- Date
- November 10, 1989, 14:39 local (22:39 UTC)
- Place
- Chino, CA
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Approach
- Aircraft
- N6324XBell-Kitz Kopters 47D1
- Weather
- Visual (VMC) · Day
- Status
- Completed · report January 23, 1992
- Report
- Approved by Office Director
- FAA report
- 19891110044899A
- Case key
- 26682
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
A fatigue failure of both the main rotor stabilizer bar tube and the tie rod. In addition, the tie rod nut was loose and did not conform to engineering drawing specifications. Company personnel failed to detect the fatigue cracks during daily inspections.
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 student pilot was practicing touch and go takeoffs and landings. While on the downwind leg the student pilot rptd that the helicopter began to vibrate and then violently pitched up. The student pilot immediately executed an autorotation into a cow pasture. The wreckage exam dsclsd the main rotor stabilizer bar separated in flt and it was not found. The attach section of the bar remained connected at its attach points. Metallurgical exam dsclsd the inner bar and the tie rod fractured in fatigue which had propagated very slowly, and cracks would have been evident. Bell helicopter had issued service bulletin 47-(04-2)73-1 requiring daily inspection of the bar for cracks. The tie rod nut was a bogus part and excessively worn.
Aircraft
- Registration
- N6324X
- Reported as
- Bell-Kitz Kopters 47D1
- Category
- Helicopter
- Serial number
- T-610
- Engine
- Franklin 6V4, 200 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Operator
- Petkow, Raymond, doing business as Meadowlark Aviation
- Registered owner
- Raymond Petkow
- Airworthiness certificate
- Standard, Normal
- Departed
- CNO
- Destination
- CNO
- Airport
- CNO · Chino
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 28
- Certificate
- Student
- Medical
- Class 3, Valid Medical--no waivers/lim.
- Seat
- Left
- Flight hours
- 40 total · 40 in this make and model
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- Calm
- Visibility
- 30 statute miles
- Lowest ceiling
- None
- Altimeter
- 29.00 inHg
- Observed at
- CNO
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.