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NTSB Report
July 24, 1991 · Waco KNF · NC698N
Wendover, UT
Overview
Report Status
Probable Cause
Event Type
Accident
Date
July 24, 1991
Injury Outcomes
No injuries (2 uninjured)
Location
Wendover, UT
Aircraft
Waco KNF
Tail Number
NC698N
Operator
William C Phelps
Injuries
None
Aircraft Damage
Substantial
NTSB Number
SEA91LA188
THE PILOT OF THE WACO KNF WAS UNABLE TO CONTROL HIS AIRCRAFT WHEN IT PULLED HARD TO THE RIGHT UPON LANDING. THE AIRCRAFT RAN OFF THE SIDE OF THE RUNWAY AND FLIPPED OVER IN THE SOFT DIRT. THE PILOT HAD ADDED AN UNAUTHORIZED O-RING ON TOP OF THE OLEO STRUT SEAL. HE SAID THAT THE SEAL WAS LEAKING AND HE WAS UNABLE TO FIND A REPLACEMENT IN THE LOCAL AREA, WHILE ON A CROSS-COUNTRY FLIGHT. AFTER DEPARTURE THE NEXT MORNING THE STRUT FAILED TO FULLY EXTEND, WHICH CAUSED THE AIRCRAFT TO BECOME DIFFICULT TO CONTROL UPON LANDING.
NTSB Probable Cause
PILOT INSTALLED AN IMPROPER 'O' RING WHICH RESTRICTED NORMAL LANDING GEAR EXTENSION AND SUBSEQUENT LOSS OF CONTROL BY THE PILOT.
Full Narrative
THE PILOT OF THE WACO KNF WAS UNABLE TO CONTROL HIS AIRCRAFT WHEN IT PULLED HARD TO THE RIGHT UPON LANDING. THE AIRCRAFT RAN OFF THE SIDE OF THE RUNWAY AND FLIPPED OVER IN THE SOFT DIRT. THE PILOT HAD ADDED AN UNAUTHORIZED O-RING ON TOP OF THE OLEO STRUT SEAL. HE SAID THAT THE SEAL WAS LEAKING AND HE WAS UNABLE TO FIND A REPLACEMENT IN THE LOCAL AREA, WHILE ON A CROSS-COUNTRY FLIGHT. AFTER DEPARTURE THE NEXT MORNING THE STRUT FAILED TO FULLY EXTEND, WHICH CAUSED THE AIRCRAFT TO BECOME DIFFICULT TO CONTROL UPON LANDING.
Flight
Event TypeAccident
Event Time08:15 MDT
Nearest AirportWendover Field (0nm N)
Runway12
Runway Length8000 ft
Runway Width150 ft
Flight Plan FiledVFR
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftWaco KNF
Tail NumberNC698N
Aircraft CategoryAir
DamageSubstantial
OperatorWilliam C Phelps
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsKinner · K-5 · Reciprocating · 100
Seats2
People & Injuries
Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 63 · Third Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility50 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourcePILO