- Date
- August 31, 2012, 18:10 local (Sep 1, 2012, 02:10 UTC)
- Place
- Talkeetna, AK
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Standing
- Aircraft
- N178CHAerospatiale AS350 B2
- Defining event
- Standing-engine(s) operating: Miscellaneous/other
- Weather
- Visual (VMC) · Day
- Status
- Completed · report December 19, 2012
- Report
- Approved by Office Director
- NTSB office
- Alaska Regional Office
- Parties
- Federal Aviation Administration
- FAA report
- 20120831018509A
- Case key
- 84925
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 entanglement of a plastic tarp in the helicopter’s tail rotor after becoming dislodged from its securement.
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 pilot landed a high-skid, turbine-powered helicopter at a remote construction site, which contained several bags of cement that were covered by a plastic tarp. The plastic tarp was secured by a nylon strap that was wrapped around the bags. The pilot reported that after landing near the bags of cement, he retarded the engine throttle to flight idle to begin the mandatory 2-minute engine cool down procedure. During the engine cool down, the pilot felt an abrupt airframe vibration, so he immediately closed the engine throttle and performed an emergency engine shutdown. A postflight inspection revealed that the plastic tarp had dislodged from the nylon strap, and it subsequently became entangled in the tail rotor hub and blade assembly. As a result, the helicopter sustained substantial damage to the tail rotor drive system and tailboom. The pilot said there were no preaccident mechanical anomalies with the helicopter that would have precluded normal operation.
Factual narrative
The pilot landed a high skid, turbine-powered helicopter at a remote construction site, which contained several bags of cement that were covered by a plastic tarp. The plastic tarp was secured by a nylon strap that was wrapped around the bags. The pilot reported that after landing near the bags of cement, he retarded the engine throttle to flight idle to begin the mandatory 2-minute engine cool down procedure. During the engine cool down the pilot felt an abrupt airframe vibration, so he immediately closed the engine throttle, and did an emergency engine shutdown. A postflight inspection revealed that the plastic tarp had dislodged from the nylon strap, and it subsequently became entangled in the tail rotor hub and blade assembly. As a result, the helicopter sustained substantial damage to the tail rotor drive system and tail boom. The pilot said there were no preaccident mechanical problems with the helicopter.
Aircraft
- Registration
- N178CH
- Reported as
- Aerospatiale AS350 B2
- Category
- Helicopter
- Serial number
- 2042
- Airframe hours
- 8,741
- Engine
- Turbomeca Arriel, 731 horsepower, turbo shaft
- Damage
- Substantial damage
- Flight
- External load · Part 133
- Operator
- Last Frontier Air Venture
- Registered owner
- Bell Leasing LLC
- Airworthiness certificate
- Standard, Normal
- Last inspection
- 100 hour · August 23, 2012
- Departed
- Talkeetna, AK
- Destination
- Talkeetna, AK
- Flight plan
- Company VFR
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 64
- Injuries
- None
- Certificate
- Commercial
- Airplane ratings
- Single-engine sea, Multi-engine sea, Single-engine land, Multi-engine land
- Instrument ratings
- Airplane, Helicopter
- Medical
- Class 1, With waivers/limitations
- Seat
- Right
- Flight hours
- 14,000 total · 1,000 in this make and model
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- Variable at 10 knots
- Visibility
- 30 statute miles
- Lowest ceiling
- 6,000 ft overcast
- Temperature
- 50 °F
Docket · 1
The files NTSB released with the investigation on October 27, 2012, on NTSB’s docket system: statements, records, photos and specialists’ reports. 808 KB 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.