- Date
- August 12, 2017, 11:00 local (16:00 UTC)
- Place
- Bowling Green, KY
- Injuries
- 1 minor
- Damage
- Substantial damage
- Phase of flight
- Initial climb
- Aircraft
- N8262Charles D Walker Walker Curtiss JN4D
- Defining event
- Initial climb: Loss of control in flight
- Weather
- Visual (VMC) · Day
- Status
- Completed · report December 15, 2017
- Report
- Approved by Office Director
- NTSB office
- General Aviation Accidents
- Parties
- FAA
- FAA report
- 20170812013359A
- Case key
- 95820
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 pilot’s exceedance of the biplane’s critical angle of attack during initial climb, which resulted in an aerodynamic stall and collision with trees.
Findings · 3
NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.
Sequence of events
The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.
Analysis
The pilot of the experimental, amateur-built biplane reported that, following a normal initial climb, about 100 ft above the ground, the biplane started an uncommanded left turn, followed by a descent. He added that it became apparent that the flightpath was into the tree line, and he "attempted to climb to possibly maintain at least an altitude to clear the trees, but to no avail, nearly stalling." Subsequently, the biplane impacted the trees. The biplane sustained substantial damage to the wings and fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the biplane that would have precluded normal operation. The pilot added that the biplane is "not very stable once in a flying configuration, any air mass (gusts) change can disturb the balance and result in self-induced turns, climbs and descents. These movements have to be countered immediately because of the relative size (small) of control surfaces (rudder, ailerons). And corrections are slow, possibly resulting in loss of altitude. Pilots expect these upsets and become alert for them." The automated weather observation system on the accident airport reported, about the time of the accident, the wind was from 360° at 5 knots. The pilot was departing from runway 03. The calculated density altitude was 1,897 ft.
Factual narrative
The pilot of the experimental, amateur-built, biplane reported that, following a normal initial climb, about 100 ft. above the ground, the biplane started an un-commanded turn to the left, followed by a descent. He added that, it became apparent that the flight path was into the tree line, and he "attempted to climb to possibly maintain at least an altitude to clear the trees, but to no avail, nearly stalling." Subsequently, the biplane impacted the trees. The biplane sustained substantial damage to the wings and fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the biplane that would have precluded normal operation. The pilot added that, the biplane is "not very stable once in a flying configuration, any air mass (gusts) change can disturb the balance and result in self-induced turns, climbs and descents. These movements have to be countered immediately because of the relative size (small) of control surfaces (rudder, ailerons). And corrections are slow, possibly resulting in loss of altitude. Pilots expect these upsets and become alert for them." The automated weather observation system on the accident airport reported, about the time of the accident, the wind was 360° at 5 knots. The pilot was departing on runway 03. The calculated density altitude was 1,897 ft.
Aircraft
- Registration
- N8262
- Reported as
- Charles D Walker Walker Curtiss JN4D (NO SERIES)
- Category
- Airplane, amateur-built
- Serial number
- WC001
- Built
- 2013
- Airframe hours
- 330
- Engine
- 150 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Airworthiness certificate
- Special, Experimental (Special)
- Last inspection
- Annual · April 1, 2017
- Departed
- BWG · Bowling Green, KY
- Destination
- BWG · Bowling Green, KY
- Airport
- BWG · Bowling Green-Warren County Rg, runway 03, 6,501 × 150 ft, asphalt
- Equipment
- 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
- 75
- Injuries
- Minor
- Certificates
- Flight instructor, Airline transport
- Airplane ratings
- Single-engine sea, Single-engine land, Multi-engine land
- Medical
- BasicMed
- Last flight review
- February 17, 2017
- Seat
- Rear
- Restraint
- 3-point
- Flight hours
- 20,000 total · 60 in this make and model · 17,000 as pilot in command · 25 in the last 90 days · 15 in the last 30 days · 5 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 360° at 5 knots
- Visibility
- 9 statute miles
- Lowest ceiling
- 5,000 ft broken
- Temperature
- 79 °F, dew point 73 °F
- Altimeter
- 30.00 inHg
- Observed at
- KBWG
Docket · 2
The files NTSB released with the investigation on October 23, 2017, on NTSB’s docket system: statements, records, photos and specialists’ reports. 966 KB in all.
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 N8262 · 1
Matched to the same aircraft by N-number and date.