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NTSB Report
February 8, 1989 · Piper PA-18-150 · N4355Z
Boulder, CO
Overview
Report Status
Probable Cause
Event Type
Accident
Date
February 8, 1989
Injury Outcomes
No injuries (2 uninjured)
Location
Boulder, CO
Aircraft
Piper PA-18-150
Tail Number
N4355Z
Operator
Boulder Flying Service
Injuries
None
Aircraft Damage
Substantial
NTSB Number
DEN89LA074
THE ATP RATED CFI WAS PERFORMING A RENTAL CHECKOUT WITH A PRIVATE PLT. THE CHECK PLT TOLD THE PLT TO MAKE A LANDING AND 'IF SUFFICIENT RUNWAY REMAINED,' TO MAKE ANOTHER TAKEOFF. A LANDING WAS COMPLETED ON RWY 8R, A 4,100 X 75 FT ASPHALT RWY. THE CHECK PILOT HAD BEEN FOLLOWING THROUGH ON THE CONTROLS BUT DURING THE LANDING ROLL HE RELEASED THE CONTROLS AND WAITED FOR THE PLT TO STOP. HE SAID THAT AS SOON AS HE REMOVED HIS HANDS FROM THE CONTROLS, THE STICK WENT FORWARD AND HE HEARD THE ENGINE SPEED UP. THE AIRPLANE SWERVED TO THE LEFT. THE CHECK PLT TOOK THE CONTROLS AND ATTEMPTED TO CORRECT THE SWERVE, TO NO AVAIL. THE PLANE STRUCK A SNOW DRIFT ON THE LEFT SIDE OF THE RWY AND NOSED OVER.
NTSB Probable Cause
FAILURE OF THE DUAL STUDENT TO MAINTAIN DIRECTIONAL CONTROL AND THE FAILURE OF THE PILOT IN COMMAND (CFI), TO PROVIDE ADEQUATE REMEDIAL ACTION IN A TIMELY MANNER, TO CORRECT THE SWERVE. A SECOND PROBABLE CAUSE WAS THE CFI'S FAILURE TO PROVIDE ADEQUATE SUPERVISION DURING THE LANDING ROLL. INADEQUATE CREW COORDINATION IS CONSIDERED A FACTOR.
Full Narrative
THE ATP RATED CFI WAS PERFORMING A RENTAL CHECKOUT WITH A PRIVATE PLT. THE CHECK PLT TOLD THE PLT TO MAKE A LANDING AND 'IF SUFFICIENT RUNWAY REMAINED,' TO MAKE ANOTHER TAKEOFF. A LANDING WAS COMPLETED ON RWY 8R, A 4,100 X 75 FT ASPHALT RWY. THE CHECK PILOT HAD BEEN FOLLOWING THROUGH ON THE CONTROLS BUT DURING THE LANDING ROLL HE RELEASED THE CONTROLS AND WAITED FOR THE PLT TO STOP. HE SAID THAT AS SOON AS HE REMOVED HIS HANDS FROM THE CONTROLS, THE STICK WENT FORWARD AND HE HEARD THE ENGINE SPEED UP. THE AIRPLANE SWERVED TO THE LEFT. THE CHECK PLT TOOK THE CONTROLS AND ATTEMPTED TO CORRECT THE SWERVE, TO NO AVAIL. THE PLANE STRUCK A SNOW DRIFT ON THE LEFT SIDE OF THE RWY AND NOSED OVER.
Flight
Event TypeAccident
Event Time14:10 MST
Nearest AirportBoulder Municipal (0nm N)
Runway0
Runway Length4100 ft
Runway Width75 ft
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftPiper PA-18-150
Tail NumberN4355Z
Aircraft CategoryAir
DamageSubstantial
OperatorBoulder Flying Service
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-320-A2B · Reciprocating · 150
Seats2
People & Injuries
Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 34 · Second Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility50 sm
CeilingNone
Temperature / Dew Point18 C / 0 C
Altimeter0
Weather SourcePILO