# NTSB ANC21LA079: Robinson Helicopter R44 II, N878CB, Pelican, AK, August 30, 2021 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: August 30, 2021, 13:15 local (21:15 UTC) - Place: Pelican, AK - Coordinates: 58.0903, -136.41332 - Nearby events: https://openairdocs.org/map.md?lat=58.0903&lon=-136.4133&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: External load event (Rotorcraft)](https://openairdocs.org/ntsb-events/480) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration - NTSB case key (mKey): 103782 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC21LA079 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/103782/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=103782 - Page: https://openairdocs.org/ntsb/ANC21LA079 ## Probable cause The pilot’s improper preflight planning to ensure adequate power to hover out-of-ground effect while conducting external load operations. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Planning/preparation: performance calculations](https://openairdocs.org/ntsb-findings/02061010): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Robinson Helicopter R44 II, 3 cases](https://openairdocs.org/ntsb-findings/02061010/cases.md?model=7640122), [All aircraft, 114 cases](https://openairdocs.org/ntsb-findings/02061010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: External load event (Rotorcraft)](https://openairdocs.org/ntsb-events/480) (defining event); cases with it: [Robinson Helicopter R44 II, 3 cases](https://openairdocs.org/ntsb-events/480/sequence.md?model=7640122), [All aircraft, 51 cases](https://openairdocs.org/ntsb-events/480/sequence.md) - [Landing-flare/touchdown: Hard landing](https://openairdocs.org/ntsb-events/092); cases with it: [Robinson Helicopter R44 II, 40 cases](https://openairdocs.org/ntsb-events/092/sequence.md?model=7640122), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) ## Analysis The pilot reported that he was conducting helicopter external sling load operations to a remote mountain top. At the drop off site, while in a hover about 20 ft above the ground, with his attention focused outside to ensure he cleared terrain and obstacles, he felt the helicopter begin to settle. The rpm began to decay, the low rotor rpm light illuminated, and the horn sounded. He immediately lowered the collective, released the cargo and impacted the ground coming to rest on top of the cargo. The helicopter sustained substantial damage to the rotor system and vertical stabilizer. The pilot reported that there were no preaccident mechanical malfunctions or anomalies with the helicopter that would have precluded normal operation, and that the accident may have been prevented if he had received additional training from the company to include flying at gross weight with and without external loads. In addition to having pilots check for available power in an out-of-ground effect hover with altitudes and escape routes before committing to the approach. ## Aircraft - Registration: [N878CB](https://openairdocs.org/aircraft/N878CB), registered now, S/N 10404, built 2004 (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: 10404 - Year built: 2004 - Airframe hours: 3570 - Engines: LYCOMING IO-540-AE1A% 260 horsepower reciprocating - Damage: Substantial damage - Flight: External load, Part 133 - Operator: Helicopter Air Alaska LLC - Registered owner: Helicopter Air Alaska LLC - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, August 1, 2021 - Destination: Same as departure - Flight plan: Company VFR - Equipment: ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 39; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: airplane, helicopter; medical: class 2, without waivers/limitations; last flight review June 3, 2021; seat: front; restraint: 3-point; flight hours: 1,635 total, 750 in this make and model, 1,500 as pilot in command, 100 in the last 90 days ## Weather - Conditions: Visual (VMC), Day - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 55 °F, dew point 50 °F - Altimeter: 30.03 inHg - Observed at: PAEL, 6 nm away - METAR: PAEL 302045Z VRB04KT 20SM SKC 13/10 A3003 RMK SEA 0 SWELL 2 SW NOSPECI ## 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 20210830008789A](https://openairdocs.org/incident/20210830008789A), Aug 30, 2021: Robinson Helicopter Company R44 II, Gustavus, AK, Substantial damage. Pilot was transporting propane '420' tanks by external short sling (10 ft reach + 3 foot harness) from beach refueling at sea level to remote repeater site at… ## Other investigations on N878CB (1) 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. - [NTSB ANC20CA068](https://openairdocs.org/ntsb/ANC20CA068), Jul 10, 2020: Robinson R44 (N878CB), Ketchikan, AK, substantial damage. Probable cause: The crew leader's decision to throw a chainsaw bar into the moving arc of the main rotor blade. ## Docket (2 files) The files NTSB released with the investigation on April 18, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=103782. 1.6 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12698205&FileExtension=pdf&FileName=6120_Redacted-Rel.pdf - Photos (item 2, PDF, 2 pages, 127 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12704121&FileExtension=pdf&FileName=Photo%20Array-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.