- Date
- October 14, 1982, 14:18 local (20:18 UTC)
- Place
- Cascade, ID
- Injuries
- 2 fatal
- Damage
- Destroyed
- Phase of flight
- Maneuvering
- Aircraft
- N6676DBoeing Vertol 107
- Weather
- Visual (VMC) · Day
- Status
- Completed · report October 14, 1983
- Report
- Approved by Office Director
- FAA report
- 19821014052839A
- Case key
- 70154
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
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
During a log slinging operation a loud bang was heard & the acft was observed to rapidly descend vertically to the ground with numerous small fragments falling in the same vicinity. The #5 synchronization shaft was found to be fractured at the forward end about 9 inches aft of the connection assy to the #4 shaft. This resulted in an out of synchronization condition between the forward & aft rotor blades as well as a loss of power to the forward rotor. A fatigue fracture originated in the aft most ring of rivet holes. The fatigue cracks propogated from multiple origins within those rivet holes where a "step" was found at the base of the hole & closest to the inside diameter of the shaft. All rivet holes in the forward end of the shaft had topographic features similar to those produced in a steel plate by deliberately drilling holes without complete penetrations.
Aircraft
- Registration
- N6676D
- Reported as
- Boeing Vertol 107
- Category
- Helicopter
- Serial number
- 6
- Airframe hours
- 2,343
- Engine
- GE CT-58-140, 1,500 horsepower, turbo shaft
- Damage
- Destroyed
- Flight
- Part 133
- Operator
- Columbia Helicopters, Inc.
- Registered owner
- Columbia Helicopters, Inc.
- Departed
- Cascade, ID
- Destination
- Cascade, ID
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
- 36
- Certificate
- Commercial
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Flight hours
- 6,800 total · 4,300 in this make and model · 303 in the last 90 days · 80 in the last 30 days · 6 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- Calm
- Visibility
- 30 statute miles
- Temperature
- 156 °F
- Altimeter
- 30.00 inHg
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 N6676D · 3
Matched to the same aircraft by N-number and date.