# NTSB investigations: Prop/rotor parameters

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 4 · 182 cases

## Latest cases

- [NTSB CEN26LA168](https://openairdocs.org/ntsb/CEN26LA168.md): Robinson Helicopter R44 · Mount Blanco, TX · Accident · Minor injuries · Class 4 · Limited · Final report · Apr 17, 2026 · N445JS · Substantial damage
  > The pilot’s failure to maintain proper main rotor rpm during a low-level turn, which resulted in the main rotor rpm drooping, a loss of control at an altitude too low for recovery, and a subsequent impact with terrain.
- [NTSB ERA26LA119](https://openairdocs.org/ntsb/ERA26LA119.md): Tabor W Coates AR-1 · Kissimmee, FL · Accident · No injuries · Class 4 · Limited · Final report · Feb 17, 2026 · N220SM · Substantial damage
  > The pilot’s failure to obtain the proper rotor rpm during the takeoff roll which resulted in a loss of control.
- [NTSB CEN25LA380](https://openairdocs.org/ntsb/CEN25LA380.md): Bell 407 · Decatur, TX · Accident · Minor injuries · Class 4 · Limited · Final report · Sep 16, 2025 · N407WA · Substantial damage
  > The instructor candidate’s erroneous operation of the throttle during an autorotation from altitude with power recovery, which resulted in a hard landing.
- [NTSB ERA25LA237](https://openairdocs.org/ntsb/ERA25LA237.md): Gyro Technic GT-VX2 · Swanzey, NH · Accident · Minor injuries · Class 3 · Limited · Final report · Jun 23, 2025 · N62XF · Substantial damage
  > The pilot’s failure to maintain rotor rpm of the gyroplane during a low approach, while distracted by other aircraft in the airport traffic pattern, which resulted in the pilot’s decision to perform an off-runway landing.
- [NTSB WPR24LA262](https://openairdocs.org/ntsb/WPR24LA262.md): Hiller UH-12E · Bonners Ferry, ID · Accident · No injuries · Class 4 · Limited · Final report · Jul 24, 2024 · N3375T · Substantial damage
  > The pilot’s improper selection of a landing site, which resulted in a main rotor strike. Contributing to the accident was the pilot’s improper performance planning and altitude selection over water, which resulted in an rpm droop.
- [NTSB CEN24FA248](https://openairdocs.org/ntsb/CEN24FA248.md): Rotorway Scorpion 133 · Andale, KS · Accident · 1 fatal · Class 3 · Field · Final report · Jul 5, 2024 · N51017 · Destroyed
  > The pilot’s abrupt control inputs, which resulted in a low-G condition, main rotor mast bumping, and subsequent severing of the tailboom by the main rotor blades.
- [NTSB WPR24FA200](https://openairdocs.org/ntsb/WPR24FA200.md): Robinson Helicopter R44 II · Bluestem, WA · Accident · 2 fatal · Class 3 · Field · Final report · Jun 19, 2024 · N323TT · Destroyed
  > The pilot’s failure to manage main rotor rpm during an autorotation, which resulted in a loss of helicopter control. Contributing to the accident was a loss of power for reasons that could not be determined.
- [NTSB ANC24LA039](https://openairdocs.org/ntsb/ANC24LA039.md): Robinson Helicopter R22 Beta · Kailua-Kona, HI · Accident · No injuries · Class 4 · Limited · Final report · May 30, 2024 · N333PJ · Substantial damage
  > The flight instructor’s failure to implement the correct action for low rotor RPM recovery.
- [NTSB CEN24LA013](https://openairdocs.org/ntsb/CEN24LA013.md): Magni M24 · Mount Sterling, IL · Accident · No injuries · Class 3 · Limited · Final report · Oct 16, 2023 · N90HM · Substantial damage
  > The pilot’s failure to maintain gyroplane control on the downwind leg, which resulted in impact with terrain. Contributing to the accident was the pilot’s distraction.
- [NTSB CEN23LA389](https://openairdocs.org/ntsb/CEN23LA389.md): Mcdonnell Douglas Heli 530FF · Liberty Hill, TX · Accident · No injuries · Class 4 · Limited · Final report · Aug 31, 2023 · N530JR · Substantial damage
  > The pilot’s improper recovery from a practice autorotation resulting in a hard landing. Contributing to the accident was the instructor’s inadequate supervision of the pilot receiving instruction.
- [NTSB ERA23LA287](https://openairdocs.org/ntsb/ERA23LA287.md): Robinson Helicopter R44 · Myrtle Beach, SC · Accident · Minor injuries · Class 4 · Limited · Final report · Jul 4, 2023 · N7507X · Substantial damage
  > The pilot’s failure to maintain control of the helicopter during a hover taxi, which resulted in a rollover.
- [NTSB CEN23LA199](https://openairdocs.org/ntsb/CEN23LA199.md): Bell Helicopter Textron Canada 407 · Abbeville, LA · Accident · No injuries · Class 4 · Limited · Final report · May 23, 2023 · N451PH · Substantial damage
  > The pilot’s failure to maintain proper helicopter control during autorotation that resulted in an abnormal ground contact which caused the subsequent main rotor strike on the tail boom that severed the tail rotor driveshaft. Contributing to the accident was…
- [NTSB ERA23LA146](https://openairdocs.org/ntsb/ERA23LA146.md): Hughes 269A · Titusville, FL · Accident · No injuries · Class 4 · Limited · Final report · Mar 9, 2023 · N8911F · Substantial damage
  > The pilot’s failure to maintain adequate main rotor RPM during an autorotation which resulted in a hard landing and subsequent rotor blade strike of the tail boom.
- [NTSB ANC23LA024](https://openairdocs.org/ntsb/ANC23LA024.md): Enstrom F-28C · Anchorage, AK · Accident · No injuries · Class 3 · Limited · Final report · Mar 5, 2023 · N5688R · Substantial damage
  > The pilot’s failure to maintain main rotor rpm on takeoff, which resulted in a forced run-on landing.
- [NTSB CEN22LA402](https://openairdocs.org/ntsb/CEN22LA402.md): MD Helicopters 369E · Pearland, TX · Accident · No injuries · Class 3 · Limited · Final report · Aug 30, 2022 · N1576F · Substantial damage
  > The pilot receiving instruction’s failure to maintain aircraft control, and the flight instructor’s delayed remedial action, which resulted in a hard landing.
- [NTSB ERA22LA269](https://openairdocs.org/ntsb/ERA22LA269.md): Walter S Johnson III AR-1 · Butler, PA · Accident · No injuries · Class 4 · Limited · Final report · Jun 11, 2022 · N688G · Substantial damage
  > The pilot’s failure to monitor rotor disk speed on takeoff, which resulted in blade flapping and the main rotor blades striking the gyroplane’s tail assembly.
- [NTSB CEN22LA078](https://openairdocs.org/ntsb/CEN22LA078.md): Bell Helicopter Textron Canada 407 · Bridgeport, TX · Accident · Minor injuries · Class 4 · Limited · Final report · Dec 14, 2021 · N862YB · Substantial damage
  > The pilot’s failure to maintain adequate main rotor RPM during an autorotation which resulted in a hard landing. Contributing to the accident was the pilot’s improper placement of the throttle during the initial practice power-on recovery autorotation.
- [NTSB WPR22FA053](https://openairdocs.org/ntsb/WPR22FA053.md): Russell W Dyer Vortex · Lakeport, CA · Accident · 1 fatal · Class 3 · Field · Final report · Dec 2, 2021 · N425RD · Substantial damage
  > The pilot’s loss of control for reasons that could not be determined and the delayed remedial action to recover from the power pushover event.
- [NTSB CEN21LA187](https://openairdocs.org/ntsb/CEN21LA187.md): Eurocopter EC120 · LeRoy, KS · Accident · No injuries · Class 3 · Limited · Final report · Apr 9, 2021 · N421PB · Substantial damage
  > The contamination of the fuel injection manifold filter due to improper maintenance, resulting in a partial loss of engine power during cruise flight. Contributing to the accident was the pilot’s delayed autorotation, which resulted in insufficient main rotor…
- [NTSB CEN21LA155](https://openairdocs.org/ntsb/CEN21LA155.md): Robinson Helicopter R44 · Dunn, TX · Accident · No injuries · Class 3 · Limited · Final report · Feb 26, 2021 · N7184N · Substantial damage
  > The loss of rotor RPM for reasons that could not be determined based on available evidence.
- [NTSB WPR21LA093](https://openairdocs.org/ntsb/WPR21LA093.md): Mcdonnell Douglas Helicopter 369E · Queen Creek, AZ · Accident · No injuries · Class 4 · Limited · Final report · Jan 22, 2021 · N90TG · Substantial damage
  > The pilot's uncoordinated flight control inputs while entering a hover, which lead to a loss of aircraft control which resulted in the left skid making contact with the ground, causing the helicopter to roll on its side.
- [NTSB CEN20CA395](https://openairdocs.org/ntsb/CEN20CA395.md): Bell 407 · Fort Worth, TX · Accident · No injuries · Class 4 · Data collection · Final report · Sep 15, 2020 · N489DM · Substantial damage
  > The flight instructor’s delay in rolling the throttle to the fly position during a practice autorotation maneuver that resulted in a hard landing.
- [NTSB CEN20LA273](https://openairdocs.org/ntsb/CEN20LA273.md): Aerospatiale AS355 · Rifle, CO · Accident · Serious injuries · Class 3 · Limited · Final report · Jul 11, 2020 · N708AC · Destroyed
  > A loss of tail rotor effectiveness, the pilot’s subsequent loss of helicopter control, and collision with terrain.
- [NTSB CEN20LA261](https://openairdocs.org/ntsb/CEN20LA261.md): Enstrom 280 · Des Moines, IA · Accident · Minor injuries · Class 3 · Limited · Final report · Jul 4, 2020 · N282SH · Destroyed
  > The partial loss of rotor and engine speed during approach for landing, which resulted in an autorotation and impact with terrain. The reason for the partial loss of rotor and engine speed could not be determined based on the available evidence. Contributing…
- [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 GAA20CA044](https://openairdocs.org/ntsb/GAA20CA044.md): Richard B Carpenter AR-1 · Brooksville, FL · Accident · No injuries · Data collection · Final report · Oct 21, 2019 · N147AR · Substantial damage
  > The pilot's failure to attain the proper rotor speed before takeoff, which resulted in the rotor blade striking the rudder. Contributing to the accident was the pilot's failure to abort the takeoff in a timely manner.
- [NTSB WPR19LA205](https://openairdocs.org/ntsb/WPR19LA205.md): Md Helicopter 369 · Eugene, OR · Accident · Serious injuries · Class 3 · Limited · Final report · Jul 28, 2019 · N438RC · Substantial damage
  > The left seat pilot’s failure to account for environmental conditions conducive to a loss of tail rotor effectiveness, which resulted in a loss of tail rotor effectiveness and subsequent loss of control.
- [NTSB GAA19CA463](https://openairdocs.org/ntsb/GAA19CA463.md): Hughes 269A · Springfield, TN · Accident · No injuries · Data collection · Final report · Jul 24, 2019 · N269RR · Substantial damage
  > The pilot’s failure to maintain helicopter control and a loss of tail rotor effectiveness while hover-taxiing and turning toward a taxiway in gusting crosswind conditions, which resulted in a dynamic rollover.
- [NTSB WPR19LA194](https://openairdocs.org/ntsb/WPR19LA194.md): Bell 47G 3B 1 · Mosby, MT · Accident · Serious injuries · Class 3 · Limited · Final report · Jul 13, 2019 · N3078G · Substantial damage
  > The pilot’s failure to account for environmental conditions conducive to a loss of tail rotor effectiveness, which resulted in a loss of tail rotor effectiveness and subsequent loss of control. Contributing to the accident was the pilot’s inappropriate…
- [NTSB ERA19TA213](https://openairdocs.org/ntsb/ERA19TA213.md): Continental Copters Tomcat MK6C · Franklin, KY · Accident · Minor injuries · Class 3 · Final report · Jul 8, 2019 · N41830 · Substantial damage
  > The pilot’s failure to maintain main rotor rpm after takeoff, which resulted in a collision with terrain.
- [NTSB CEN19LA187](https://openairdocs.org/ntsb/CEN19LA187.md): Robinson R22 · Danbury, TX · Accident · No injuries · Class 3 · Limited · Final report · Jun 28, 2019 · N26498 · Substantial damage
  > A failed electrical relay, which provided an improper indication of a governor and clutch problem, which resulted in the pilot conducting a precautionary landing during which he failed to maintain sufficient main rotor speed.
- [NTSB ERA19LA171](https://openairdocs.org/ntsb/ERA19LA171.md): Bell 206 · New York, NY · Accident · No injuries · Class 3 · Limited · Final report · May 15, 2019 · N26BB · Substantial damage
  > The pilot's failure to compensate for adverse wind on final approach, which resulted in a loss of tail rotor effectiveness and aircraft control.
- [NTSB GAA19CA226](https://openairdocs.org/ntsb/GAA19CA226.md): Guimbal Cabri · McMinnville, OR · Accident · No injuries · Data collection · Final report · Apr 26, 2019 · N367PA · Substantial damage
  > The pilot's improper landing flare during a turning, full-down autorotation, which resulted in a lower-than-normal rotor rpm, a faster-than-normal ground run speed, and the subsequent loss of directional control, a runway excursion, and a roll-over.…
- [NTSB CEN19LA067](https://openairdocs.org/ntsb/CEN19LA067.md): Bell 47G · Belen, NM · Accident · No injuries · Limited investigation · Final report · Jan 11, 2019 · N3755Z · Substantial damage
  > The pilot's failure to maintain adequate main rotor speed while the helicopter was in an out-of-ground effect hover.
- [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 CEN19FA009](https://openairdocs.org/ntsb/CEN19FA009.md): Robinson R22 · Fulton, MO · Accident · 1 fatal · Class 2 · Field · Final report · Oct 17, 2018 · N923SH · Destroyed
  > A total loss of engine power due to carburetor icing, the pilot's delayed application of carburetor heat, and the pilot's delay in entering an autorotation following the loss of engine power, which resulted in a main rotor stall due to low rotor rpm and an…
- [NTSB CEN18LA314](https://openairdocs.org/ntsb/CEN18LA314.md): Airbus EC 130 T2 · Mullen, NE · Accident · Serious injuries · Limited investigation · Final report · Aug 3, 2018 · N130TG · Substantial damage
  > The pilot’s inadequate and incorrect antitorque pedal application during a tight, decelerating turn downwind, which resulted in a loss of yaw control.
- [NTSB GAA18CA424](https://openairdocs.org/ntsb/GAA18CA424.md): Bell 206 · New Castle, IN · Accident · No injuries · Data collection · Final report · Jul 16, 2018 · N39LR · Substantial damage
  > The pilot's failure to ensure that the fill hose was disconnected from the helicopter before takeoff, which resulted in the fill hose striking the tail rotor and the subsequent loss of tail rotor effectiveness. Contributing to the accident was inadequate…
- [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 GAA18CA250](https://openairdocs.org/ntsb/GAA18CA250.md): Michael R Alexander Mosquito XE · Iron Station, NC · Accident · Minor injuries · Data collection · Final report · May 2, 2018 · N725JC · Destroyed
  > The noncertificated pilot’s decision to practice hovering the helicopter in a confined space, which resulted in the tail rotor striking a tree.
- [NTSB ERA18LA135](https://openairdocs.org/ntsb/ERA18LA135.md): Heard Alan E Mosquito XE · Albion, NY · Accident · Serious injuries · Class 3 · Limited · Final report · Apr 24, 2018 · N911CY · Destroyed
  > The pilot's inadvertent, improper configuration of the engine fuel system, which resulted in an excessively lean air-to-fuel ratio and resulted in a loss of engine power; and the pilot's subsequent failure to maintain main rotor rpm following the loss of…
- [NTSB GAA18CA159](https://openairdocs.org/ntsb/GAA18CA159.md): Hughes 269 · Jacksonville, FL · Accident · No injuries · Data collection · Final report · Mar 10, 2018 · N9020M · Substantial damage
  > The pilot’s failure to maintain rotor rpm during a practice autorotation, which resulted in ground contact and a dynamic rollover.
- [NTSB ERA18LA095](https://openairdocs.org/ntsb/ERA18LA095.md): Robert Snyder Autogyro Calidus · Beaufort, SC · Accident · 1 fatal · Limited investigation · Final report · Mar 5, 2018 · N221YT · Substantial damage
  > The gyroplane pilot's failure to maintain rotor speed and aircraft control as he was attempting to return to the runway during a low-altitude simulated engine-out maneuver.
- [NTSB GAA18LA131](https://openairdocs.org/ntsb/GAA18LA131.md): Robinson Helicopter R22 · Charleston, SC · Accident · No injuries · Limited investigation · Final report · Feb 14, 2018 · N337H · Substantial damage
  > The flight instructor’s abrupt evasive maneuver to avoid a reported unmanned aerial system, which resulted in a loss of forward airspeed and settling with power and a subsequent collision with trees and terrain.
- [NTSB WPR18MA087](https://openairdocs.org/ntsb/WPR18MA087.md): Eurocopter EC130 · Peach Springs, AZ · Accident · 5 fatal · Class 3 · Major · Final report · Feb 11, 2018 · N155GC · Destroyed
  > A loss of tail rotor effectiveness, the pilot’s subsequent loss of helicopter control, and collision with terrain during an approach to land in gusting, tailwind conditions in an area of potential downdrafts and turbulence.
- [NTSB GAA18CA114](https://openairdocs.org/ntsb/GAA18CA114.md): Wayne Miller Sport Copter II · Van Nuys, CA · Accident · No injuries · Data collection · Final report · Jan 29, 2018 · N767LW · Substantial damage
  > The pilot’s decision to takeoff in gusting wind conditions with insufficient rotor rpm.
- [NTSB WPR18LA041](https://openairdocs.org/ntsb/WPR18LA041.md): Robinson Helicopter R22 · Truckee, CA · Accident · Serious injuries · Class 3 · Limited · Final report · Nov 30, 2017 · N47WH · Substantial damage
  > The flight instructor’s failure to execute a power recovery from a non-stabilized autorotative descent, which resulted in a hard landing.
- [NTSB WPR17LA211](https://openairdocs.org/ntsb/WPR17LA211.md): Robinson Helicopter R22 · Long Beach, CA · Accident · Serious injuries · Limited investigation · Final report · Sep 20, 2017 · N7514S · Substantial damage
  > The student pilot's failure to maintain rotor rpm during the crosswind landing approach and his subsequent improper decision to initiate an autorotation instead of applying corrective control inputs after the helicopter experienced normal airframe vibration.…
- [NTSB ERA17MA316](https://openairdocs.org/ntsb/ERA17MA316.md): Eurocopter Deutschland MBB BK 117 · Hertford, NC · Accident · 4 fatal · Class 2 · Major · Final report · Sep 8, 2017 · N146DU · Destroyed
  > A failure of the rear bearing in the No. 2 engine, which (1) created multiple and likely unexpected and confusing cockpit indications, resulting in the pilot's improper diagnosis and subsequent erroneous shutdown of the No. 1 engine, and (2) the resulting…
- [NTSB GAA17CA495](https://openairdocs.org/ntsb/GAA17CA495.md): Bell 206 · Minden, NV · Accident · No injuries · Data collection · Final report · Aug 20, 2017 · N6259C · Substantial damage
  > The pilot’s failure to maintain helicopter control during landing due to a loss of tail rotor effectiveness.

Next page: https://openairdocs.org/ntsb-findings/01062052/cases.md?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 f.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_findings.parquet' f WHERE starts_with(f."findingCode", '01062052'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb-findings/01062052/cases

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