# NTSB CEN10LA477: Bell 206B, N54BE, Rocky Mount, MO, August 13, 2010 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 13, 2010, 11:20 local (16:20 UTC) - Place: Rocky Mount, MO - Coordinates: 38.269443, -92.75222 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.2694&lon=-92.7522&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Dynamic rollover](https://openairdocs.org/ntsb-events/231) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report April 7, 2011 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA-Kansas City FSDO - NTSB case key (mKey): 76954 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN10LA477 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/76954/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=76954 - Page: https://openairdocs.org/ntsb/CEN10LA477 ## Probable cause A dynamic rollover inadvertently induced by the pilot during landing. ## 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: [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. - [Landing: Dynamic rollover](https://openairdocs.org/ntsb-events/231) (defining event); cases with it: [All aircraft, 161 cases](https://openairdocs.org/ntsb-events/231/sequence.md) - [Landing: Roll over](https://openairdocs.org/ntsb-events/097); cases with it: [All aircraft, 261 cases](https://openairdocs.org/ntsb-events/097/sequence.md) ## Analysis The pilot reported that the approach and landing were normal. After landing, he lowered the collective and began to decrease engine power by manipulating the throttle closed. Before the throttle was completely closed, the helicopter suddenly rolled to the right and came to rest on its right side, incurring damage to the airframe, main rotor, and tail boom. A postaccident examination did not reveal any anomalies consistent with a preimpact failure or malfunction. Dynamic rollover is the tendency of a helicopter to continue rolling when the critical angle is exceeded, if one skid is on the ground, and the helicopter is pivoting around that point. Dynamic rollover is possible when a skid is caught by a projection on the surface or when landing on a slope. ## Factual narrative On August 13, 2010, about 1120 central daylight time, a Bell 206B helicopter, N54BE, piloted by an airline transport pilot, was substantially damaged during landing at the pilot's private helipad in Rocky Mount, Missouri. The personal flight was being conducted under 14 Code of Federal Regulations Part 91 without a flight plan. Visual meteorological conditions prevailed. The pilot, who was the sole occupant, was not injured. The helicopter departed Jefferson City Memorial Airport (JEF), Jefferson City, Missouri, about 1050. The pilot reported that the approach and landing were normal. He stated that after landing, he lowered the collective and began to "roll off" the throttle. However, before the throttle was completely off, the helicopter "suddenly rolled to the right." The aircraft came to rest on its right side with damage to the airframe, main rotor, and tail boom. A post accident examination did not reveal any anomalies consistent with a pre-impact failure or malfunction. Flight control continuity was confirmed. The pilot reported weather conditions as clear skies, with light and variable winds at the time of the accident. Weather conditions recorded at the Lee C. Fine Memorial Airport (AIZ), located about 14 miles southeast of the accident site, at 1115, included clear skies and winds from the southwest at 8 knots. The Federal Aviation Administration (FAA) Rotorcraft Flying Handbook noted that helicopters are susceptible to a lateral rolling tendency referred to as dynamic rollover. The handbook stated that, "Dynamic rollover is possible even during takeoff and landings on relative level ground, if one wheel or skid is on the ground and thrust (lift) is approximately equal to the weight of the helicopter. If the takeoff or landing is not performed properly, a roll rate could develop around the wheel or skid that is on the ground." ## Aircraft - Registration: N54BE (not matched to a registry record) - Reported make and model: BELL 206B - Category: Helicopter - Serial number: 2875 - Airframe hours: 10355 - Engines: ALLISON 250-C20 SER 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Computer Service Professionals Inc - Registered owner: Computer Service Professionals Inc - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 8, 2010 - Departed: JEF, Jefferson City, MO - Destination: PVT, Rocky Mount, MO ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 55; injuries: none; airline transport; airplane ratings: single-engine land, single-engine sea, multi-engine land; instrument ratings: airplane; medical: class 2, without waivers/limitations; last flight review July 13, 2010; seat: right; flight hours: 10,365 total, 73 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 210° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 93 °F, dew point 75 °F - Altimeter: 29.80 inHg - Observed at: AIZ, 14 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 20100813042489A](https://openairdocs.org/incident/20100813042489A), Aug 13, 2010: Bell 206B, Rocky Mount, MO, Substantial damage. The pilot stated that after the aircraft touched down, he lowered the collective and, while rolling off the power, the aircraft suddenly rolled to the right.… ## Docket (3 files) The files NTSB released with the investigation on November 4, 2010, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=76954. 632 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 492 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40336200&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Conversation Record -- FAA (item 2, .PDF, 45 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40338541&FileExtension=.PDF&FileName=Conversation%20Record%20--%20FAA-Master.PDF - FAA Rotorcraft Flying Handbook -- Excerpt (item 3, .PDF, 95 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40338542&FileExtension=.PDF&FileName=FAA%20Rotorcraft%20Flying%20Handbook%20--%20Excerpt-Master.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.