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NTSB Report
November 10, 1991 · Beech D18S · N4193
Hilo, HI
Overview
Report Status
Probable Cause
Event Type
Accident
Date
November 10, 1991
Injury Outcomes
No injuries (11 uninjured)
Location
Hilo, HI
Aircraft
Beech D18S
Tail Number
N4193
Operator
Tomy International
Injuries
None
Aircraft Damage
Substantial
NTSB Number
LAX92LA042
ABT 45 MI FM LNDG, THE L ENG RPM BGN TO FLUCTUATE, THEN AT ABT 15 MI FM LNDO, IT LOST POWER ALTOGETHER. THE PLT SAID THE ACFT WOULD NOT MAINT ALTITUDE. UNABLE TO RCH THE RWY, HE DITCHED THE ACFT IN HILO BAY ABT 1/4 MI FM SHORE & 1.5 MI FM THE ARPT. AFTER RETRIEVAL, THE ACFT & L ENG WERE EXAMINED. THE ACCESSORY GEAR DRIVE SHAFT WAS FND TO HAVE FAILED IN TORSIONAL OVERLOAD. ON THE INSIDE OF THE CASE, AN AREA OF GOUGING & ABRASION WAS FND DRCTLY IN FNT OF THE STARTER GEAR. (THE LEFT MAG, FUEL PUMP & PROP GOVERNOR WERE DRIVEN BY THE ACCESSORY DRIVE GEAR.) DEEP IMPRESSIONS WERE NOTED ON ABT 70% OF THE GEAR TEETH, WITH MTRL DISPLACEMENT & GOUGING EVIDENT. THERE WAS EVIDENCE THAT THE COLLECTOR DRIVE FLOATING GEAR MAY HAVE MOVED FORWARD & HAD CONTACTED THE ENG CASE. ALSO, THERE WAS EVIDENCE OF MECHANICAL INTERFERENCE WITHIN THE ACCESSORY DRIVE GEAR SYS. THE ACFT GROSS WT AT THE TIME OF THE ACDNT WAS ABOUT 9108 LBS.
NTSB Probable Cause
THE AIRCRAFT'S LACK OF SINGLE ENGINE PERFORMANCE TO MAINTAIN ALTITUDE AFTER THE ENGINE LOST POWER. FACTORS RELATED TO THE ACCIDENT WERE: DISPLACEMENT/MECHANICAL INTERFERENCE WITHIN THE ACCESSORY DRIVE GEAR SYSTEM OF THE LEFT ENGINE, FAILURE OF THE LEFT ENGINE ACCESSORY DRIVE GEAR SHAFT, AND THE FAA'S INADEQUATE CERTIFICATION/APPROVAL OF THE OPERATOR, IN ORDER TO ASSURE COMPLIANCE WITH 14 CFR 135 CONCERNING THE ENGINE-OUT CAPABILITY.
Full Narrative
ABT 45 MI FM LNDG, THE L ENG RPM BGN TO FLUCTUATE, THEN AT ABT 15 MI FM LNDO, IT LOST POWER ALTOGETHER. THE PLT SAID THE ACFT WOULD NOT MAINT ALTITUDE. UNABLE TO RCH THE RWY, HE DITCHED THE ACFT IN HILO BAY ABT 1/4 MI FM SHORE & 1.5 MI FM THE ARPT. AFTER RETRIEVAL, THE ACFT & L ENG WERE EXAMINED. THE ACCESSORY GEAR DRIVE SHAFT WAS FND TO HAVE FAILED IN TORSIONAL OVERLOAD. ON THE INSIDE OF THE CASE, AN AREA OF GOUGING & ABRASION WAS FND DRCTLY IN FNT OF THE STARTER GEAR. (THE LEFT MAG, FUEL PUMP & PROP GOVERNOR WERE DRIVEN BY THE ACCESSORY DRIVE GEAR.) DEEP IMPRESSIONS WERE NOTED ON ABT 70% OF THE GEAR TEETH, WITH MTRL DISPLACEMENT & GOUGING EVIDENT. THERE WAS EVIDENCE THAT THE COLLECTOR DRIVE FLOATING GEAR MAY HAVE MOVED FORWARD & HAD CONTACTED THE ENG CASE. ALSO, THERE WAS EVIDENCE OF MECHANICAL INTERFERENCE WITHIN THE ACCESSORY DRIVE GEAR SYS. THE ACFT GROSS WT AT THE TIME OF THE ACDNT WAS ABOUT 9108 LBS.
Flight
Event TypeAccident
Event Time08:50 HST
Nearest AirportHilo International (1nm W)
Runway8
Runway Length9800 ft
Runway Width150 ft
Flight Plan FiledVFR
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBeech D18S
Tail NumberN4193
Aircraft CategoryAir
DamageSubstantial
OperatorTomy International
Operating RulePart 135
Engines2
Engine TypeReciprocating
Engine DetailsP&W · R-985-AN14B · Reciprocating · 450
Seats11
People & Injuries
Injury SummaryNo injuries (11 uninjured)
Fatal0
Serious0
Minor0
Uninjured11
Total11
Crew 1Age 56 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind260° @ 10 kt
Visibility15 sm
CeilingBroken clouds 28000 ft
Temperature / Dew Point70 F
Altimeter30.00 inHg
Observation Time18:44
Weather SourceWFAC