- Date
- October 12, 1993, 16:45 local (20:45 UTC)
- Place
- Coldwater, MI
- Injuries
- 2 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N7032UHughes 269A
- Weather
- Visual (VMC) · Day
- Status
- Completed · report October 20, 1994
- Report
- Approved by Office Director
- FAA report
- 19931012038699A
- Case key
- 9412
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 fatigue failure of the tailboom support strut attachment lug.
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 certificated helicopter pilot who was receiving dual instruction was at the controls in a hover. The pilot and the CFI both reported hearing a bang followed by loss of directional control. The student pilot made a successful hovering autorotation. The investigation revealed the tailboom support strut attachment lug had failed at the left aft cluster fitting. The failed part was examined and found to have failed due to fatigue.
Factual narrative
On October 12, 1993, at 1645 eastern daylight time, a Hughes 269A, N7032U, operated by Brooks Aero, Inc., Marshall, Michigan, sustained substantial damage when it had an in-flight structural failure, while in a hover at the Branch County Airport, Coldwater, Michigan. Neither the certified flight instructor, nor the private certificated student pilot were injured. The instructional flight originated at Brooks Field, Marshall, Michigan. No flight plan was filed, and visual meteorological conditions prevailed at the time.
The investigation found the left tailboom support strut attachment lug on the left aft cluster fitting (P/N 269A2234) had failed. A witness reported the tailboom was moving up and down just before the accident. The tailboom was hit and severed by the main rotor system. The dual student, who was at the controls, made a successful hovering autorotative landing without additional damage to the helicopter.
The helicopter log book shows the last inspection was a 100 hour inspection performed on June 22, 1993. The helicopter has logged 65 hours since the inspection. The log book entry records compliance with Airworthiness Directives 88-17-04 and 76-18-01 which pertain to the cluster fittings.
The failed support strut attachment lug was sent to the NTSB Materials Laboratory, Washington, D.C., for examination. The laboratory reported the presence of fatigue fracture features on both ears of the attachment lug.
Aircraft
- Registration
- N7032U
- Reported as
- Hughes 269A
- Category
- Helicopter
- Serial number
- 114-0327
- Airframe hours
- 4,695
- Engine
- Lycoming HIO-360-B1A, 180 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Instructional · Part 91
- Operator
- Brooks Aero, Inc.
- Registered owner
- Shallow Corp.
- Airworthiness certificate
- Standard, Normal
- Last inspection
- 100 hour · June 22, 1993 · 65 hours before
- Departed
- 5D8 · Marshall, MI
- Airport
- D96 · Branch County Memorial
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
- 25
- Certificates
- Flight instructor, Airline transport, Commercial
- Instrument ratings
- Helicopter
- Medical
- Class 2, Valid Medical--no waivers/lim.
- Seat
- Left
- Flight hours
- 1,750 total · 1,500 as pilot in command · 240 in the last 90 days · 40 in the last 30 days · 6 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 300° at 10 knots
- Visibility
- 12 statute miles
- Lowest ceiling
- 2,900 ft broken
- Temperature
- 68 °F, dew point 54 °F
- Altimeter
- 29.00 inHg
- Observed at
- BTL, 24 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.