NTSB investigations
44 cases where NTSB found Main rotor drive.
Cases per year
| 2008 | 6 |
|---|---|
| 2009 | 2 |
| 2010 | 2 |
| 2011 | 4 |
| 2012 | 2 |
| 2013 | 1 |
| 2014 | 2 |
| 2015 | 4 |
| 2016 | 3 |
| 2017 | 2 |
| 2018 | 4 |
| 2019 | 4 |
| 2020 | 2 |
| 2021 | 2 |
| 2022 | 1 |
| 2023 | 2 |
| 2024 | 1 |
Where
Open the mapLatest cases
Query with SQL
duckdb -csv -c "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\", '010463')) ORDER BY c.\"eventDate\" DESC, c.\"ntsbNumber\" DESC"
Prints the whole list as CSV. It reads the release’s Parquet files over HTTPS, so there’s nothing to download first. Install DuckDB to run it.
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", '010463')) ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
Run it at the DuckDB prompt, or in any tool that reads Parquet over HTTPS. More ways to query the release are on Use the data.
NTSB ANC24LA017Accident · Serious injuriesClass 3 · LimitedFinal reportMD Helicopter 369E/500E · Kekaha, HIMaintenance personnel’s noncompliance with maintenance manual procedures that required the removal of the overrunning clutch output bearing during the regreasing procedure, which resulted in inadequate regreasing of the bearing and the subsequent failure of…NTSB WPR24LA067Accident · No injuriesClass 3 · LimitedFinal reportBell 206B · El Centro, CAAn in-flight failure of the engine-to-transmission driveshaft due to a fatigue fracture of the forward-most flex plate in the forward KAflex coupling that resulted from a loose bolt attachment between the flex plate and the forward driveshaft coupling.…NTSB ERA23LA293Accident · Minor injuriesClass 3 · LimitedFinal reportHughes 369D · Waldorf, MDFatigue failure of the overrunning clutch outer race and a subsequent inflight loss of power due to abnormal bending loads as a result of improper reassembly of the clutch subassembly following maintenance and the presence of microcracks on the clutch’s outer…NTSB ERA22LA256Accident · No injuriesClass 3 · LimitedFinal reportRobinson Helicopter R44 · North Myrtle Beach, SCThe fractured attachment lug on the forward clutch shaft yoke due to fatigue failure with multiple origins.NTSB WPR21LA320Accident · Serious injuriesClass 3 · LimitedFinal reportRobinson Helicopter R22 Beta · West Jordan, UTThe pilot receiving instruction’s improper application of forward cyclic in a low rotor rpm condition and the instructor’s delayed remediation, which resulted in an impact with terrain.NTSB ANC21LA038Accident · No injuriesClass 3 · LimitedFinal reportEnstrom F-28F · Palmer, AKA loss of drive to the rotor system due to the disengagement of the main belt drive tensioning system, which resulted in a forced landing. The disengagement was due to inadequate clearance between the clutch handle and the roll pin in the handle bellcrank…NTSB CEN20LA330Accident · Serious injuriesClass 3 · LimitedFinal reportRobinson R44 · Logan, IAThe failure of the lower actuator bearing support brackets, which resulted in the misalignment of the clutch actuator, a loss of belt tension on the main rotor drive system, and a subsequent forced landing.NTSB WPR20LA228Accident · No injuriesClass 3 · LimitedFinal reportMd Helicopter 600 · San Andreas, CAThe failure of the output shaft of the overrunning clutch inner race due to frictional overheating of the shaft, which resulted from the failure of the output bearing’s stainless-steel grease seal.NTSB ERA20LA054Accident · Minor injuriesClass 3 · LimitedFinal reportRobinson R44 · San Antonio, TXMaintenance personnel’s failure to complete all necessary steps of a service bulletin and subsequent failure to identify the loose lower actuator bearing support bracket during inspections, which resulted in the misalignment of the clutch actuator, resulted…NTSB CEN19LA240Accident · Minor injuriesClass 3 · LimitedFinal reportRobinson R44 · Blair, NEThe failure of the lower actuator bearing support bracket, which resulted in the misalignment of the clutch actuator, the loss of belt tension on the main rotor drive system, and the subsequent forced landing on sloped terrain.NTSB CEN19LA106Accident · No injuriesClass 3 · LimitedFinal reportRobinson R22 · Madill, OKThe failure of the V-belts due to improper maintenance, which resulted in the loss of power to the helicopter's rotor system and subsequent forced landing on rough terrain.NTSB ERA19FA118Accident · 1 fatalClass 3 · FieldFinal reportHughes 369 · Talking Rock, GAA fatigue failure of the overrunning clutch subassembly due to abnormal bending loads due to cracks on the center engine mount, which resulted in an inflight loss of power. Contributing to the accident was the helicopter's low altitude and airspeed when the…NTSB CEN18LA334Accident · No injuriesClass 3 · LimitedFinal reportSchweizer 269C · Kindred, NDThe pilot’s failure to adequately inspect the lower coupling driveshaft during his preflight inspection and his non-compliance with an applicable airworthiness directive, which resulted in the failure of the forward drive splines of the lower coupling…NTSB WPR18LA133Accident · Minor injuriesClass 3 · LimitedFinal reportRobinson Helicopter R44 II · Borrego Springs, CAThe loss of the helicopter’s drive system for reasons that could not be determined from the available evidence, which led to an autorotation that resulted in a hard landing and rollover on uneven sandy terrain.NTSB WPR18FA088Accident · 4 fatalField investigationFinal reportHastings Thomas G Cirrus VK 30 · Agua Dulce, CAThe driveshaft fracture due to overstress loading and rotational bending as a result of the under-torqued nuts on the elastomeric couplings backing off and the subsequent in-flight separation of the horizontal fairing due to contact with the separated end of…NTSB ANC18LA020Accident · No injuriesLimited investigationFinal reportEurocopter France SA330J Puma · Pacific Ocean, JapanThe worn rear bearing of the freewheel unit. Contributing to the accident was the delay in analyzing an oil sample, which would have detected the increase in metal contaminants from the worn bearing.NTSB CEN17LA365Accident · No injuriesLimited investigationFinal reportGaddis Michael Exec 162 F · Plymouth, INA failure of the drive belt for reasons that could not be determined based on the available information.NTSB WPR17LA113Accident · Serious injuriesLimited investigationFinal reportBell 206B · Rockville, IDThe in-flight failure of the engine-to-transmission drive shaft due to a fatigue fracture of one of the KAflex flex frames caused by a loose bolt, which resulted in a total loss of engine power and a subsequent hard landing.NTSB WPR16FA072Accident · 1 fatalField investigationFinal reportBell 206B · Honolulu, HIThe in-flight failure of the engine-to-transmission drive shaft due to improper maintenance, which resulted in low main rotor rpm and a subsequent hard landing to water.NTSB CEN16LA105Accident · No injuriesLimited investigationFinal reportEnstrom TH-180 · Menominee, MIThe failure of the torque meter mounting bolts, which resulted in a loss of engine power to the main drive belt and rotors.NTSB CEN16LA096Accident · 1 fatalLimited investigationFinal reportRaymond Z Brown Condor · Centralia, ILThe failure of the prerotator belt, which impeded the engine's timing belt and resulted in a loss of engine power at low altitude.NTSB CEN15LA396Accident · No injuriesLimited investigationFinal reportBurns Mini 500 · Butler, MOThe pilot's failure to attain a proper landing flare following an autorotation for reasons that could not be determined based on available information.NTSB GAA15CA127Accident · No injuriesData collectionFinal reportPaquin Michael A A · Concord, NHThe pilot's inability to maintain directional control during takeoff, which resulted in a roll over. Contributing to the loss of control was the pilot's failure to disengage the main rotor brake prior to takeoff.NTSB CEN15CA155Accident · No injuriesData collectionFinal reportGaddis Michael Exec 162 F · Plymouth, INThe failure of the helicopter's main drive belt resulting in the pilot performing a forced landing, during which the helicopter's fuselage was substantially damage.NTSB WPR15LA109Accident · No injuriesLimited investigationFinal reportBell/Garlick UH 1H · Shelton, WAThe fatigue failure of the engine-to-transmission driveshaft adapter attachment bolt due to the application of inadequate torque on the bolt during assembly.NTSB CEN14LA307Accident · No injuriesLimited investigationFinal reportRotorway Exec 162F · Mt. Comfort, INThe pilot’s installation of an unauthorized main rotor belt and his subsequent failure to properly inspect the belt, which resulted in inadequate belt tension, the belt’s failure, and the subsequent loss of engine power.NTSB ERA14LA099Accident · Minor injuriesLimited investigationFinal reportBell 47D1 · Pell City, ALThe pilot’s use of an improper clutch engagement procedure, which resulted in clutch glazing, slippage, and, ultimately, the in-flight disengagement of the clutch and a loss of rotor rpm. Contributing to the accident were the installation of a light-weight…NTSB WPR14LA062Accident · No injuriesLimited investigationFinal reportHiller UH 12E · Chowchilla, CAThe failure of the torsional drive coupling, which resulted in a loss of drive to the main rotor system during low-altitude flight.NTSB WPR12FA191Accident · Serious injuriesField investigationFinal reportHughes 269C · Phoenix, AZA loss of tail rotor drive due to a fatigue failure of the main transmission pinion, which resulted in a loss of directional control during cruise flight.NTSB CEN12LA228Accident · Minor injuriesLimited investigationFinal reportEnstrom 280FX · Corpus Christi, TXThe failure of the bolt that retained the clutch drive rod end, which resulted in a loss of main rotor drive and a subsequent hard landing.NTSB CEN11LA305Accident · Minor injuriesLimited investigationFinal reportD & D Rotorway Exec · Massillon, OHThe excessive wear on the secondary shaft, from the inner bearing race, which resulted in the transmission clutch disengagement and a loss of power to the rotor system.NTSB ERA11LA216Accident · No injuriesLimited investigationFinal reportHiller UH-12E · Culpeper, VAMechanical failure of the transmission for reasons that could not be determined because the transmission could not be torn down.NTSB ERA11LA204Accident · No injuriesLimited investigationFinal reportRobinson R22 · Goshen, NYThe pilot’s failure to adhere to published preflight checklist limitations and procedures, resulting in excessive slack and subsequent failure of the power transmission belts and a total loss of rotor system drive.NTSB WPR11LA167Accident · No injuriesLimited investigationFinal reportRotorway A600 · Chandler, AZA design modification that changed the fasteners and components used to attach the main rotor drive pulley to the engine, which resulted in fatigue failure of those fasteners and a complete loss of power to the main rotor.NTSB ERA10LA361Accident · No injuriesLimited investigationFinal reportRobinson Helicopter R22 Beta · West Melbourne, FLSeparation of the main rotor drive belts due to maintenance personnel’s failure to adequately inspect the upper drive sheave prior to installing the belts.NTSB WPR10FA112Accident · No injuriesField investigationFinal reportEurocopter AS350 B3 · Reno, NVThe improper installation of the engine-to-main gear box flex coupling, which resulted in the failure of the flex coupling and a loss of power to the rotor system during takeoff. Contributing to the accident was the mechanic who removed the engine's failure…NTSB ERA10LA019Accident · Serious injuriesLimited investigationFinal reportRobinson R44 · La Belle, FLThe loss of main rotor rpm due to the failure of one or more of the drive belts for undetermined reasons.NTSB ANC09GA040Accident · No injuriesFinal reportRobinson Helicopter R44 · Iliamna, AKThe main rotor transmission mount design, which resulted in an in-flight vibration/oscillation, and damage to the helicopter during an emergency descent and hard landing. Contributing to the accident was the lack of information from the manufacturer regarding…NTSB CEN09TA060Accident · 1 fatalFinal reportBell OH-58C · Quitman, ARThe pilot’s failure to execute a proper autorotation during a forced landing after a loss of rotor rpm for undetermined reasons.NTSB CEN09CA026Accident · Minor injuriesData collectionFinal reportHolland Rotorway 162F · Rutland, SDThe loss of torque due to a failure of a transmission drivebelt and the pilot's delayed landing flare during the autorotation. Contributing to the accident was the dusk light condition and the corn crop.NTSB DFW08CA152Accident · Serious injuriesData collectionFinal reportRotorway 162F · Gonzales, TXfailure of the main rotor drive belt for undetermined reasons.NTSB DFW08CA147Accident · No injuriesData collectionFinal reportDowell Vaughn Exec 90 · Lafayette, COThe pilot's improper in-flight decision to continue flight after experiencing a loss of rotor RPM. Contributing to the accident were the pilot's low level of experience in helicopters and the leaking oil from the engine oil filler cap.NTSB ANC08FA053Accident · 4 fatalField investigationFinal reportEurocopter AS 350 B2 · Chickaloon, AKAn in-flight overtorque of the engine-to-transmission driveshaft resulting in disconnection of the main transmission from the engine. The overtorque likely occurred due to an in-flight main rotor blade contact with snow-covered terrain, precluding significant…NTSB CHI08CA105Accident · No injuriesData collectionFinal reportSchultz Mini 500 · Batavia, OHThe failure of the helicopter's centrifugal clutch during hover which led to the pilot's inability to maintain control of the craft and its subsequent impact with the ground.