# NTSB ANC25LA097: Airbus Helicopters AS350B3e, N589SH, Skwentna, AK, August 20, 2025 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: August 20, 2025, 14:30 local (22:30 UTC) - Place: Skwentna, AK - Coordinates: 61.769167, -152.98693 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=61.7692&lon=-152.9869&mi=10 - Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping) - Defining event: [Standing-engine(s) operating: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report October 23, 2025 - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration (FAA) - NTSB case key (mKey): 200883 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC25LA097 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/200883/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=200883 - Page: https://openairdocs.org/ntsb/ANC25LA097 ## Probable cause The pilot’s inadvertent entanglement of a lightweight Kevlar long line into the helicopters operating main rotor system, resulting in a severe imbalance and separation of the main rotor gearbox. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Eurocopter AS 350 B3, 4 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md?model=8680954), [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md) - [Terrain: rough terrain](https://openairdocs.org/ntsb-findings/03021015): Environmental issues › Physical environment · Effect on operation; cases with it: [Eurocopter AS 350 B3, 1 case](https://openairdocs.org/ntsb-findings/03021015/cases.md?model=8680954), [All aircraft, 442 cases](https://openairdocs.org/ntsb-findings/03021015/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: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) (defining event); cases with it: [Eurocopter AS 350 B3, 6 cases](https://openairdocs.org/ntsb-events/900/sequence.md?model=8680954), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) ## Analysis The operator reported that the helicopter was being used to sling construction equipment to a remote mine site located in an area of steep mountainous terrain. After the pilot placed the external load at a prearranged site next to the drill pad, he maneuvered the helicopter to a landing site in an area of rock-covered terrain to disconnect and stow the lightweight Kevlar long line that was still attached to the helicopter’s cargo hook. After a successful landing, the pilot reduced the engine throttle to ground idle, locked the flight controls, then exited the helicopter with the engine and rotor still operating. As the pilot coiled the Kevlar long line into the helicopter, a portion of the line became entangled in the rock covered terrain, and the pilot pulled hard to free it. As the Kevlar long line suddenly released from the rocks, the recoiling line became entangled in the operating main rotor blades which resulted in a severe main rotor imbalance. As a result, the main rotor gearbox and entire main rotor system were subsequently ripped from the helicopter. The helicopter sustained substantial damage to the fuselage, tail boom assembly, and main rotor drive system. The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation. ## Aircraft - Registration: [N589SH](https://openairdocs.org/aircraft/N589SH), registered now, S/N 7745 (OpenAirDocs) - Reported make and model: AIRBUS HELICOPTERS AS350B3e - Registry model: [Eurocopter AS 350 B3](https://openairdocs.org/model/eurocopter-as-350-b3) (registry code 8680954) (OpenAirDocs) - Category: Helicopter - Serial number: 7745 - Year built: 2013 - Airframe hours: 5664.5 - Engines: SAFRAN ARRIEL 2D turbo shaft - Damage: Substantial damage - Flight: External load, Part 133 - Operator: Soloy Helicopters LLC - Registered owner: Csc Delaware Trust Co Trustee - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, August 9, 2025, 5 hours before - Destination: Same as departure - Flight plan: Company VFR - Equipment: Video recording device, Satellite tracking device, ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 58; injuries: none; commercial; medical: class 2, with waivers/limitations; last flight review March 25, 2025; seat: none; flight hours: 15,500 total, 9,900 in this make and model, 15,400 as pilot in command, 290 in the last 90 days, 50 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 25 statute miles - Temperature: 55 °F, dew point 52 °F - Altimeter: 30.12 inHg - Observed at: APT, 21 nm away - METAR: PAPT 201857Z COR 00000KT 25SM FEW027 13/11 A3012 RMK NO SPECI ## 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 20250820017389A](https://openairdocs.org/incident/20250820017389A), Aug 20, 2025: Eurocopter AS 350 B3, Skwetna, AK, Substantial damage. After landing the helicopter, the pilot exited the aircraft and left it in ground idle to retrieve the long line that had just been used. While standing on the… ## Docket (2 files) The files NTSB released with the investigation on October 23, 2025, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=200883. 3.1 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 10 pages, 1.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19461997&FileExtension=pdf&FileName=Point%20One%20097%20Master_Redacted-Rel.pdf - Photos (item 2, PDF, 3 pages, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19411472&FileExtension=pdf&FileName=Photos-Rel.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.