# NTSB investigations: Lycoming O-540-F1B5

NTSB aviation accident and incident investigations since 1962: the probable cause, findings, aircraft, crew, weather and docket of each, linked to the FAA registry and the FAA’s own reports.

Page 1 of 2 · 73 cases

## Latest cases

- [NTSB ERA27LA017](https://openairdocs.org/ntsb/ERA27LA017.md): Robinson Helicopter R44 · Kinnelon, NJ · Accident · Minor injuries · Class 4 · Limited · Investigation open · Oct 20, 2026 · N744CJ
- [NTSB ANC26LA082](https://openairdocs.org/ntsb/ANC26LA082.md): Robinson Helicopter R44 · Macedonia, IA · Accident · Minor injuries · Class 4 · Limited · Investigation open · Aug 9, 2026 · N197HL · Substantial damage
- [NTSB CEN26LA289](https://openairdocs.org/ntsb/CEN26LA289.md): Robinson Helicopter R44 Raven 1 · Scribner, NE · Accident · No injuries · Class 4 · Limited · Final report · Jul 18, 2026 · N26EH · Substantial damage
  > The pilot's failure to maintain clearance from power lines while maneuvering at low-level altitude during an agricultural operation.
- [NTSB CEN26LA259](https://openairdocs.org/ntsb/CEN26LA259.md): Robinson Helicopter R44 · Adair, IA · Accident · No injuries · Class 3 · Limited · Preliminary report · Jul 18, 2026 · N484AT · Substantial damage
  > On July 18, 2026, about 1440 central daylight time, a Robinson Helicopter Company R44, N484AT, was substantially damaged when it was involved in an accident near Adair, Iowa. The pilot was not injured. The helicopter was operated as a Title 14 Code of Federal…
- [NTSB ANC26LA051](https://openairdocs.org/ntsb/ANC26LA051.md): Robinson R44 · Pembroke Pines, FL · Accident · Minor injuries · Class 3 · Limited · Preliminary report · Jun 13, 2026 · N336SG · Substantial damage
  > On June 13, 2026, about 1318 eastern daylight time, a Robinson R44 Raven I helicopter, N336SG, was substantially damaged when it was involved in an accident at the North Perry Airport (HWO), Hollywood, Florida. The pilot and three passengers sustained minor…
- [NTSB ERA26LA048](https://openairdocs.org/ntsb/ERA26LA048.md): Robinson Helicopter R44 · Cookeville, TN · Accident · No injuries · Class 4 · Limited · Final report · Nov 14, 2025 · N668TM · Substantial damage
  > The pilot’s failure to maintain an appropriate decent rate during approach, resulting in a hard landing.
- [NTSB CEN24LA343](https://openairdocs.org/ntsb/CEN24LA343.md): Robinson Helicopter R44 · Grand Forks, ND · Accident · No injuries · Class 4 · Limited · Final report · Sep 6, 2024 · N896J · Substantial damage
  > The student pilot’s failure to maintain helicopter control which resulted in impact with the ground. Contributing to the outcome was the flight instructor’s delayed remedial action.
- [NTSB ANC24LA077](https://openairdocs.org/ntsb/ANC24LA077.md): Robinson R44 · Honolulu, HI · Accident · No injuries · Class 3 · Limited · Final report · Aug 19, 2024 · N740RH · Substantial damage
  > A failure of the flex plate yoke flange assembly due to incorrectly torqued bolts. Contributing was the maintenance personnel’s inadequate inspection of the tail rotor flex plate assembly.
- [NTSB CEN24LA303](https://openairdocs.org/ntsb/CEN24LA303.md): Robinson Helicopter R44 · Bryant, IA · Accident · No injuries · Class 3 · Limited · Final report · Aug 3, 2024 · N225ML · Substantial damage
  > A loss of engine power during takeoff for reasons that could not be determined, resulting in impact with terrain.
- [NTSB WPR24LA251](https://openairdocs.org/ntsb/WPR24LA251.md): Robinson Helicopter R44 · Carlsbad, CA · Accident · Minor injuries · Class 4 · Limited · Final report · Jul 18, 2024 · N886JB · Substantial damage
  > The pilot’s failure to maintain lateral control of the helicopter while departing with a crosswind, which resulted in a dynamic rollover.
- [NTSB ERA24LA166](https://openairdocs.org/ntsb/ERA24LA166.md): Robinson Helicopter R44 · Key Biscayne, FL · Accident · Serious injuries · Class 3 · Limited · Final report · Apr 6, 2024 · N234ZT · Substantial damage
  > A loss of engine power for reasons that could not be determined.
- [NTSB GAA24WA123](https://openairdocs.org/ntsb/GAA24WA123.md): Robinson Helicopter R44 · Suben, Austria · Accident · No injuries · Class 5 · Foreign · Mar 20, 2024 · N5050 · Substantial damage
- [NTSB CEN24LA135](https://openairdocs.org/ntsb/CEN24LA135.md): Robinson Helicopter R44 · Knox City, TX · Accident · No injuries · Class 4 · Limited · Final report · Mar 13, 2024 · N3040P · Substantial damage
  > The pilot’s failure to maintain directional control during takeoff, which resulted in a rollover and an impact with terrain.
- [NTSB ERA24LA079](https://openairdocs.org/ntsb/ERA24LA079.md): Robinson Helicopter R44 · Daytona Beach, FL · Accident · No injuries · Class 4 · Limited · Final report · Dec 30, 2023 · N828AK · 2 aircraft · Substantial damage
  > The UAS operator’s failure to operate within the limitations of the COA that he was using to operate inside class C airspace, which resulted in a collision between the UAS and the helicopter.
- [NTSB OPS24LA011](https://openairdocs.org/ntsb/OPS24LA011.md): Diamond Aircraft Ind DA20-C1 · North Las Vegas, NV · Incident · No injuries · Class 4 · Limited · Final report · Dec 9, 2023 · N857PA · 2 aircraft · No damage
  > The local controller’s loss of situational awareness, inadequate provision of traffic advisory or safety alert information, and lack of positive control, that resulted in a near-midair collision.
- [NTSB CEN24LA027](https://openairdocs.org/ntsb/CEN24LA027.md): Robinson Helicopter R44 · Rowlett, TX · Accident · Minor injuries · Class 3 · Limited · Final report · Oct 26, 2023 · N141CD · Substantial damage
  > A malfunction of the helicopter’s Engine Monitoring Unit (EMU)/Governor Controller for undetermined reasons. Contributing to the accident was the flight instructor’s failure to turn off the EMU/Governor Controller per the emergency checklist when the…
- [NTSB CEN24LA004](https://openairdocs.org/ntsb/CEN24LA004.md): Robinson Helicopter R44 · Hochatown, OK · Accident · No injuries · Class 3 · Limited · Final report · Oct 1, 2023 · N379SH · Substantial damage
  > A total loss of engine power during a practice autorotation due to the improper engine idle setting and rigging of the carburetor heat control which resulted in a hard landing.
- [NTSB ERA23LA350](https://openairdocs.org/ntsb/ERA23LA350.md): Robinson Helicopter R44 · Immokalee, FL · Accident · Serious injuries · Class 4 · Limited · Final report · Aug 26, 2023 · N4147Q · Substantial damage
  > The flight instructor’s inadequate supervision of the student pilot during hover flight, which resulted in main rotor blade contact with the ground after the student pilot applied a sudden control input.
- [NTSB CEN23LA328](https://openairdocs.org/ntsb/CEN23LA328.md): Robinson Helicopter R44 · Hanlontown, IA · Accident · No injuries · Class 4 · Limited · Final report · Jul 26, 2023 · N467HA · Substantial damage
  > The pilot’s failure to maintain clearance from a cable during spray operations.
- [NTSB CEN23LA219](https://openairdocs.org/ntsb/CEN23LA219.md): Robinson Helicopter R44 · Pontiac, MI · Accident · No injuries · Class 4 · Limited · Final report · May 31, 2023 · N7102Z · Substantial damage
  > The flight crew’s inadequate compensation for gusting wind, and the flight instructor’s delayed remedial action, which resulted in impact with the ground.
- [NTSB CEN23LA130](https://openairdocs.org/ntsb/CEN23LA130.md): Robinson Helicopter R44 · De Kalb, TX · Accident · Serious injuries · Class 3 · Limited · Final report · Mar 11, 2023 · N4164T · Substantial damage
  > The pilot’s inability to maintain control of the helicopter due to his failure to maintain rotor speed. Contributing to the accident was the failure of the helicopter’s low rotor speed warning system.
- [NTSB WPR23LA041](https://openairdocs.org/ntsb/WPR23LA041.md): Cessna 172M · Las Vegas, NV · Accident · No injuries · Class 3 · Limited · Final report · Nov 18, 2022 · N88E · 2 aircraft · Substantial damage
  > The student helicopter pilot’s failure to follow the tower controller’s landing instructions, which resulted in a midair collision.
- [NTSB ERA23LA021](https://openairdocs.org/ntsb/ERA23LA021.md): Robinson Helicopter R44 · Daytona Beach, FL · Accident · Minor injuries · Class 4 · Limited · Final report · Oct 14, 2022 · N306MB · Substantial damage
  > The pilot’s misjudged landing point which resulted in a loss of control and collision with terrain.
- [NTSB WPR22LA363](https://openairdocs.org/ntsb/WPR22LA363.md): Robinson Helicopter R44 · Cedar City, UT · Accident · No injuries · Class 3 · Limited · Final report · Sep 30, 2022 · N297SU · Substantial damage
  > A partial loss of engine power due to a damaged cylinder intake valve and subsequent collision with terrain during an autorotation.
- [NTSB ERA22LA357](https://openairdocs.org/ntsb/ERA22LA357.md): Robinson Helicopter R44 · Leghighton, PA · Accident · Serious injuries · Class 4 · Limited · Final report · Aug 3, 2022 · N45CA · Substantial damage
  > The pilot’s improper recovery from a bounced landing on a slope, which resulted in dynamic rollover.
- [NTSB ERA22LA256](https://openairdocs.org/ntsb/ERA22LA256.md): Robinson Helicopter R44 · North Myrtle Beach, SC · Accident · No injuries · Class 3 · Limited · Final report · May 26, 2022 · N132TC · Substantial damage
  > The fractured attachment lug on the forward clutch shaft yoke due to fatigue failure with multiple origins.
- [NTSB CEN22FA151](https://openairdocs.org/ntsb/CEN22FA151.md): Robinson Helicopter R44 · Rowlett, TX · Accident · 2 fatal · Class 3 · Field · Final report · Mar 25, 2022 · N514CD · Destroyed
  > A loss of helicopter control while maneuvering, which resulted in main rotor blade contact with the tailboom in flight, tail boom separation, and an uncontrolled descent.
- [NTSB ERA22LA131](https://openairdocs.org/ntsb/ERA22LA131.md): Robinson Helicopter R44 · Miami Beach, FL · Accident · Serious injuries · Class 3 · Limited · Final report · Feb 19, 2022 · N544SB · Substantial damage
  > A loss of engine power due to a stuck valve, which resulted in an autorotation and a hard landing in water.
- [NTSB CEN21LA350](https://openairdocs.org/ntsb/CEN21LA350.md): Robinson Helicopter R44 · Waukon, IA · Accident · Minor injuries · Class 4 · Limited · Final report · Aug 4, 2021 · N775AK · Substantial damage
  > The pilot’s failure to maintain adequate clearance from a powerline during an agricultural application pass.
- [NTSB CEN21LA452](https://openairdocs.org/ntsb/CEN21LA452.md): Robinson Helicopter R44 · Mineral Point, WI · Accident · No injuries · Class 4 · Limited · Final report · Jul 20, 2021 · N44XB · Substantial damage
  > The pilot’s failure to see and avoid a wire during an aerial application flight, resulting in a collision with the wire.
- [NTSB ERA21FA200](https://openairdocs.org/ntsb/ERA21FA200.md): Robinson Helicopter R44 · Wingate, NC · Accident · 1 fatal · Class 3 · Field · Final report · May 2, 2021 · N4528T · Substantial damage
  > The pilot’s failure to maintain clearance from a power line during a low-level aerial application flight, resulting in tail rotor impact with the power line, a loss of control, and subsequent impact with the ground.
- [NTSB ERA21LA191](https://openairdocs.org/ntsb/ERA21LA191.md): Robinson Helicopter R44 · Forkston, PA · Accident · 1 fatal · Class 3 · Limited · Final report · Apr 23, 2021 · N4055N · Destroyed
  > The pilot’s inadequate preflight weather planning, which resulted in an inadvertent encounter with instrument meteorological conditions at night, spatial disorientation, and collision with terrain.
- [NTSB CEN21LA095](https://openairdocs.org/ntsb/CEN21LA095.md): Robinson Helicopter R44 · Morris, IL · Accident · Minor injuries · Class 4 · Limited · Final report · Dec 20, 2020 · N3264U · Substantial damage
  > The pilot's inadequate pedal application during liftoff with a tailwind, which resulted in a loss of yaw control and a subsequent impact with terrain.
- [NTSB CEN21LA084](https://openairdocs.org/ntsb/CEN21LA084.md): Robinson R44 · Colorado City, TX · Accident · 2 fatal · Class 3 · Limited · Final report · Dec 10, 2020 · N7085Z · Destroyed
  > The pilot’s loss of control and exceedance of performance and/or structural limitations during low-altitude operations, which resulted in an inflight breakup.. Contributing to the accident was the pilot’s impairment from the effects of tetrahydrocannabinol.
- [NTSB CEN20CA313](https://openairdocs.org/ntsb/CEN20CA313.md): Robinson R44 · Dakota, IL · Accident · No injuries · Class 4 · Data collection · Final report · Jul 27, 2020 · N570WH · Substantial damage
  > The pilot’s failure to maintain main rotor clearance from a ground obstacle during a landing.
- [NTSB ERA20CA260](https://openairdocs.org/ntsb/ERA20CA260.md): Robinson R44 · Whitehall, MD · Accident · No injuries · Class 4 · Data collection · Final report · Jul 24, 2020 · N350DM · Substantial damage
  > The pilot's failure to maintain adequate clearance from a known obstacle while landing from a hover.
- [NTSB CEN20CA300](https://openairdocs.org/ntsb/CEN20CA300.md): Robinson R44 · Dickeyville, WI · Accident · No injuries · Class 4 · Data collection · Final report · Jul 20, 2020 · N570WH · Substantial damage
  > The pilot did not maintain clearance from wires during an aerial application flight.
- [NTSB CEN20LA286](https://openairdocs.org/ntsb/CEN20LA286.md): Robinson R44 · Welsh, LA · Accident · Minor injuries · Class 3 · Limited · Final report · Jul 2, 2020 · N7511D · Substantial damage
  > A partial loss of engine power while in flight due to corrosion of engine components, which resulted in a loss of control and a subsequent impact with terrain.
- [NTSB GAA19CA509](https://openairdocs.org/ntsb/GAA19CA509.md): Robinson R44 · Cypress Island, WA · Accident · Serious injuries · Data collection · Final report · Aug 21, 2019 · N7186P · Substantial damage
  > The pilot's failure to maintain adequate clearance from a tree while maneuvering at a low altitude.
- [NTSB CEN19LA230](https://openairdocs.org/ntsb/CEN19LA230.md): Robinson R44 · Ida Grove, IA · Accident · Minor injuries · Class 3 · Limited · Final report · Jul 21, 2019 · N459TA · Substantial damage
  > A total loss of engine power during an aerial application flight for undetermined reasons.
- [NTSB CEN19LA174](https://openairdocs.org/ntsb/CEN19LA174.md): Robinson R44 · Key West, FL · Accident · No injuries · Class 3 · Limited · Final report · Jun 17, 2019 · N1241W · Substantial damage
  > The failure of maintenance personnel to properly secure the right-side tail boom mounting bolts which resulted in the failure of the bolts and an inflight separation of the tail rotor.
- [NTSB WPR19FA123](https://openairdocs.org/ntsb/WPR19FA123.md): Robinson R44 · Kailua, HI · Accident · 3 fatal · Class 3 · Field · Final report · Apr 29, 2019 · N808NV · Destroyed
  > The helicopter’s encounter with a strong downdraft or outflow boundary while operating at a higher than recommended airspeed in turbulence which resulted in a low-G condition, excessive main rotor flapping, and an in-flight breakup when the main rotor…
- [NTSB GAA19CA124](https://openairdocs.org/ntsb/GAA19CA124.md): Robinson R44 · Santa Maria Island, FL · Accident · Serious injuries · Data collection · Final report · Jan 2, 2019 · N772MG · Substantial damage
  > The pilot's loss of helicopter control while maneuvering at a low altitude after being struck in the head by a bird.
- [NTSB GAA19CA063](https://openairdocs.org/ntsb/GAA19CA063.md): Robinson R44 · Knox City, TX · Accident · No injuries · Data collection · Final report · Nov 18, 2018 · N4167Y · Substantial damage
  > The pilot's failure to maintain adequate airspeed with a tailwind, which resulted in the helicopter settling with power, and his subsequent incorrect collective application while attempting to recover, which resulted in a loss of helicopter control due to a…
- [NTSB WPR19LA013](https://openairdocs.org/ntsb/WPR19LA013.md): Robinson R44 · Kaneohe, HI · Accident · Serious injuries · Class 3 · Limited · Final report · Oct 23, 2018 · N4132H · Substantial damage
  > The pilot’s sudden incapacitation from an undiagnosed heart condition during flight, which resulted in a hard landing.
- [NTSB WPR18LA269](https://openairdocs.org/ntsb/WPR18LA269.md): Robinson R44 · Wahiawa, HI · Accident · No injuries · Class 3 · Limited · Final report · Sep 18, 2018 · N632NV · Substantial damage
  > Loss of oil in flight as a result of a loose oil filter adapter which resulted in the pilot initiating an immediate landing to an open field. Contributing to the accident was the pilot's manipulation of the throttle that led to a reduction in rotor rpm, which…
- [NTSB GAA18CA450](https://openairdocs.org/ntsb/GAA18CA450.md): Robinson R44 · Lantana, FL · Accident · Minor injuries · Data collection · Final report · Jul 27, 2018 · N479AT · Substantial damage
  > The student pilot’s improper pitch control during landing, which resulted in a dynamic rollover.
- [NTSB GAA18CA408](https://openairdocs.org/ntsb/GAA18CA408.md): Robinson R44 · Rulo, NE · Accident · No injuries · Data collection · Final report · Jul 10, 2018 · N144DJ · Substantial damage
  > The pilot's improper collective application, which resulted in low rotor rpm during the takeoff climb and a subsequent ground collision. Contributing to the accident was the pilot’s self-induced pressure to complete the operation.
- [NTSB CEN18FA215](https://openairdocs.org/ntsb/CEN18FA215.md): Robinson Helicopter R44 · Oshkosh, WI · Accident · 1 fatal · Field investigation · Final report · Jun 9, 2018 · N529DW · Substantial damage
  > The pilot's decision to fly over the river at a low altitude and his failure to maintain clearance with wires during low-level flight.
- [NTSB GAA18CA247](https://openairdocs.org/ntsb/GAA18CA247.md): Robinson Helicopter R44 · Sonora, TX · Accident · No injuries · Data collection · Final report · Apr 18, 2018 · N4487D · Substantial damage
  > The pilot’s failure to maintain clearance from trees while maneuvering at a low altitude.

Next page: https://openairdocs.org/ntsb.md?engine=42353&page=2

## The whole list in SQL

Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS:

```sql
SELECT c."ntsbNumber", c."eventDate", c."eventType", c."eventCity", c."eventStateOrRegion", a.n_number, a."aircraftMake", a."aircraftModel", c."highestInjuryLevel", c."totalFatal", c."completionStatus", c.report_url
FROM 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c LEFT JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = c."mKey" AND a.position = 1
WHERE c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('42353'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=42353

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