- Date
- June 16, 1991, 19:15 local (Jun 17, 1991, 00:15 UTC)
- Place
- Stoughton, WI
- Injuries
- 1 fatal
- Damage
- Destroyed
- Phase of flight
- Maneuvering
- Aircraft
- N8084DBowers Flybaby 1A
- Weather
- Visual (VMC) · Day
- Status
- Completed · report March 24, 1993
- Report
- Approved by Office Director
- FAA report
- 19910616021869A
- Case key
- 14842
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 inadequate design by the manufacturer to provide for adequate protection from moisture accumulation in the form of drain holes. Contributing factors were the deterioration (wood rot) of the wing spar attach and the lack of inspection access.
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 performing an aerobatic maneuver the right wing failed and departed the airplane. The airplane then descended into the terrain. Subsequent examination revealed wood rot at the fuselage carry thru spar attachment where the failure occurred. Examination revealed similar rot on the left side. There were no drain holes in the area of the spar attchment where moisture could accumulate. It was further determined that the area where the deterioration occurred was not visible during normal inspection.
Aircraft
- Registration
- N8084D
- Reported as
- Bowers Flybaby 1A
- Category
- Airplane, amateur-built
- Serial number
- 70-30
- Airframe hours
- 250
- Engine
- Continental C-85-12F, 85 horsepower, reciprocating
- Damage
- Destroyed
- Flight
- Personal · Part 91
- Operator
- James H. Otterback, doing business as Harold A. Otterback
- Registered owner
- James H. Otterback
- Airworthiness certificate
- Special, Experimental (Special)
- Last inspection
- Annual · April 4, 1991 · 8 hours before
- Departed
- 2W16 · Stoughton, WI
- Destination
- WI06 · Waunakee, WI
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
- 41
- Certificate
- Private
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Valid Medical--no waivers/lim.
- Seat
- Center
- Toxicology
- Performed
- Flight hours
- 642 total · 100 in this make and model
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 330° at 6 knots
- Visibility
- 20 statute miles
- Lowest ceiling
- None
- Observed at
- MSN, 10 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.