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NTSB Report
July 22, 1989 · Cessna R172K · N736DA
Wisconsin Dells, WI
Overview
Report Status
Probable Cause
Event Type
Accident
Date
July 22, 1989
Injury Outcomes
No injuries (1 uninjured)
Location
Wisconsin Dells, WI
Aircraft
Cessna R172K
Tail Number
N736DA
Operator
Robert B Toenjes
Injuries
None
Aircraft Damage
Substantial
NTSB Number
CHI89LA141
WHILE EN ROUTE, THE PLT HEARD A 'MUFFLED POP' FROM THE ENG. APRX 30 SEC LATER, HE NOTICED SMOKE ENTERING THE COCKPIT & SOME POWER LOSS. OIL PRESSURE WAS OBSERVED GOING TO ZERO. THE PLT SHUT OFF THE FUEL & MADE AN EMERG LANDING. DRG THE LANDING, THE LEFT WING STRUCK A TREE & THE ACFT WAS DAMAGED. A POST-ACDNT INSPN REVEALED THE OIL FILLER CAP WAS LOOSE & HANGING FROM ITS CHAIN. A TEARDOWN INSPN OF THE ENG REVEALED NO EVIDENCE OF MECHANICAL DEFECTS WHICH WOULD HAVE ACCOUNTED FOR THE OIL LOSS.
NTSB Probable Cause
FAILURE OF THE PILOT TO INSURE THE OIL FILLER CAP WAS PROPERLY SECURED WHEN HE SERVICED THE AIRCRAFT BEFORE TAKEOFF, AND SUBSEQUENT LOSS OF OIL AND OIL EXHAUSTION. THE TREE WAS CONSIDERED TO BE A CONTRIBUTING FACTOR.
Full Narrative
WHILE EN ROUTE, THE PLT HEARD A 'MUFFLED POP' FROM THE ENG. APRX 30 SEC LATER, HE NOTICED SMOKE ENTERING THE COCKPIT & SOME POWER LOSS. OIL PRESSURE WAS OBSERVED GOING TO ZERO. THE PLT SHUT OFF THE FUEL & MADE AN EMERG LANDING. DRG THE LANDING, THE LEFT WING STRUCK A TREE & THE ACFT WAS DAMAGED. A POST-ACDNT INSPN REVEALED THE OIL FILLER CAP WAS LOOSE & HANGING FROM ITS CHAIN. A TEARDOWN INSPN OF THE ENG REVEALED NO EVIDENCE OF MECHANICAL DEFECTS WHICH WOULD HAVE ACCOUNTED FOR THE OIL LOSS.
Flight
Event TypeAccident
Event Time12:15 CDT
Nearest Airport0nm N
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftCessna R172K
Tail NumberN736DA
Aircraft CategoryAir
DamageSubstantial
OperatorRobert B Toenjes
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsContinental · IO-360-K · Reciprocating · 195
Seats4
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 59 · Third Class
Conditions
ConditionsVMC
LightDaylight
Wind60° @ 10 kt
Visibility5 sm
CeilingOvercast 2200 ft
Temperature / Dew Point0 C / 0 C
Altimeter30.00 inHg
Weather SourcePILO