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NTSB Report
October 5, 1991 · Bentley Mongoose A · N7143K
Boulder City, NV
Overview
Report Status
Probable Cause
Event Type
Accident
Date
October 5, 1991
Injury Outcomes
2 injuries (2 fatalities)
Location
Boulder City, NV
Aircraft
Bentley Mongoose A
Tail Number
N7143K
Operator
Bentley Richard F
Injuries
Fatal
Aircraft Damage
Destroyed
NTSB Number
LAX92LA006
THE PLT'S MED CERT WAS EXPIRED & HE DID NOT HOLD A ROTORCRAFT CATEGORY RATING. DRG AN EXAM OF THE WRECKAGE, STRONG ROTATIONAL SIGNATURES WERE EVIDENT ON BOTH THE PROP & MAIN ROTOR BLADES. NO ACFT SYS ABNORMALITIES WERE FND DRG THE EXAM OF THE WRECKAGE. WHEEL TRACKS & IMPACT GND SCARS WERE FND ON THE DRY LAKE BED SURFACE. THREE TIRE TRACKS MATCHING THE DIMENSIONAL GEOMETRY OF THE LNDG GEAR WERE FND EXTENDING FOR A DISTANCE OF ABOUT 150 YDS. AN ADDITIONAL 15 YDS OF MAIN GEAR ONLY TRACKS WERE FND, WHICH TERMINATED AT A BERM. HVY GOUGE MARKS WERE NOTED ON THE TOP OF THE BERM, WHICH MATCHED ALL 3 LNDG GEAR. ABOUT 105 YDS BEYOND THE BERM, A GND IMPACT CRATER WAS OBSERVED, FOLLOWED BY A DISTURBANCE IN THE DIRT WHICH CULMINATED IN THE GYROCOPTER WRECKAGE. THE GYROCOPTER HAD NOT BEEN ISSUED AN AIRWORTHINESS CERTIFICATE IN ANY CATEGORY.
NTSB Probable Cause
THE PILOT'S SELECTION OF AN INADEQUATE TAKEOFF AREA WHICH WAS TOO SHORT FOR THE PREVAILING CONDITIONS.
Full Narrative
THE PLT'S MED CERT WAS EXPIRED & HE DID NOT HOLD A ROTORCRAFT CATEGORY RATING. DRG AN EXAM OF THE WRECKAGE, STRONG ROTATIONAL SIGNATURES WERE EVIDENT ON BOTH THE PROP & MAIN ROTOR BLADES. NO ACFT SYS ABNORMALITIES WERE FND DRG THE EXAM OF THE WRECKAGE. WHEEL TRACKS & IMPACT GND SCARS WERE FND ON THE DRY LAKE BED SURFACE. THREE TIRE TRACKS MATCHING THE DIMENSIONAL GEOMETRY OF THE LNDG GEAR WERE FND EXTENDING FOR A DISTANCE OF ABOUT 150 YDS. AN ADDITIONAL 15 YDS OF MAIN GEAR ONLY TRACKS WERE FND, WHICH TERMINATED AT A BERM. HVY GOUGE MARKS WERE NOTED ON THE TOP OF THE BERM, WHICH MATCHED ALL 3 LNDG GEAR. ABOUT 105 YDS BEYOND THE BERM, A GND IMPACT CRATER WAS OBSERVED, FOLLOWED BY A DISTURBANCE IN THE DIRT WHICH CULMINATED IN THE GYROCOPTER WRECKAGE. THE GYROCOPTER HAD NOT BEEN ISSUED AN AIRWORTHINESS CERTIFICATE IN ANY CATEGORY.
Flight
Event TypeAccident
Event Time14:48 PDT
Nearest AirportDRYLAKE (0nm)
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBentley Mongoose A
Tail NumberN7143K
Aircraft CategoryGyro
DamageDestroyed
OperatorBentley Richard F
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsRotax · 582 · Reciprocating · 65
Seats2
People & Injuries
Injury Summary2 injuries (2 fatalities)
Fatal2
Serious0
Minor0
Uninjured0
Total2
Crew 1Age 35 · Third Class
Conditions
ConditionsVMC
LightDaylight
Wind50° @ 5 kt
Visibility50 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourceWIT