUTING TO THE ACCIDENT WAS THE VARIABLE AND GUSTY WIND CONDITIONS.
Full Narrative
THE PILOT ATTEMPTED TO LAND ON THE 6,000 FOOT RIDGE AND MADE A GO AROUND. HE MADE A SECOND ATTEMPT WITH THE WIND AS A RIGHT QUARTERING HEADWIND. THE PILOT STATED THE WIND WAS VARIABLE AND GUSTY. DURING HIS SECOND APPROACH AND APPROXIMATELY 8 TO 10 FEET ABOVE THE LANDING AREA, HE LOST TAIL ROTOR AUTHORITY AND ELECTED TO LAND IMMEDIATELY UPON THE ONLY AVAILABLE LANDING SURFACE. THE TERRAIN SLOPED AWAY AT A CONSIDERABLE ANGLE AND HE WAS AFRAID OF ROLLING THE HELICOPTER. AN OPERATION SAFETY NOTICE ISSUED BY BELL HELICOPTER OUTLINING THE CONDITIONS FOR LOSS OF TAIL ROTOR AUTHORITY WAS AVAILABLE TO THE PILOT IN THE COMPANY READING FILE. THE READING FILE IS REQUIRED TO BE READ AND INITIALED BY ALL COMPANY PILOTS.
Flight
Event TypeAccident
Event Time13:30 AKDT
Nearest Airport0nm
Runway0
Flight Plan FiledVFR
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBell 206BIII
Tail NumberN302MH
Aircraft CategoryHeli
DamageSubstantial
OperatorMaritime Helicopters
Operating RulePart 135
Engines1
Engine TypeTurboshaft
Engine DetailsAllison · 250-C20B · Turboshaft · 420
Seats5
People & Injuries
Injury SummaryNo injuries (3 uninjured)
Fatal0
Serious0
Minor0
Uninjured3
Total3
Crew 1Age 54 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind5 kt, gusting 10 kt
Visibility20 sm
CeilingNone
Temperature / Dew Point54 / 0 C
Altimeter0
Weather SourcePILO