# NTSB CEN12LA258: Bell 206B, N2068X, Amarillo, TX, April 26, 2012 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: April 26, 2012, 16:45 local (21:45 UTC) - Place: Amarillo, TX - Coordinates: 35.218055, -101.703613 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.2181&lon=-101.7036&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report October 29, 2013 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Rolls-Royce Corporation, Transportation Safety Board of Canada, Bell Helicopter, FAA Lubbock FSDO - NTSB case key (mKey): 83488 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN12LA258 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/83488/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=83488 - Page: https://openairdocs.org/ntsb/CEN12LA258 ## Probable cause The pilot's failure to maintain helicopter control during landing in gusty wind conditions associated with a thunderstorm, which resulted in a loss of tail rotor effectiveness. ## 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 206B, 45 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=1181511), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Wind](https://openairdocs.org/ntsb-findings/03034000): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Bell 206B, 2 cases](https://openairdocs.org/ntsb-findings/03034000/cases.md?model=1181511), [All aircraft, 110 cases](https://openairdocs.org/ntsb-findings/03034000/cases.md) - [Performance/control parameters: yaw control](https://openairdocs.org/ntsb-findings/01062024): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Bell 206B, 7 cases](https://openairdocs.org/ntsb-findings/01062024/cases.md?model=1181511), [All aircraft, 149 cases](https://openairdocs.org/ntsb-findings/01062024/cases.md) - [Convective weather: thunderstorm](https://openairdocs.org/ntsb-findings/03033010): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Bell 206B, 1 case](https://openairdocs.org/ntsb-findings/03033010/cases.md?model=1181511), [All aircraft, 100 cases](https://openairdocs.org/ntsb-findings/03033010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: Windshear or thunderstorm](https://openairdocs.org/ntsb-events/390); cases with it: [Bell 206B, 1 case](https://openairdocs.org/ntsb-events/390/sequence.md?model=1181511), [All aircraft, 224 cases](https://openairdocs.org/ntsb-events/390/sequence.md) - [Landing: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Bell 206B, 32 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=1181511), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Uncontrolled descent: 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) ## Analysis The pilot reported that he was aware of lightning and a thunderstorm that was close to the airport and approaching from the southwest. He was flying an approach to the southeast and planned to approach “straight in” to the hangar. As he began to flare to stop the descent, movement of the cyclic stick was briefly hindered by a laptop computer in the left seat passenger’s lap; the passenger immediately moved the obstructing laptop computer. The helicopter was then about level with the hangar roof when, according to the pilot, a strong gust of wind forced the helicopter’s nose up, and the helicopter briefly entered into a climbing right turn. The helicopter then began a sudden uncommanded turn, spinning to the right. The pilot reported that left pedal input had no effect and that he had only partial control as the helicopter made a full 360-degree turn, descended, and impacted the ground. During the impact with the ground, the lower fuselage sustained crushing damage, and the main rotor separated from the main rotor mast. A significant amount of fuel spilled during the impact, but no postimpact fire occurred. After the crash, both occupants were able to extract themselves from the wreckage unassisted. According to a weather observation station at the airport, the wind was from 120 degrees at 19 knots, gusting to 25 knots, and a thunderstorm was recorded on the field. Federal Aviation Administration Advisory Circular 90-95, “Unanticipated Right Yaw in Helicopters,” describes loss of tail rotor effectiveness (LTE) as a critical, low speed aerodynamic flight characteristic that could result in an uncommanded rapid yaw rate that does not subside of its own accord and, if not corrected, could result in the loss of aircraft control. The pilot was operating the helicopter in a low airspeed, out-of-ground-effect, high-power-demand flight condition, which could have resulted in LTE. ## Factual narrative On April 26, 2012, about 1645 central daylight time, a Bell 206B helicopter, N2068X, impacted terrain while landing at Rick Husband Amarillo International Airport (AMA), Amarillo, Texas. The pilot and passenger suffered minor injuries and the helicopter was substantially damaged. The helicopter was registered to and operated by Chesapeake Bay Helicopters Inc., under the provisions of 14 Code of Federal Regulations Part 91, as an aerial surveillance flight. Day visual meteorological conditions prevailed and a visual flight rules flight plan was not filed. The helicopter was destined for AMA and had departed about 1600 from Moore County Airport (DUX), Dumas, Texas. The pilot was aware of lightning and a thunderstorm that was close and approaching the airport from the southwest. He was flying an approach to the southeast and was landing “straight in to the hangar”. As he began to flare to stop the descent his cyclic stick was briefly hindered by interference from a laptop computer in the left seat passenger’s lap and the passenger immediately moved the obstructing laptop computer. The helicopter was then about level with the hangar roof and the pilot reported that a strong gust of wind forced the helicopter’s nose up and it briefly entered into a climbing right turn. The helicopter then began a sudden uncommanded turn spinning to the right. The pilot reported that left pedal input had no effect and he had only partial control as the helicopter made a full 360 degree turn, descended, and impacted the ground. During the impact with the ground the lower fuselage sustained crushing damage and the main rotor separated from the main rotor mast. There was a significant fuel spill during the impact, but no postimpact fire. After the crash both occupants were able to extract themselves from the wreckage unassisted. An examination of the helicopter revealed no preimpact mechanical anomalies or malfunctions that would have precluded normal operations. At 1653 an automated weather observation facility at AMA reported: wind from 120 degrees at 19 knots gusting to 25 knots, visibility 10 miles or greater, thunderstorm, few clouds at 9,000 feet above ground level (agl), scattered clouds at 11,000 feet agl, temperature 28 degrees Celsius, dew point temp 14 degrees Celsius, altimeter 29.84 inches of Mercury, peak wind during previous hour from 110 degrees at 27 knots at 1634, thunderstorm began at 1647. Federal Aviation Administration Advisory Circular (AC) 90-95, “Unanticipated Right Yaw in Helicopters,” issued in February 1995, described loss of tail rotor effectiveness (LTE) as a critical, low speed aerodynamic flight characteristic that could result in an uncommanded rapid yaw rate that does not subside of its own accord and, if not corrected, could result in the loss of aircraft control. The AC also stated, “LTE is not related to a maintenance malfunction and may occur in varying degrees in all single main rotor helicopters at airspeeds less than 30 knots…Anymaneuver which requires the pilot to operate in a high-power, low-airspeed environment with a left crosswind or tailwind creates an environment where unanticipated right yaw may occur.” When operating at airspeeds below effective translational lift, pilots should avoid OGE hover and high power demand situations... ## Aircraft - Registration: [N2068X](https://openairdocs.org/deregistered/N2068X-2017-09-07), registration cancelled 2017-09-07, S/N 3393, built 1981 (OpenAirDocs) - Reported make and model: BELL 206B - Registry model: [Bell 206B](https://openairdocs.org/model/bell-206b) (registry code 1181511) (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: 3393 - Airframe hours: 12498 - Engines: Allison 250-C20B 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Aerial observation, Part 91 - Operator: Chesapeake Bay Helicopters Inc - Registered owner: Chesapeake Bay Helicopters Inc - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 25, 2012, 5 hours before - Departed: DUX, Dumas, TX - Destination: AMA, Amarillo, TX - Airport: AMA, Rick Husband Amarillo Intl ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 32; injuries: minor; commercial; instrument ratings: helicopter; medical: class 2, with waivers/limitations; last flight review April 16, 2012; seat: right; flight hours: 1,105 total, 312 in this make and model, 1,061 as pilot in command, 107 in the last 90 days, 33 in the last 30 days, 6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 120° at 19 knots, gusting 25 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 57 °F - Altimeter: 29.84 inHg - Observed at: KAMA ## 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 20120426005909A](https://openairdocs.org/incident/20120426005909A), Apr 26, 2012: Bell 206B, Amarillo, TX, Substantial damage. On April 26, 2012, at approximately 1700 CDT, a Bell 206B jet ranger approached Rick Husband Amarillo international airport from the north. As the helicopter… ## Docket (6 files) The files NTSB released with the investigation on August 9, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=83488. 4.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40387882&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Crewmember Statements, Maps and Diagrams (item 2, .PDF, 1.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40387884&FileExtension=.PDF&FileName=Crewmember%20Statements,%20Maps%20and%20Diagrams-Master.PDF - Photo - Wreckage with the viewer looking to the southwest (Emergency Responder Photo) (item 3, .PDF, 233 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395225&FileExtension=.PDF&FileName=Photo%20-%20Wreckage%20with%20the%20viewer%20looking%20to%20the%20southwest%20%20(Emergency%20Responder%20Photo)-Master.PDF - Rolls-Royce Factual Report (item 4, .PDF, 11 photos, 849 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40387886&FileExtension=.PDF&FileName=Rolls-Royce%20Factual%20Report-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 5, .PDF, 179 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40387887&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Redacted.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 6, .PDF, 175 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40387888&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-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.