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NTSB Report
September 3, 1991 · Cessna 208 · N9438F
Dillingham, AK
Overview
Report Status
Probable Cause
Event Type
Accident
Date
September 3, 1991
Injury Outcomes
No injuries (1 uninjured)
Location
Dillingham, AK
Aircraft
Cessna 208
Tail Number
N9438F
Operator
Markair Express
Injuries
None
Aircraft Damage
Substantial
NTSB Number
ANC91FA142
The pilot in command performed a preflight and checked the oil by removing the dip stick/oil filler cap. After 10 to 15 minutes of flight time, the pilot noticed a decrease in the torque indication and engine oil pressure. He elected to return to Dillingham and enroute the engine lost more oil pressure and 'coughed' twice. The pilot feathered the propeller and landed on the tundra. Upon landing the airplane nosed over. The on site inspection showed that the left, lower side of the fuselage was covered with oil and the oil dip stick/filler cap was not installed in the filler neck. It was resting on the inside of the upper cowling because the airplane was upside down. The brief shows that the pilot was the holder of an airline transport pilot certificate because the computer database program will not accept a commercial pilot rating while showing a scheduled 14 CFR 135, passenger/cargo type of operation. The pilot is only the holder of a commercial pilot certificate.
NTSB Probable Cause
THE PILOT'S INATTENTIVE PREFLIGHT INSPECTION WHICH RESULTED IN HIS FAILURE TO PROPERLY SECURE THE ENGINE OIL TUBE FILLER CAP RESULTING IN THE LOSS OF ENGINE OIL AND OIL PRESSURE AND THE PILOT'S FAILURE TO PROPERLY COMPENSATE FOR WIND CONDITIONS DURING THE FORCED LANDING. CONTRIBUTING TO THE ACCIDENT WAS THE ENGINE FAILURE AND SUBSEQUENT FORCED LANDING ON SOFT TERRAIN.
Full Narrative
THE PILOT IN COMMAND PERFORMED A PREFLIGHT AND CHECKED THE OIL BY REMOVING THE DIP STICK/OIL FILLER CAP. AFTER 10 TO 15 MINUTES OF FLIGHT TIME, THE PILOT NOTICED A DECREASE IN THE TORQUE INDICATION AND ENGINE OIL PRESSURE. HE ELECTED TO RETURN TO DILLINGHAM AND ENROUTE THE ENGINE LOST MORE OIL PRESSURE AND 'COUGHED' TWICE AND THE PILOT FEATHERED THE PROPELLER AND LANDED ON THE TUNDRA. UPON LANDING THE AIRPLANE NOSED OVER. THE ON SITE INSPECTION SHOWED THAT THE LEFT, LOWER SIDE OF THE FUSELAGE WAS COVERED WITH OIL AND THE OIL DIP STICK/FILLER CAP WAS NOT INSTALLED IN THE FILLER NECK. IT WAS RESTING ON THE INSIDE OF THE UPPER COWLING BECAUSE THE AIRPLANE WAS UPSIDE DOWN. THE BRIEF SHOWS THAT THE PILOT WAS THE HOLDER OF AN AIRLINE TRANSPORT PILOT CERTIFICATE BECAUSE THE COMPUTER DATABASE PROGRAM WILL NOT ACCEPT A COMMERCIAL PILOT RATING WHILE SHOWING A SCHEDULED 14 CFR 135, PASSENGER/CARGO TYPE OF OPERATION. THE PILOT IS ONLY THE HOLDER OF A COMMERCIAL PILOT CERTIFICATE.
Flight
Event TypeAccident
Event Time09:53 AKDT
Nearest Airport0nm
Runway0
Flight Plan FiledCvfr
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftCessna 208
Tail NumberN9438F
Aircraft CategoryAir
DamageSubstantial
OperatorMarkair Express
Operating RulePart 135
Engines1
Engine TypeTurboprop
Engine DetailsP&W · PT6A-114 · Turboprop · 600
People & Injuries
Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 29 · Second Class
Conditions
ConditionsVMC
LightDaylight
Wind360° @ 10 kt
Visibility40 sm
CeilingOvercast 5000 ft
Temperature / Dew Point45 C / 0 C
Altimeter0
Weather SourcePILO