- Date
- December 16, 1991, 16:10 local (21:10 UTC)
- Place
- Wilksville, OH
- Injuries
- 1 minor
- Damage
- Substantial damage
- Phase of flight
- Enroute
- Aircraft
- N9601Devenport EAA Biplane
- Weather
- Visual (VMC) · Day
- Status
- Completed · report April 23, 1993
- Report
- Approved by Office Director
- FAA report
- 19911216056379A
- Case key
- 37028
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 restricted visibility of the pilot due to oil on the windshield and his goggles, which resulted in a tree strike and uncontrolled touchdown, during the execution of a precautionary landing. Factors related to the accident were a clogged crankcase breather tube, the lack of a whistle slot on the crankcase breather tube, and the trees.
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 in cruise flight, in an experimentally certified airplane, when the crankcase breather which was not pressurized with a whistle slot froze up. The crankcase pressurized and the crankcase seal was dislodged. The pilot made a precautionary landing in a field of limited size, surrounded by trees. Due to the restricted viibility of the pilot, with oil on his goggles and windshield, he struck a tree on final and made an uncontrolled touchdown in the field. The investigation revealed there is a requirement of a whistle slot on normal, utility, acrobatic, and commuter category airplanes, however, this requirement does not exist for experimental category airplanes.
Aircraft
- Registration
- N9601
- Reported as
- Devenport EAA Biplane (EAA BIPLAN)
- Category
- Airplane, amateur-built
- Serial number
- 1
- Airframe hours
- 185
- Engine
- Lycoming O-290-D, 70 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Operator
- Jack F. Holgate
- Registered owner
- Jack F. Holgate
- Airworthiness certificate
- Special, Experimental (Special)
- Last inspection
- Annual · June 24, 1991 · 70 hours before
- Departed
- LOZ · London, KY
- Destination
- UNI · Athens, OH
- Flight plan
- VFR
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
- 50
- Certificate
- Private
- Airplane ratings
- Single-engine land
- Medical
- Class 3, Valid Medical--w/ waivers/lim
- Flight hours
- 189.5 total · 36 in this make and model · 151 as pilot in command · 36.7 in the last 90 days · 14.1 in the last 30 days · 3.2 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- Variable at 8 knots
- Visibility
- 15 statute miles
- Lowest ceiling
- 1,000 ft overcast
- Temperature
- 36 °F
- Observed at
- HTS, 50 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.