# NTSB CEN25LA105: Robinson Helicopter R44 II, N6555C, Edgemont, SD, February 27, 2025 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: February 27, 2025, 07:45 local (14:45 UTC) - Place: Edgemont, SD - Coordinates: 43.3512, -103.74767 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.3512&lon=-103.7477&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Cabin safety event](https://openairdocs.org/ntsb-events/110) - Highest injury: Serious injuries - Injuries: 1 serious, 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Central Region - Parties: FAA - NTSB case key (mKey): 199776 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN25LA105 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/199776/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=199776 - Page: https://openairdocs.org/ntsb/CEN25LA105 ## Probable cause The pilot’s failure to properly identify the proper anchor point for the supplemental harness and the crew’s incorrect use of the restraint system structure as an anchor point, which resulted in the separation of the structure. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Aircraft](https://openairdocs.org/ntsb-findings/01030000): Aircraft › Aircraft structures · Incorrect use/operation (probable cause); cases with it: [Robinson Helicopter R44 II, 1 case](https://openairdocs.org/ntsb-findings/01030000/cases.md?model=7640122), [All aircraft, 72 cases](https://openairdocs.org/ntsb-findings/01030000/cases.md) - [Info processing/decision: identification/recognition](https://openairdocs.org/ntsb-findings/02041510): Personnel issues › Action/decision · Flight crew (probable cause); cases with it: [Robinson Helicopter R44 II, 10 cases](https://openairdocs.org/ntsb-findings/02041510/cases.md?model=7640122), [All aircraft, 559 cases](https://openairdocs.org/ntsb-findings/02041510/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: Cabin safety event](https://openairdocs.org/ntsb-events/110) (defining event); cases with it: [Robinson Helicopter R44 II, 1 case](https://openairdocs.org/ntsb-events/110/sequence.md?model=7640122), [All aircraft, 151 cases](https://openairdocs.org/ntsb-events/110/sequence.md) ## Analysis The purpose of the flight was to survey and capture elk and was operated with the pilot and a non-flight crewmember, the gunner. The gunner’s purpose was to tranquilize elk from the maneuvering helicopter as the pilot positioned the helicopter to match the speed of a target elk. The gunner, who was clipped into the helicopter with a safety harness, fell out of the helicopter while conducting the elk capture operation and sustained serious injuries. The pilot landed the helicopter without further incident. A postaccident examination of the helicopter revealed that the anchor point for the front passenger seat restraint system separated and was still attached to the gunner’s harness. Examination of the separation surfaces revealed deformation along the circumference of each end of the tubing. The gunner was not using the helicopter’s passenger seat restraint system when he fell out of the helicopter; rather, he was using a harness restraint system that was anchored to the vertical tube of the helicopter’s supplemental shoulder harness guide system. The pilot stated that the gunner selected and secured the anchor point for the harness before the flight and the gunner stated that the pilot selected and secured the anchor point. According to the helicopter manufacturer, the anchor point utilized for the harness was not designed to sustain side loads, which resulted in its separation and the gunner falling out of the helicopter. ## Factual narrative On February 27, 2025, about 0745 central standard time, a Robinson Helicopter Company, R44 II, N6555C, was involved in an accident near Edgemont, South Dakota. The pilot was not injured and the non-flight crewmember was seriously injured. The helicopter was not damaged. The helicopter was operated as a Title 14 Code of Federal Regulations Part 91 aerial observation flight. The purpose of the flight was to survey and capture elk and was operated with the pilot and a non-flight crewmember, the gunner. The gunner’s purpose was to tranquilize elk from the maneuvering helicopter as the pilot positioned the helicopter to match the speed of a target elk. The pilot reported that the helicopter was maneuvering about 30 ft above ground level during an elk capture and surveying flight. The non-flight crewmember, who was seated in the right-rear passenger seat, fell out of the helicopter and was seriously injured. The pilot immediately landed the helicopter without further incident. According to the helicopter manufacturer, the C421-2 tube (vertical) and the C423-4 upper seatback support tube (horizontal) were part of the optional 5-point seat belt installation available for the front seats (Figure 1). The purpose of the C423-4 upper seatback support tube was to properly position and support the four shoulder harnesses for the front seat occupants. The purpose of the C421-2 tube was to transfer any downward loads applied to the upper seatback support tube to the C423-1 lower seatback support tube in the event of a hard landing. The manufacturer stated that it was not designed to sustain any side loads and does not require periodic maintenance or inspection other than overall condition. Post-flight examination of the helicopter revealed that the anchor point (vertical tube, C421-2) used to secure the supplemental restraint system to the helicopter separated from the surrounding structure (Figure 2). The hollow vertical tube remained intact but exhibited deformation on the outer circumference of one of its ends. The other end exhibited less deformation to the tube, its plastic cap, and hardware. Figure 1. Airframe restraint system Figure 2. Separated vertical tube The gunner reported that he secured the helicopter’s shoulder restraints by tucking them behind the seat, and the lap belt was buckled and laid flat against the seat to secure it during the flight. He reported that the supplemental restraint system’s anchor point is secured to the helicopter by the pilot before each flight in a designated position and that he “clips in” his end of the harness to the anchor point end of the harness before the flight. The gunner stated that the pilot had selected the harness anchor point. It was the same anchor point used on previous flights. The pilot reported that he briefed the gunner that the helicopter’s restraint system, which consisted of seat belts and shoulder harnesses, is the primary restraint and that any supplemental harness is secondary. He stated thathe allows the gunner to place the anchor point for the supplemental restraint system at his or her discretion because it is not required by regulation. ## Aircraft - Registration: [N6555C](https://openairdocs.org/aircraft/N6555C), registered now, S/N 10965, built 2005 (OpenAirDocs) - Reported make and model: ROBINSON HELICOPTER COMPANY R44 II - Registry model: [Robinson Helicopter R44 II](https://openairdocs.org/model/robinson-helicopter-r44-ii) (registry code 7640122) (OpenAirDocs) - Registry engine: [Lycoming IO-540-AE1A5](https://openairdocs.org/engine/lycoming-io-540-ae1a5) (registry code 41899, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 10965 - Year built: 2005 - Airframe hours: 4192.5 - Engines: Lycoming IO-540-AEA5 245 horsepower reciprocating - Damage: No damage - Flight: Aerial observation, Part 91 - Operator: Kiwi Air LLC - Registered owner: Kiwi Air LLC - Airworthiness certificate: Standard, Normal - Last inspection: Annual, January 25, 2025, 41 hours before - Departed: Rapid City, SD - Destination: Rapid City, SD - Airport: NONE, South Dakota Game, Fish, and Parks - Equipment: ADS-B, Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 40; injuries: none; flight instructor, flight engineer, commercial; medical: class 2, with waivers/limitations; last flight review September 30, 2024; seat: right; restraint: 5-point; flight hours: 10,041 total, 4,041 in this make and model, 9,791 as pilot in command, 56 in the last 90 days, 41 in the last 30 days, 7 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 30 °F, dew point 18 °F - Altimeter: 30.20 inHg - Icing: Unknown - Turbulence: Unknown - Observed at: KCUT, 24 nm away - METAR: METAR KCUT 271253Z AUTO 25005KT 10SM CLR M01/M08 A3020 RMK AO2 SLP250 T10111083 $= ## 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 20250227001329A](https://openairdocs.org/incident/20250227001329A), Feb 27, 2025: Robinson Helicopter Company R44 II, Edgemont, SD, No damage. On 2/27/25 at approximately 7:30AM mt, a Robinson R-44 [privacy data omitted], LLC was conducting an elk survey/capture operation when the gunner fell from the… ## Docket (6 files) The files NTSB released with the investigation on September 3, 2025, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=199776. 2.9 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 10 pages, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18678367&FileExtension=pdf&FileName=NTSB%20Form%206120_Redacted-Rel.pdf - Gunner statement (item 2, PDF, 1 page, 66 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18671759&FileExtension=pdf&FileName=Gunner%20MOR-Rel.pdf - Pilot statement (item 3, PDF, 1 page, 66 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18676467&FileExtension=pdf&FileName=MOR%20Pilot-Rel.pdf - Mor Robinson helicopter company (item 4, PDF, 2 pages, 529 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18688524&FileExtension=pdf&FileName=MOR%20Robinson%20Helicopter%20Company-Rel.pdf - Investigation photographs (item 5, PDF, 3 pages, 396 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18954267&FileExtension=pdf&FileName=Investigation%20Photographs%20CEN25LA105-Rel.pdf - Evidence control form (item 6, PDF, 1 page, 125 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18674820&FileExtension=pdf&FileName=Evidence%20Transfer%20Form%20signed_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.