# NTSB WPR26LA146: Bell Helicopter Textron 206L-1, N5017G, Chimney Rock, MT, April 4, 2026 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: April 4, 2026, 16:00 local (22:00 UTC) - Place: Chimney Rock, MT - Coordinates: 45.543896, -110.74795 - Nearby events: https://openairdocs.org/map.md?lat=45.5439&lon=-110.7480&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Dynamic rollover](https://openairdocs.org/ntsb-events/231) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report June 22, 2026 - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Western Pacific Region - Parties: FAA Helena FSDO - NTSB case key (mKey): 202757 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR26LA146 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/202757/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=202757 - Page: https://openairdocs.org/ntsb/WPR26LA146 ## Probable cause The pilot’s failure to maintain adequate clearance from the terrain while performing a low altitude circling takeoff maneuver, which resulted in a dynamic rollover. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Attention/monitoring: monitoring environment](https://openairdocs.org/ntsb-findings/02021545): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Bell Helicopter Textron 206L-1, 6 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=1182107), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Bell Helicopter Textron 206L-1, 8 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=1182107), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Terrain: sloped/uneven terrain](https://openairdocs.org/ntsb-findings/03021017): Environmental issues › Physical environment · Contributed to outcome (probable cause); cases with it: [Bell Helicopter Textron 206L-1, 1 case](https://openairdocs.org/ntsb-findings/03021017/cases.md?model=1182107), [All aircraft, 270 cases](https://openairdocs.org/ntsb-findings/03021017/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-low-alt flying: Low altitude operation/event](https://openairdocs.org/ntsb-events/220); cases with it: [Bell Helicopter Textron 206L-1, 4 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=1182107), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md) - [Takeoff: Dynamic rollover](https://openairdocs.org/ntsb-events/231) (defining event); cases with it: [Bell Helicopter Textron 206L-1, 3 cases](https://openairdocs.org/ntsb-events/231/sequence.md?model=1182107), [All aircraft, 161 cases](https://openairdocs.org/ntsb-events/231/sequence.md) ## Analysis The pilot and pilot-rated passenger were on a personal flight practicing off airport landings. After landing in an open meadow, the pilot elected to depart using a low altitude circling maneuver. The pilot stated the purpose of the maneuver was to gain effective translational lift. During the maneuver, as the helicopter accelerated, it began to descend, and the left skid contacted the terrain, resulting in a dynamic rollover. The helicopter sustained substantial damage to the fuselage, , main rotor system, tail rotor system, and empennage. The pilot stated that they received training in circling takeoff maneuvers during their commercial pilot training and had previously performed similar maneuvers. The pilot reported there were no pre-accident mechanical malfunctions or anomalies with the helicopter that would have precluded normal operation. ## Aircraft - Registration: [N5017G](https://openairdocs.org/aircraft/N5017G), registered now, S/N 45228, built 1979 (OpenAirDocs) - Reported make and model: BELL HELICOPTER TEXTRON 206L-1 - Registry model: [Bell Helicopter Textron 206L-1](https://openairdocs.org/model/bell-helicopter-textron-206l-1) (registry code 1182107) (OpenAirDocs) - Registry engine: [Allison 250-C28 series](https://openairdocs.org/engine/allison-250-c28-series) (registry code 03022, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 45228 - Year built: 1979 - Airframe hours: 19586.4 - Engines: Rolls Royce 250-C28B 435 horsepower turbo shaft - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Helimontana.Com LLC - Airworthiness certificate: Standard, Normal - Last inspection: Annual, February 10, 2026, 10 hours before - Departed: MT48, Livingston, MT - Destination: MT48, Livingston, MT - Airport: Mountain grassy meadow - Equipment: ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 21; injuries: none; commercial; instrument ratings: helicopter; medical: class 1, without waivers/limitations; last flight review November 2, 2026; seat: left; restraint: 4-point; flight hours: 264 total, 50 in this make and model, 231 as pilot in command, 4 in the last 90 days, 3 in the last 30 days, 1 in the last 24 hours - Pilot-rated passenger; age 58; injuries: none; private; medical: class 3, without waivers/limitations; seat: right; restraint: 4-point ## Weather - Conditions: Visual (VMC), Day - Wind: 270° at 17 knots, gusting 26 - Visibility: 10 statute miles - Temperature: 55 °F, dew point 27 °F - Altimeter: 30.28 inHg - Observed at: LVM, 16 nm away - METAR: METAR KLVM 042153Z AUTO 27017G26KT 10SM FEW065 13/M03 A3028 RMK AO2 PK WND 28028/2134 SLP253 T01281033 $ ## 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 20260404003829A](https://openairdocs.org/incident/20260404003829A), Apr 4, 2026: Bell Helicopter Textron 206L-1, Livingston, MT, Destroyed. Description of the deviation: While operating in VFR conditions, [privacy data omitted], [privacy data omitted] crashed in a small clearing approximately 18… ## Docket (4 files) The files NTSB released with the investigation on June 22, 2026, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=202757. 5.8 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=20224035&FileExtension=pdf&FileName=WPR26LA146%20-%206120.1%20-%20Pilot_Flat_Redacted-Rel.pdf - Memorandum for record a�� telephone interview, pilot (item 2, PDF, 2 pages, 100 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=20223607&FileExtension=pdf&FileName=WPR26LA146%20-%20ROC%20-%20Pilot_Redacted-Rel.pdf - Pilot's statement (item 3, PDF, 1 page, 123 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=20476244&FileExtension=pdf&FileName=WPR26LA146%20-%20Pilots%20written%20statement_Redacted-Rel.pdf - Photos (item 4, PDF, 4 pages, 3 photos, 3.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=20224182&FileExtension=pdf&FileName=WPR26LA146%20-%20Photo%20Array-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.