# NTSB ERA21LA040: Bell 206, N123NC, Raleigh, NC, November 8, 2020 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: November 8, 2020, 14:15 local (19:15 UTC) - Place: Raleigh, NC - Coordinates: 35.732111, -78.628722 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.7321&lon=-78.6287&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach: Settling with power/vortex ring state](https://openairdocs.org/ntsb-events/244) - 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: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 102253 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA21LA040 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/102253/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=102253 - Page: https://openairdocs.org/ntsb/ERA21LA040 ## Probable cause The pilot's loss of helicopter control after entry into vortex ring state, which resulted in main rotor blade contact with the tailboom, and impact with the ground. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Bell 206A, 3 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=1181508), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Performance/control parameters: descent/approach/glide path](https://openairdocs.org/ntsb-findings/01062040): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Bell 206A, 2 cases](https://openairdocs.org/ntsb-findings/01062040/cases.md?model=1181508), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/01062040/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach: Settling with power/vortex ring state](https://openairdocs.org/ntsb-events/244) (defining event); cases with it: [Bell 206A, 1 case](https://openairdocs.org/ntsb-events/244/sequence.md?model=1181508), [All aircraft, 52 cases](https://openairdocs.org/ntsb-events/244/sequence.md) - [Approach: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Bell 206A, 3 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1181508), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Landing-flare/touchdown: Hard landing](https://openairdocs.org/ntsb-events/092); cases with it: [Bell 206A, 2 cases](https://openairdocs.org/ntsb-events/092/sequence.md?model=1181508), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) ## Analysis After flying for about 1.5 hours on a training flight, the pilot of the helicopter returned to the operator’s hangar and aborted two approaches after encountering vortex ring state. He decided to land at a nearby facility to have the occupant disembark to reduce the gross weight of the helicopter, and to improve the power available margin. He departed and attempted a third approach to the hangar. At about 300 ft agl, the helicopter again encountered vortex ring state; however, there was not enough altitude to successfully complete the same recovery maneuver. The helicopter began losing altitude rapidly and while descending it impacted the tops of several trees. A main rotor blade then contacted the tail rotor drive shaft, which immediately resulted in a surge of the engine, followed by a yaw of the helicopter to the right. The pilot then conducted an autorotative landing into the middle of a nearby road. The helicopter’s tailboom, main rotor, and fuselage were substantially damaged during the accident sequence. The pilot reported that there were no preimpact mechanical malfunctions or failures of the helicopter that would have precluded normal operation. ## Aircraft - Registration: [N123NC](https://openairdocs.org/aircraft/N123NC), registered now, S/N 610, built 1971 (OpenAirDocs) - Reported make and model: BELL 206 (A) - Registry model: [Bell 206A](https://openairdocs.org/model/bell-206a) (registry code 1181508) (OpenAirDocs) - Registry engine: [Allison 250 SER 250HP](https://openairdocs.org/engine/allison-250-ser-250hp) (registry code 03002, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 610 - Year built: 1971 - Airframe hours: 11447.5 - Engines: Rolls-Royce C20B 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: North Carolina State Highway Patrol - Registered owner: North Carolina State Highway Patrol - Airworthiness certificate: None - Last inspection: 100 hour, August 18, 2020 - Departed: JNX, Smithfield, NC - Destination: Same as departure - Airport: 3NC2, Garner Road Heliport - Equipment: Satellite tracking device, ADS-B, Electronic flight bag or handheld device, Handheld GPS, Onboard weather ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 32; injuries: minor; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane, helicopter; medical: class 2, without waivers/limitations; last flight review May 27, 2020; seat: right; restraint: 4-point; flight hours: 1,878 total, 101 in this make and model, 1,587 as pilot in command, 104 in the last 90 days, 49 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 130° at 8 knots - Visibility: 10 statute miles - Temperature: 77 °F, dew point 61 °F - Altimeter: 30.33 inHg - Observed at: KRDU, 12 nm away - METAR: KRDU 081851Z 13008KT 10SM BKN040 BKN250 25/16 A3033 RMK AO2 SLP268 T02500161 ## 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 20201108014929A](https://openairdocs.org/incident/20201108014929A), Nov 8, 2020: Bell 206A, Raleigh, NC, Substantial damage. Pilot approaching to land at the heliport (3NC2) over the trees flying northeast with the winds variable between 090 and 120. When the pilot was about 300 feet… ## Docket (7 files) The files NTSB released with the investigation on June 24, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=102253. 13.8 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 5.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12291086&FileExtension=pdf&FileName=6120_1_Recd%2011%2018%202020_Redacted-Rel.pdf - Statement from pilot (item 2, PDF, 1 page, 165 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12294117&FileExtension=pdf&FileName=Statement%20from%20PIC_Redacted-Rel.pdf - Statement from passenger who just disembarked (item 3, PDF, 1 page, 107 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12374926&FileExtension=pdf&FileName=Passenger%20Statement_Redacted-Rel.pdf - Record of NTSB conversation (item 4, PDF, 3 pages, 138 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12380149&FileExtension=pdf&FileName=Record%20of%20NTSB%20Conversation_Redacted-Rel.pdf - 3NC2 approach and departure diagrams (item 5, PDF, 4 pages, 3.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12297534&FileExtension=pdf&FileName=3NC2%20Approaches-Departures-Rel.pdf - Investigative photographs (item 6, PDF, 4 pages, 4 photos, 4.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12381066&FileExtension=pdf&FileName=Investigative%20Photographs-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 7, PDF, 1 page, 729 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12295984&FileExtension=pdf&FileName=Fully%20Executed%20Wreckage%20Release%20Form_N123NC_ERA21LA040_Redacted-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.