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NTSB Report
September 26, 1986 · Hughes 269B · N9427F
Baldwin, WI
Overview
Report Status
Preliminary report
Event Type
Accident
Date
September 26, 1986
Injury Outcomes
No injuries (2 uninjured)
Location
Baldwin, WI
Aircraft
Hughes 269B
Tail Number
N9427F
Operator
Dagnon Aviation
Injuries
None
Aircraft Damage
Substantial
NTSB Number
CHI86LA236
AFTER PICKING UP HIS PASSENGER AT WILLIAMS PIPELINE, MINNEAPOLIS, MINNESOTA, THE PLT FLEW EASTWARD ALONG INTERSTATE 90 ENROUTE TO A PIPELINE NEAR WAUSAU, WISCONSIN. WHILE FLYING AT APPROXIMATELLY 400 FEET, THE PLT AND PASSENGER STATED THAT THE ENGINE STARTED TO MAKE A GRINDING OR KNOCKING NOISE AND THAT THERE WAS AN ALMOST INSTANTANEOUS LOSS OF POWER. THE PLT THEN DROPPED THE COLLECTIVE AND TURNED APPROXIMATELY 40 DEGREES TO THE SANDY, UPWARD SLOPING GROUND. THE NOSE OF THE AIRCRAFT REMAINED LOW AND THE TAILBOOM RAISED. THE MAIN ROTOR BLADES THEN STRUCK THE TAILBOOM. WRECKAGE EXAMINATION REVEALED THAT THE NUMBER FOUR PISTON ROD PROTRUDED THROUGH THE ENGINE CASE, WHICH WAS CRACKED FROM THE HOLE TO THE NUMBER FOUR CYLINDER BASE.
Full Narrative
AFTER PICKING UP HIS PASSENGER AT WILLIAMS PIPELINE, MINNEAPOLIS, MINNESOTA, THE PLT FLEW EASTWARD ALONG INTERSTATE 90 ENROUTE TO A PIPELINE NEAR WAUSAU, WISCONSIN. WHILE FLYING AT APPROXIMATELLY 400 FEET, THE PLT AND PASSENGER STATED THAT THE ENGINE STARTED TO MAKE A GRINDING OR KNOCKING NOISE AND THAT THERE WAS AN ALMOST INSTANTANEOUS LOSS OF POWER. THE PLT THEN DROPPED THE COLLECTIVE AND TURNED APPROXIMATELY 40 DEGREES TO THE SANDY, UPWARD SLOPING GROUND. THE NOSE OF THE AIRCRAFT REMAINED LOW AND THE TAILBOOM RAISED. THE MAIN ROTOR BLADES THEN STRUCK THE TAILBOOM. WRECKAGE EXAMINATION REVEALED THAT THE NUMBER FOUR PISTON ROD PROTRUDED THROUGH THE ENGINE CASE, WHICH WAS CRACKED FROM THE HOLE TO THE NUMBER FOUR CYLINDER BASE.
Flight
Event TypeAccident
Event Time10:30 CDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftHughes 269B
Tail NumberN9427F
Aircraft CategoryHeli
DamageSubstantial
OperatorDagnon Aviation
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · HIO-360-AIA · Reciprocating · 180
Seats3
People & Injuries
Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 25 · First Class
Conditions
ConditionsVMC
LightDaylight
Wind220° @ 9 kt, gusting 11 kt
Visibility8 sm
CeilingNone
Altimeter0
Weather SourcePILO