# NTSB ANC12CA077: Bell 206L-3, N363AL, Circle, AK, July 20, 2012 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: July 20, 2012, 13:45 local (21:45 UTC) - Place: Circle, AK - Coordinates: 65.946113, -143.972778 - Nearby events: https://openairdocs.org/map.md?lat=65.9461&lon=-143.9728&mi=10 - Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping) - Defining event: [Standing-engine(s) operating: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - Highest injury: No injuries - Injuries: 4 uninjured - Status: Completed, report October 9, 2012 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: FAA FSDO-01 - NTSB case key (mKey): 84392 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC12CA077 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/84392/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=84392 - Page: https://openairdocs.org/ntsb/ANC12CA077 ## Probable cause The pilot's selection of unsuitable terrain for landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Info processing/decision: identification/recognition](https://openairdocs.org/ntsb-findings/02041510): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [All aircraft, 559 cases](https://openairdocs.org/ntsb-findings/02041510/cases.md) - [Runway/land/takeoff/taxi surface](https://openairdocs.org/ntsb-findings/03023000): Environmental issues › Physical environment · Contributed to outcome; cases with it: [All aircraft, 253 cases](https://openairdocs.org/ntsb-findings/03023000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Standing-engine(s) operating: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Standing-engine(s) operating: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot elected to land the high skid, turbine-powered helicopter in a burned-out wooded area as part of a vegetation reclamation survey. The area he selected contained several rain-soaked, burned, and fallen birch trees and required that he land on the fallen trees with the helicopter's skids perpendicular to the trees. The operator reported that, after landing atop the uneven, fallen trees, the pilot retarded the engine throttle to flight idle to begin the mandatory 2 minute engine cool down procedure. The helicopter subsequently tipped backwards and slid to the left, and the tail rotor struck a log. The helicopter sustained substantial damage to the tail boom, tail rotor drive system, and tail rotor gearbox. The pilot said that there were no preimpact mechanical problems with the helicopter. ## Factual narrative The pilot elected to land a high skid, turbine-powered helicopter in a burned-out wooded area as part of a vegetation reclamation survey. The area he selected contained several rain-soaked, burned and fallen birch trees, which required that he land perpendicular to and on the fallen trees with the helicopter's skids. The operator reported that after landing atop the uneven, fallen trees, the pilot retarded the engine throttle to flight idle to begin the mandatory 2 minute engine cool down procedure. The helicopter subsequently tipped backwards and slid to the left, with the tail rotor striking a log. The pilot said there were no preimpact mechanical problems with the helicopter. The helicopter sustained substantial damage to the tail boom, tail rotor drive system, and tail rotor gearbox. ## Aircraft - Registration: N363AL (not matched to a registry record) - Reported make and model: BELL 206L-3 - Category: Helicopter - Serial number: 51472 - Airframe hours: 12617 - Engines: Rolls Royce C30P 650 horsepower turbo shaft - Damage: Substantial damage - Flight: Business, Part 135 - Operator: Bristow Alaska Inc, doing business as Bristow Alaska, Inc. - Registered owner: Bristow Alaska Inc - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, July 17, 2012 - Departed: MTF, Fairbanks, AK - Destination: Circle, AK - Flight plan: VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 61; injuries: none; airline transport; instrument ratings: helicopter; medical: class 2, with waivers/limitations; last flight review June 10, 2012; seat: right; flight hours: 6,338 total, 2,165 in this make and model, 94 in the last 90 days, 58 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: 2,500 ft broken - Temperature: 68 °F - Altimeter: 29.87 inHg - Observed at: CRC, 10 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 (OpenAirDocs). - [Accident 20120720015569A](https://openairdocs.org/incident/20120720015569A), Jul 20, 2012: Bell 206L-3, Circle, AK, Substantial damage. The pilot in-command elected to land in an area not suitable for touchdown and attempted to position the back of the skids on a log. After approximately two… ## Docket (2 files) The files NTSB released with the investigation on August 20, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=84392. 3.0 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 2.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40375563&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Helicopter Accident/Incident Supplemental Checklist (item 2, .PDF, 202 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40375564&FileExtension=.PDF&FileName=Helicopter%20Accident%2FIncident%20Supplemental%20Checklist-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.