# NTSB ERA24LA171: Robinson Helicopter R44 II, N331EL, South Kingstown, RI, April 9, 2024 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: April 9, 2024, 08:30 local (12:30 UTC) - Place: South Kingstown, RI - Coordinates: 41.437414, -71.572543 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.4374&lon=-71.5725&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 194061 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA24LA171 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/194061/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=194061 - Page: https://openairdocs.org/ntsb/ERA24LA171 ## Probable cause The pilot’s failure to maintain clearance from the water while maneuvering at low altitude. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Robinson Helicopter R44 II, 39 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=7640122), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Terrain: water](https://openairdocs.org/ntsb-findings/03021020): Environmental issues › Physical environment · Effect on personnel; cases with it: [Robinson Helicopter R44 II, 4 cases](https://openairdocs.org/ntsb-findings/03021020/cases.md?model=7640122), [All aircraft, 97 cases](https://openairdocs.org/ntsb-findings/03021020/cases.md) - [Perception/orientation/illusion: visual illusion/disorientation](https://openairdocs.org/ntsb-findings/02022015): Personnel issues › Psychological · Pilot; cases with it: [Robinson Helicopter R44 II, 3 cases](https://openairdocs.org/ntsb-findings/02022015/cases.md?model=7640122), [All aircraft, 51 cases](https://openairdocs.org/ntsb-findings/02022015/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: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) (defining event); cases with it: [Robinson Helicopter R44 II, 45 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=7640122), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md) ## Analysis The pilot was practicing various flight profiles over a pond in his helicopter. After completing the first profile, he began a profile that included a normal takeoff, a 10-ft hover, an acceleration to 40 kts, a climb to 50 ft above ground level, then a return to a 10-ft hover. On the pilot’s second attempt at this maneuver, when decelerating and descending back down to a 10 ft hover, the helicopter descended too low. The front skids caught the water and the helicopter descended into the pond, substantially damaging the tail rotor assembly and the main rotor blades. The pilot reported that there were no preimpact mechanical malfunctions or failures of the helicopter that would have precluded normal operation. He also described that the weather and water conditions at the time of the accident were “calm and clear with no wind ripples on the water surface,” and that this produced a “mirroring effect” that hindered his depth perception. ## Aircraft - Registration: [N331EL](https://openairdocs.org/aircraft/N331EL), registered now, S/N 14667, built 2023 (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: 14667 - Year built: 2023 - Airframe hours: 50 - Engines: Lycoming IO-540-AE1A5 245 hp reciprocating - Damage: Substantial damage - Flight: Other work use, Part 91 - Airworthiness certificate: Standard, Normal - Departed: OQU, North Kingstown, RI - Equipment: Video recording device, ADS-B, Auto-pilot, Electronic multifunction display, Electronic primary flight display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 54; injuries: none; commercial; airplane ratings: single-engine land; medical: class 2, with waivers/limitations; last flight review October 10, 2023; seat: right; restraint: 3-point; flight hours: 12,050 total, 7,550 in this make and model, 11,850 as pilot in command, 39 in the last 90 days, 19 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 340° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 61 °F, dew point 30 °F - Altimeter: 30.03 inHg - Observed at: WST, 12 nm away - METAR: KWST 091253Z AUTO 34004KT 10SM CLR 16/M01 A3003 RMK AO2 SLP167 T01611011 ## 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 20240409004319A](https://openairdocs.org/incident/20240409004319A), Apr 9, 2024: Robinson Helicopter Company R44 II, South Kingston, RI, Destroyed. The pilot reported he flew southwest at 800 feet MSL to wordens' pond to perform a flight over the pond. He began executing a series of flight parameters,… ## Docket (2 files) The files NTSB released with the investigation on May 29, 2024, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=194061. 6.9 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 2.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17038877&FileExtension=pdf&FileName=6120.1_Redacted-Rel.pdf - Investigative photos (item 2, PDF, 3 pages, 4.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17038887&FileExtension=pdf&FileName=Investigative%20Photos_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.