# NTSB CEN21LA432: Bell 206L-3, N170AM, Berlin, IL, July 9, 2021 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: July 9, 2021, 11:00 local (16:00 UTC) - Place: Berlin, IL - Coordinates: 39.764167, -89.982778 - Nearby events: https://openairdocs.org/map.md?lat=39.7642&lon=-89.9828&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-hover: Dynamic rollover](https://openairdocs.org/ntsb-events/231) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Central Region - Parties: FAA - NTSB case key (mKey): 103916 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN21LA432 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/103916/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=103916 - Page: https://openairdocs.org/ntsb/CEN21LA432 ## Probable cause The pilot’s failure to maintain control of the helicopter with a stuck skid, which resulted in a dynamic rollover. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: lateral/bank control](https://openairdocs.org/ntsb-findings/01062023): Aircraft › Aircraft oper/perf/capability · Not specified (probable cause); cases with it: [Bell 206L-3, 1 case](https://openairdocs.org/ntsb-findings/01062023/cases.md?model=1182108), [All aircraft, 390 cases](https://openairdocs.org/ntsb-findings/01062023/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 206L-3, 8 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=1182108), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-hover: Loss of control in flight](https://openairdocs.org/ntsb-events/240); cases with it: [Bell 206L-3, 8 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=1182108), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Maneuvering-hover: Dynamic rollover](https://openairdocs.org/ntsb-events/231) (defining event); cases with it: [Bell 206L-3, 2 cases](https://openairdocs.org/ntsb-events/231/sequence.md?model=1182108), [All aircraft, 161 cases](https://openairdocs.org/ntsb-events/231/sequence.md) ## Analysis The pilot reported that while landing the helicopter on a loading truck, he felt the skids settle and spread. After a few seconds, the helicopter began to slide off the truck. He increased collective in an attempt to move forward away from the truck, but thought that the skid was stuck. The pilot was able to dislodge the skid but the helicopter rolled onto its left side, resulting in substantial damage to the fuselage. The pilot reported no mechanical malfunctions or failures that would have precluded normal operation. ## Aircraft - Registration: [N170AM](https://openairdocs.org/aircraft/N170AM), registered now, S/N 51036, built 1982 (OpenAirDocs) - Reported make and model: BELL 206L-3 (NO SERIES) - Registry model: [Bell 206L-3](https://openairdocs.org/model/bell-206l-3) (registry code 1182108) (OpenAirDocs) - Registry engine: [Rolls-Royce 250-C30P](https://openairdocs.org/engine/rolls-royce-250-c30p) (registry code 54013, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 51036 - Year built: 1982 - Airframe hours: 12492.7 - Engines: ALLISON 250-C20B 650 horsepower turbo shaft - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: The Heli Team - Registered owner: Premier Rotors LLC - Airworthiness certificate: Special, Restricted (Special); Standard, Normal - Last inspection: 100 hour, June 3, 2021 - Destination: Same as departure - Airport: n/a - Equipment: ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 35; injuries: none; commercial; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review May 20, 2021; seat: right; restraint: 4-point; flight hours: 5,500 total, 550 in this make and model, 5,000 as pilot in command, 250 in the last 90 days, 50 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 90° at 3 knots - Visibility: 10 statute miles ## 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 20210709009039A](https://openairdocs.org/incident/20210709009039A), Jul 9, 2021: Bell 206L-3, Berlin, IL, Destroyed. The pilot of the helicopter had just finished a 14 CFR 137 aerial application and approached the re-supply truck; landing from the west (heading east). Upon… ## Docket (2 files) The files NTSB released with the investigation on October 14, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=103916. 2.0 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12808706&FileExtension=pdf&FileName=6120_Redacted-Rel.pdf - Photos (item 2, PDF, 2 pages, 599 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12764933&FileExtension=pdf&FileName=Photo%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.