- Date
- June 8, 1990, 06:30 local (13:30 UTC)
- Place
- Buttonwillow, CA
- Injuries
- 1 serious, 1 minor; on the ground: 1 minor
- Damage
- Destroyed
- Phase of flight
- Maneuvering
- Aircraft
- N6725KGrumman-Schweizer G-164B
- Weather
- Visual (VMC) · Day
- Status
- Completed · report September 4, 1992
- Report
- Approved by Office Director
- FAA report
- 19900608019559A
- Case key
- 26558
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
Failure of the #7 cylinder due to a pre-existing crack. The terrain condition was a related factor.
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
The pilot was completeing an aerial application swath run, when he heard a loud backfire emanate from the engine during the pull-up. The engine then quit running altogether. The pilot attempted to make a landing on a dirt road, but landed short in a tomato field, and the aircraft nosed over onto its back. Examination of the engine revealed that the number 7 cylinder head had a crack, which extended from the forward spark plug boss around the cylinder head to the rear spark plug boss. Detailed examination of the crack showed that the fracture face was contaminated by carbon deposits and light corrosion in the coarse area of the crack, indicating that the crack was present for a lengthy period of time prior to the accident. The cylinder was reported to have only 181 hours since overhaul.
Aircraft
- Registration
- N6725K
- Reported as
- Grumman-Schweizer G-164B
- Category
- Airplane
- Serial number
- 438B
- Airframe hours
- 4,894
- Engine
- P&W R-1340-AN-1, 600 horsepower, reciprocating
- Damage
- Destroyed
- Fire
- On-Ground
- Flight
- Aerial application · Part 137
- Operator
- Vince Crop Duster, Inc.
- Registered owner
- Vince Crop Dusters, Inc
- Airworthiness certificate
- Special, Restricted (Special)
- Last inspection
- Annual · April 17, 1990 · 165 hours before
- Departed
- NONE
- 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
- 55
- Certificate
- Commercial
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Center
- Flight hours
- 12,000 total · 3,000 in this make and model · 12,000 as pilot in command · 150 in the last 90 days · 75 in the last 30 days · 5 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 140° at 5 knots
- Visibility
- 20 statute miles
- Lowest ceiling
- None
- Temperature
- 70 °F, dew point 59 °F
- Altimeter
- 29.00 inHg
- Observed at
- BFL, 12 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 N6725K · 3
Matched to the same aircraft by N-number and date.