# NTSB WPR13CA204: Bell 206B, N4237M, Wells, NV, April 20, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: April 20, 2013, 10:40 local (17:40 UTC) - Place: Wells, NV - Coordinates: 41.365833, -114.998336 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.3658&lon=-114.9983&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report August 13, 2013 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 86698 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR13CA204 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/86698/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=86698 - Page: https://openairdocs.org/ntsb/WPR13CA204 ## Probable cause The pilot's failure to maintain clearance from an obstacle while maneuvering at a low altitude. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: use of equip/system](https://openairdocs.org/ntsb-findings/02063015): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Bell 206B, 5 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md?model=1181511), [All aircraft, 1,391 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md) - [Object/animal/substance](https://openairdocs.org/ntsb-findings/03022000): Environmental issues › Physical environment · Not specified; cases with it: [Bell 206B, 2 cases](https://openairdocs.org/ntsb-findings/03022000/cases.md?model=1181511), [All aircraft, 224 cases](https://openairdocs.org/ntsb-findings/03022000/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Bell 206B, 20 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=1181511), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/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) (defining event); cases with it: [Bell 206B, 34 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=1181511), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md) - [Maneuvering-low-alt flying: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Bell 206B, 57 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1181511), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Maneuvering-low-alt flying: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Bell 206B, 21 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=1181511), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis The pilot reported that he was flying the helicopter to specific locations within hilly sage and brush covered terrain in order for his passenger to set mining claim stakes at various intervals. Movement between the stake locations was typically conducted at a low altitude. The pilot stated that as he flew the helicopter over the crest of a hill, he felt the helicopter shudder and vibrate, and he initiated an autorotation to an open field. After what he described as an uneventful landing, the pilot noticed that the tailrotor and its drive shaft were damaged. The pilot further reported that he noticed a bush with several broken branches that was located along the helicopter's flight path, and he believed that the tailrotor struck that bush while he was maneuvering. The pilot reported no preimpact mechanical malfunctions or failures with the helicopter that would have precluded normal operation. ## Factual narrative The pilot reported that he was flying the helicopter to specific locations within hilly sage and brush covered terrain in order for his passenger to set mining claim stakes at various intervals of 300, 600, and 1,500 feet. Movement between locations was typically conducted at a low altitude. The pilot stated that as he flew the helicopter over the crest of a hill, he felt a shudder and subsequent vibration and initiated an autorotation to an open field. Following an uneventful landing, the pilot noticed that the tailrotor and tailrotor drive shaft were damaged. The pilot further reported that during recovery of the helicopter, he located a bush with several broken branches which was located within the flight path of the helicopter and felt that the tailrotor struck the bush while he was maneuvering. The pilot reported no preimpact mechanical malfunctions or failures with the helicopter would have precluded normal operation. ## Aircraft - Registration: [N4237M](https://openairdocs.org/aircraft/N4237M), registered now, S/N 4055, built 1989 (OpenAirDocs) - Reported make and model: BELL 206B - Registry model: [Bell 206B](https://openairdocs.org/model/bell-206b) (registry code 1181511) (OpenAirDocs) - Registry engine: [Rolls-Royce 250-C20B](https://openairdocs.org/engine/rolls-royce-250-c20b) (registry code 54385, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 4055 - Airframe hours: 7751 - Engines: ROLLS-ROYC 250-C20B 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Air drop, Part 91 - Operator: Reeder Flying Service - Registered owner: Reeder Flying Service - Airworthiness certificate: Standard, Normal - Last inspection: Annual, March 20, 2013, 67 hours before - Departed: Wells, NV - Destination: Wells, NV - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 56; injuries: none; flight instructor, commercial; airplane ratings: single-engine land; instrument ratings: helicopter; medical: class 2, with waivers/limitations; last flight review May 25, 2013; seat: right; flight hours: 7,115 total, 2,709 in this make and model, 6,978 as pilot in command, 68 in the last 90 days, 35 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 290° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: 4,400 ft broken - Temperature: 48 °F, dew point 30 °F - Altimeter: 30.20 inHg - Observed at: EKO, 23 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 20130420005949A](https://openairdocs.org/incident/20130420005949A), Apr 20, 2013: Bell 206B3, Wells, NV, Substantial damage. On 4/20/2013 at 10:40 a.m., helicopter N4237M, a Bell 206B3, struck a 8-10 foot bush with the tail rotor. This resulted in significant vibrations. The pilot… ## Docket (1 files) The files NTSB released with the investigation on June 12, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=86698. 1.9 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40393294&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.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.