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NTSB Report
August 12, 1982 · Hiller UH12L4 · N3748Z
Wisconsin Dells, WI
Overview
Report Status
Preliminary report
Event Type
Accident
Date
August 12, 1982
Injury Outcomes
2 injuries (1 serious injury, 1 minor injury), 1 uninjured
Location
Wisconsin Dells, WI
Aircraft
Hiller UH12L4
Tail Number
N3748Z
Operator
Nelsonind
Injuries
Serious
Aircraft Damage
Substantial
NTSB Number
CHI82FA304
DURING CLIMB, AT ABOUT 200 FT AGL, THE M/R LOST RPM. DURING AUTOROTATION THE ENG RPM INCREASED BEYOND THE RED LINE WHEN THE PLT ADDED POWER. THE HELICOPTER MADE A HARD LANDING IN A RESIDENTIAL AREA. INSPECTION OF THE MERCURY CLUTCH REVEALED THAT THE EXTERIOR SURFACE OF THE CLUTCH DRUM EXHIBITED EVIDENCE OF EXCESSIVE OVERHEATING. THE INSIDE SURFACE OF THE DRUM SHOWED SEVERE GLAZING & DISCOLORATION IN THE CLUTCH SHOE WEAR AREA. THERE WERE ALSO SEVERAL CRACKS IN THE CLUTCH DRUM. THE HOUSING BEARING JOURNAL HAD EXPERIENCED SEVERE PITTING. THERE WAS ALSO SEVERE WEAR IN THE BEARING JOURNAL AREA. THE CLUTCH SHOES SHOWED SIGNIFICANT GLAZING & SURFACE CRACKING, & WERE SEVERELY WORN.
Full Narrative
DURING CLIMB, AT ABOUT 200 FT AGL, THE M/R LOST RPM. DURING AUTOROTATION THE ENG RPM INCREASED BEYOND THE RED LINE WHEN THE PLT ADDED POWER. THE HELICOPTER MADE A HARD LANDING IN A RESIDENTIAL AREA. INSPECTION OF THE MERCURY CLUTCH REVEALED THAT THE EXTERIOR SURFACE OF THE CLUTCH DRUM EXHIBITED EVIDENCE OF EXCESSIVE OVERHEATING. THE INSIDE SURFACE OF THE DRUM SHOWED SEVERE GLAZING & DISCOLORATION IN THE CLUTCH SHOE WEAR AREA. THERE WERE ALSO SEVERAL CRACKS IN THE CLUTCH DRUM. THE HOUSING BEARING JOURNAL HAD EXPERIENCED SEVERE PITTING. THERE WAS ALSO SEVERE WEAR IN THE BEARING JOURNAL AREA. THE CLUTCH SHOES SHOWED SIGNIFICANT GLAZING & SURFACE CRACKING, & WERE SEVERELY WORN.
Flight
Event TypeAccident
Event Time14:40 CDT
Nearest Airport0nm N
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftHiller UH12L4
Tail NumberN3748Z
Aircraft CategoryHeli
DamageSubstantial
OperatorNelsonind
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · VO-540-2CA · Reciprocating · 250
Seats3
People & Injuries
Injury Summary2 injuries (1 serious injury, 1 minor injury), 1 uninjured
Fatal0
Serious1
Minor1
Uninjured1
Total3
Crew 1Age 25 · Second Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility25 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0