- Date
- February 24, 1995, 17:15 local (Feb 25, 1995, 01:15 UTC)
- Place
- Spokane, WA
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N49335Pitts S-2B
- Weather
- Visual (VMC) · Day
- Status
- Completed · report September 24, 1995
- Report
- Approved by Office Director
- FAA report
- 19950224002639A
- Case key
- 42114
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
Fatigue failure of the crankshaft. Factors were the soft terrain and the pilot/owner's failure to conduct recurring crankshaft inspections recommended by the manufacturer.
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 of the aerobatic airplane was practicing an inverted flat spin when the propeller and crankshaft flange separated from the engine. The pilot recovered from the maneuver, then made a forced landing onto a 780 foot model airplane runway. The aircraft overran the end of the runway, then the main landing gear settled into soft soil and the aircraft nosed over. The pilot stated that he had not been conducting recurrent crankshaft flange inspections, as recommended by a manufacturer's service bulletin.
Factual narrative
On February 24, 1995, approximately 1715 Pacific standard time (PST), a Pitts S-2B, N49335, nosed over after making a forced landing about 10 miles northwest of Spokane, Washington. The commercial pilot, who was the sole occupant of the aircraft, was not injured, but the aircraft sustained substantial damage. The practice aerobatic flight, which departed Felts Field, Spokane, Washington at about 1630, was being operated in visual meteorological conditions. No flight plan had been filed, and there was no report of an ELT activation.
According to the pilot, while practicing an inverted flat spin, the propeller and crankshaft flange separated from the engine. He then recovered from the maneuver, and made a forced landing at a 780 foot model airplane runway. During the landing roll, the aircraft rolled beyond the end of the runway and the main gear settled into soft soil and the aircraft nosed over.
The pilot stated that he had not been conducting the recurring (each ten hours of operation) crankshaft inspections recommended by the manufacturer in Lycoming service bulletin number 482, which relates to crankshaft flange area cracking on this model engine when it is used for unlimited-style aerobatics, including inverted spins.
Aircraft
- Registration
- N49335
- Reported as
- Pitts S-2B
- Category
- Airplane
- Serial number
- 5102
- Airframe hours
- 708
- Engine
- Lycoming AEIO-540-D4A5, 260 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Registered owner
- Coombes, James A.
- Airworthiness certificate
- Special, Experimental (Special)
- Last inspection
- Annual · October 22, 1994 · 15 hours before
- Departed
- SFF · WA
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
- Multi-engine land, Single-engine land, Single-engine sea
- Instrument ratings
- Airplane
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Front
- Flight hours
- 2,723 total · 652 in this make and model · 2,608 as pilot in command · 13 in the last 90 days · 6 in the last 30 days · 2 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 210° at 5 knots
- Visibility
- 2,530 statute miles
- Lowest ceiling
- None
- Temperature
- 50 °F
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.