- Date
- August 9, 1992, 11:30 local (15:30 UTC)
- Place
- Cobb, GA
- Injuries
- 1 minor
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N4650WWeatherly 620A
- Weather
- Visual (VMC) · Day
- Status
- Completed · report July 29, 1993
- Report
- Approved by Office Director
- FAA report
- 19920809033189A
- Case key
- 8641
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
The corroded, and separated, magnetic chip detector plug which allowed the loss of all engine oil and the engine's subsequent seizure. Factors were the inadequate 100 hour inspection, and the high vegetation in the forced landing field.
Sequence of events
NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.
Analysis
While conducting an aerial application flight, the engine seized & a forced landing was made into a corn field. The airplane nosed over during the landing roll. Examination of the airplane revealed that engine oil covered its belly. The chip detector in the oil sump of the engine was found broken, with the detector electrode held on by its transmission wire. The open detector port had allowed all of the engine oil to escape. Metallurgical examination of the detector electrode revealed that it had separated because of corrosion. The operator's mechanic stated that he usually found about one tablespoon of water in the engine sump during 100 hour oil changes.
Aircraft
- Registration
- N4650W
- Reported as
- Weatherly 620A
- Category
- Airplane
- Serial number
- 1539
- Airframe hours
- 300
- Engine
- P&W R-985, 450 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Aerial application · Part 137
- Operator
- Varner Bass Aviation, Inc
- Registered owner
- Varner Bass Aviation, Inc
- Airworthiness certificate
- Special, Restricted (Special)
- Last inspection
- 100 hour · July 11, 1992 · 100 hours before
- Departed
- NONE · Leesburg, GA
- Destination
- NONE
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 42
- Certificate
- Commercial
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Center
- Flight hours
- 3,900 total · 500 in this make and model
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 330° at 3 knots
- Visibility
- 7 statute miles
- Lowest ceiling
- 10,000 ft broken
- Temperature
- 84 °F, dew point 72 °F
- Altimeter
- 30.00 inHg
- Observed at
- ABY, 15 nm away
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.
Other investigations on N4650W · 1
Matched to the same aircraft by N-number and date.