# NTSB ANC25LA099: Robinson Helicopter R44 II, N74435, Petersville, AK, August 29, 2025 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: August 29, 2025, 11:50 local (19:50 UTC) - Place: Petersville, AK · Remote Lodge - Coordinates: 62.54243, -151.444 - Nearby events: https://openairdocs.org/map.md?lat=62.5424&lon=-151.4440&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Settling with power/vortex ring state](https://openairdocs.org/ntsb-events/244) - Highest injury: No injuries - Injuries: 4 uninjured - Status: Completed, report May 21, 2026 - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Alaska Regional Office - Parties: FAA - NTSB case key (mKey): 200960 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC25LA099 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/200960/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=200960 - Page: https://openairdocs.org/ntsb/ANC25LA099 ## Probable cause The pilot’s exceedance of the helicopter’s available power while landing in a remote confined area, which resulted in rotor droop and a hard landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: descent rate](https://openairdocs.org/ntsb-findings/01062037): Aircraft › Aircraft oper/perf/capability · Capability exceeded (probable cause); cases with it: [Robinson Helicopter R44 II, 7 cases](https://openairdocs.org/ntsb-findings/01062037/cases.md?model=7640122), [All aircraft, 242 cases](https://openairdocs.org/ntsb-findings/01062037/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Robinson Helicopter R44 II, 99 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7640122), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Attention/monitoring: task monitoring/vigilance](https://openairdocs.org/ntsb-findings/02021520): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Robinson Helicopter R44 II, 5 cases](https://openairdocs.org/ntsb-findings/02021520/cases.md?model=7640122), [All aircraft, 330 cases](https://openairdocs.org/ntsb-findings/02021520/cases.md) - [Attention/monitoring: attention](https://openairdocs.org/ntsb-findings/02021510): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Robinson Helicopter R44 II, 7 cases](https://openairdocs.org/ntsb-findings/02021510/cases.md?model=7640122), [All aircraft, 226 cases](https://openairdocs.org/ntsb-findings/02021510/cases.md) - [Wind: tailwind](https://openairdocs.org/ntsb-findings/03034015): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Robinson Helicopter R44 II, 13 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md?model=7640122), [All aircraft, 594 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: Settling with power/vortex ring state](https://openairdocs.org/ntsb-events/244) (defining event); cases with it: [Robinson Helicopter R44 II, 6 cases](https://openairdocs.org/ntsb-events/244/sequence.md?model=7640122), [All aircraft, 52 cases](https://openairdocs.org/ntsb-events/244/sequence.md) ## Analysis The pilot reported that he was transporting three passengers and their equipment to a remote landing zone (LZ) in mountainous terrain. According to the operator, the helicopter’s estimated gross weight was 2,440 lbs., approximately 60 lbs. below the maximum gross weight of 2,500 lbs. The pilot stated that a guide onboard the helicopter was directing him to the LZ. He had initially planned to conduct a northwesterly reconnaissance flyover of the landing area; however, he became distracted when the guide pointed out the intended LZ directly ahead. As a result, the pilot immediately turned toward the site and initiated a steep approach without completing the planned flyover. During the approach, the pilot reported an increasing descent rate. He applied additional collective to arrest the descent, after which the full-throttle annunciator illuminated. Despite the collective being fully raised, the helicopter continued descending and subsequently impacted the ground. The helicopter landed hard and rolled over, sustaining substantial damage to the fuselage and the main and tail rotor drive systems. Following the accident, the pilot estimated the wind was from the south at approximately 15 to 20 knots. He reported no preimpact mechanical failures or malfunctions that would have precluded normal operation. ## Aircraft - Registration: [N74435](https://openairdocs.org/aircraft/N74435), registered now, S/N 10718, 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 series](https://openairdocs.org/engine/lycoming-io-540-series) (registry code 41530, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 10718 - Year built: 2005 - Airframe hours: 7372 - Engines: Lycoming IO-540-AE1A5 245 horsepower reciprocating - Damage: Substantial damage - Flight: Part 135 - Operator: Pollux Aviation Ltd - Registered owner: Pollux Aviation Ltd - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, August 5, 2025, 18 hours before - Departed: 4AK6, Wasilla, AK - Destination: Same as departure - Flight plan: Company VFR - Equipment: ADS-B, Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 55; injuries: none; commercial; instrument ratings: helicopter; medical: class 2, with waivers/limitations; last flight review June 14, 2025; seat: right; restraint: 5-point; flight hours: 2,628 total, 1,187 in this make and model, 2,510 as pilot in command, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 11 knots - Visibility: 10 statute miles - Lowest ceiling: 1,400 ft broken - Temperature: 52 °F, dew point 48 °F - Altimeter: 29.89 inHg - Turbulence: Light - Observed at: PATK, 40 nm away - METAR: PATK 291953Z 18011KT 10SM -RA BKN014 OVC024 11/09 A2989 RMK AO2 SLP126 P0001 T01060094 $ ## 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 20250829017419A](https://openairdocs.org/incident/20250829017419A), Aug 29, 2025: Robinson Helicopter Company R44 II, Petersville, AK, Substantial damage. Pilot was shuttling a group of 10 tour passengers from one ridge to another, both takeoff/landing areas approximately 3800 ft MSL. The first group to be… ## Docket (2 files) The files NTSB released with the investigation on May 22, 2026, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=200960. 2.3 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 12 pages, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19263405&FileExtension=pdf&FileName=ANC25LA099%206120_Redacted-Rel.pdf - Investigative photograph (item 2, PDF, 2 pages, 652 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=20349744&FileExtension=pdf&FileName=ANC25LA099%20Photo-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.