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NTSB Report
November 20, 1991 · Cessna 172N · N80893
Boulder, CO
Overview
Report Status
Probable Cause
Event Type
Accident
Date
November 20, 1991
Injury Outcomes
No injuries (1 uninjured)
Location
Boulder, CO
Aircraft
Cessna 172N
Tail Number
N80893
Operator
Dakota Ridge Aviation
Injuries
None
Aircraft Damage
Substantial
NTSB Number
DEN92LA009
WITH THE EXCEPTION OF THE FIRST RUNWAY TURNOFF, ALL RUNWAY TURNOFFS WERE SUPPOSED TO BE BARRICADED CLOSED FOR TAXIWAY MAINTENANCE. THE PILOT LANDED BUT WAS UNABLE TO EXIT AT THE FIRST TURNOFF. THE SECOND TURNOFF WAS BARRICADED CLOSED. THE PILOT TAXIED TO THE END OF THE RUNWAY AND FOUND THIS TURNOFF WAS NOT BARRICADED. IT SHOULD HAVE BEEN. THE PILOT TAXIED BACK TOWARDS BACK OF THE AREA OF THE FIRST TURNOFF, HE FOUND THE TAXIWAY WAS BARRICADED. HE SAW A SMALL DIRT ROAD EXITING THE TAXIWAY AND THOUGHT IT WAS A TEMPORARY TAXIWAY ERECTED BY THE MAINTENANCE CREW. WHILE TAXIING TOWARDS THE RAMP ON THIS ROAD, THE AIRPLANE'S RIGHT WING STRUCK A SIGN. THE AIRPLANE SPUN AROUND AND THE TAIL STRUCK A BARBED WIRE FENCE.
NTSB Probable Cause
FAILURE OF THE PILOT TO MAINTAIN CLEARANCE FROM THE SIGN.
Full Narrative
WITH THE EXCEPTION OF THE FIRST RUNWAY TURNOFF, ALL RUNWAY TURNOFFS WERE SUPPOSED TO BE BARRICADED CLOSED FOR TAXIWAY MAINTENANCE. THE PILOT LANDED BUT WAS UNABLE TO EXIT AT THE FIRST TURNOFF. THE SECOND TURNOFF WAS BARRICADED CLOSED. THE PILOT TAXIED TO THE END OF THE RUNWAY AND FOUND THIS TURNOFF WAS NOT BARRICADED. IT SHOULD HAVE BEEN. THE PILOT TAXIED BACK TOWARDS BACK OF THE AREA OF THE FIRST TURNOFF, HE FOUND THE TAXIWAY WAS BARRICADED. HE SAW A SMALL DIRT ROAD EXITING THE TAXIWAY AND THOUGHT IT WAS A TEMPORARY TAXIWAY ERECTED BY THE MAINTENANCE CREW. WHILE TAXIING TOWARDS THE RAMP ON THIS ROAD, THE AIRPLANE'S RIGHT WING STRUCK A SIGN. THE AIRPLANE SPUN AROUND AND THE TAIL STRUCK A BARBED WIRE FENCE.
Flight
Event TypeAccident
Event Time10:10 MST
Nearest AirportBoulder Municipal (0nm N)
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftCessna 172N
Tail NumberN80893
Aircraft CategoryAir
DamageSubstantial
OperatorDakota Ridge Aviation
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-320-H2AD · Reciprocating · 160
Seats4
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 25 · Third Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility50 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourceWIT