- Date
- July 13, 2009, 10:15 local (17:15 UTC)
- Place
- Marysville, CA
- Injuries
- 3 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N244HPRobinson Helicopter R44
- Defining event
- Maneuvering-low-alt flying: Low altitude operation/event
- Weather
- Visual (VMC) · Day
- Status
- Completed · report September 30, 2009
- Report
- Approved by Office Director
- NTSB office
- Western Pacific Region
- Parties
- Federal Aviation Administration FSDO
- FAA report
- 20090713013479A
- Case key
- 74265
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 pilot’s failure to maintain adequate clearance from the power line wires.
Findings · 2
NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.
Sequence of events
The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.
Analysis
The private pilot reported that he was flying the helicopter about 500 feet above the ground and decided to descend to follow a riverbed. While descending to the river, one of the passengers alerted him to the presence of power line wires that obstructed their flight path. The pilot applied full aft cyclic and collective in an attempt to avoid colliding with the wires; however, the tail boom and tail rotor contacted the wires. The impact resulted in the separation of the tail rotor blades and the bottom section of the vertical stabilizer from the helicopter. Following the collision the pilot initiated an autorotation. Upon touchdown, the helicopter bounced and when it touched down again, it was moving sideways to the left and rolled over. The helicopter came to rest on the bank of the river on its left side. Examination of the helicopter revealed substantial damage to the main rotor assembly, the tail rotor assembly, vertical stabilizer, tail boom, and fuselage. The pilot reported that there were no mechanical anomalies with the helicopter prior to the accident.
Factual narrative
The private pilot reported that he was flying the helicopter about 500 feet above the ground and decided to descend to follow a riverbed. While descending to the river, one of the passengers alerted him to the presence of power line wires that obstructed their flight path. The pilot applied full aft cyclic and collective in an attempt to avoid colliding with the wires; however, the tail boom and tail rotor contacted the wires. The impact resulted in the separation of the tail rotor blades and the bottom section of the vertical stabilizer from the helicopter. Following the collision the pilot initiated an autorotation. Upon touchdown, the helicopter bounced and when it touched down again, it was moving sideways to the left and rolled over. The helicopter came to rest on the bank of the river on its left side. Examination of the helicopter revealed substantial damage to the main rotor assembly, the tail rotor assembly, vertical stabilizer, tail boom, and fuselage. The pilot reported that there were no mechanical anomalies with the helicopter prior to the accident.
Aircraft
- Registration
- N244HP
- Reported as
- Robinson Helicopter R44
- Category
- Helicopter
- Serial number
- 0427
- Airframe hours
- 1,106
- Engine
- Lycoming O-540-F1B5, 260 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Operator
- Dwelle David W
- Registered owner
- Dwelle David W
- Airworthiness certificate
- Standard, Normal
- Departed
- AUN · Auburn, CA
- Destination
- KAUN · Auburn, CA
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
- 61
- Injuries
- None
- Certificate
- Private
- Airplane ratings
- Single-engine land
- Medical
- Class 3, With waivers/limitations
- Last flight review
- March 15, 2009
- Seat
- Right
- Flight hours
- 1,250 total · 105 in this make and model · 30 in the last 90 days · 8 in the last 30 days · 0 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 330° at 12 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 79 °F, dew point 45 °F
- Altimeter
- 30.01 inHg
- Observed at
- MYV, 8 nm away
Docket · 1
The files NTSB released with the investigation on July 24, 2009, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.1 MB in all.
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.