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NTSB Report
July 29, 1992 · Bell 47J2 · N8476E
Adjuntas, PR
Overview
Report Status
Probable Cause
Event Type
Accident
Date
July 29, 1992
Injury Outcomes
4 injuries (4 fatalities)
Location
Adjuntas, PR
Aircraft
Bell 47J2
Tail Number
N8476E
Operator
Western Helicopters
Injuries
Fatal
Aircraft Damage
Destroyed
NTSB Number
MIA92FA156
Witnesses observed the helicopter, and then a loud bang was heard & the engine was no longer audible. The helicopter immediately made a turn to the left & descended. As it approached the ground, the engine noise increased. The helicopter impacted hard on top of a hill. Post-crash examination indicated that the engine and transmission oil tank and engine oil system contained 2 qts of oil. The turn-to-lock type oil stick was not locked, and oil residue was visible exiting the filler neck and flowing out of the engine compartment and down the tail boom. No oil leakage was found on the ground at the crash site. The day before the accident, an FAA inspector had noted oil leakage in and around the helicopter's engine compartment. Toxicology tests results on the pilot was positive for 0.010 ug/ml (blood-tetrahydrocannabinol carboxylic acid) marijuana, one passenger was positive for 0.038 ug/ml (blood) marijuana, and another passenger was positive for 2.4 mcg/ml (urine) diphenhydramine or Benadryl.
NTSB Probable Cause
THE FAILURE OF THE PILOT-IN-COMMAND TO MAINTAIN ADEQUATE ROTOR RPM DURING A PRECAUTIONARY LANDING FOLLOWING THE LOSS OF ENGINE OIL. IN ADDITION, THE PILOT FAILED TO INSURE THAT THE ENGINE CONTAINED ADEQUATE OIL, AND THAT THE OIL DIP STICK WAS SECURE PRIOR TO TAKEOFF. A FACTOR WHICH CONTRIBUTED TO THE ACCIDENT WAS THE PILOT'S IMPAIRMENT DUE TO MARIJUANA.
Full Narrative
WITNESSES OBSERVED THE HELICOPTER, AND THEN A LOUD BANG WAS HEARD & THE ENGINE WAS NO LONGER AUDIBLE. THE HELICOPTER IMMEDIATELY MADE A TURN TO THE LEFT & DESCENDED. AS IT APPROACHED THE GROUND, THE ENGINE NOISE INCREASED. THE HELICOPTER IMPACTED HARD ON TOP OF A HILL. POST-CRASH EXAMINATION INDICATED THAT THE ENGINE AND TRANSMISSION OIL TANK AND ENGINE OIL SYSTEM CONTAINED 2 QTS OF OIL. THE TURN-TO-LOCK TYPE OIL STICK WAS NOT LOCKED, AND OIL RESIDUE WAS VISIBLE EXITING THE FILLER NECK AND FLOWING OUT OF THE ENGINE COMPARTMENT AND DOWN THE TAIL BOOM. NO OIL LEAKAGE WAS FOUND ON THE GROUND AT THE CRASH SITE. THE DAY BEFORE THE ACCIDENT, AN FAA INSPECTOR HAD NOTED OIL LEAKAGE IN AND AROUND THE HELICOPTER'S ENGINE COMPARTMENT. TOXICOLOGY TESTS RESULTS ON THE PILOT WAS POSITIVE FOR FOR 0.010 UG/ML (BLOOD-TETRAHYDROCANNABINOL CARBOXYLIC ACID) MARIJUANA, ONE PASSENGER WAS POSITIVE FOR 0.038 UG/ML (BLOOD) MARIJUANA, AND ANOTHER PASSENGER WAS POSITIVE FOR 2.4 MCG/ML (URINE) DIPHENHYDRAMINE OR BENADRYL.
Flight
Event TypeAccident
Event Time08:30 AST
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireGrd
Aircraft ExplosionNo
Aircraft
AircraftBell 47J2
Tail NumberN8476E
Aircraft CategoryHeli
DamageDestroyed
OperatorWestern Helicopters
Operating RulePart 135
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · VO-540-B1B3 · Reciprocating · 305
Seats4
People & Injuries
Injury Summary4 injuries (4 fatalities)
Fatal4
Serious0
Minor0
Uninjured0
Total4
Crew 1Age 33 · First Class
Conditions
ConditionsVMC
LightDaylight
Wind100° @ 7 kt
Visibility15 sm
CeilingNone
Altimeter30.00 inHg
Observation Time12:46
Weather SourceWFAC