# NTSB investigations: Accessory gear-boxes 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. ## Latest cases - [NTSB ERA24FA050](https://openairdocs.org/ntsb/ERA24FA050.md): Piper PA32R · Attalla, AL · Accident · 1 fatal · Class 3 · Field · Final report · Nov 27, 2023 · N4187Q · Destroyed > The undetected wear of both pawl retaining rivets of the left magneto impulse coupling and fatigue failure of one pawl retaining rivet, which led to cascading fractures of the second pawl retaining rivet, left gear retainer assembly, and gear teeth of… - [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 WPR23LA215](https://openairdocs.org/ntsb/WPR23LA215.md): Piper J3C-65 · Belfair, WA · Accident · Serious injuries · Class 3 · Limited · Final report · Jun 4, 2023 · N77583 · Substantial damage > The total loss of engine power due to the fatigue failure of the crankshaft accessory drive gear. - [NTSB ERA22LA268](https://openairdocs.org/ntsb/ERA22LA268.md): Wingren Norman Escapade · Brasstown, NC · Accident · No injuries · Class 3 · Limited · Final report · May 9, 2022 · N86RD · Substantial damage > The failure of the engine gearbox drive flange, which resulted in a nose gear collapse during the subsequent precautionary landing in tall grass. - [NTSB ERA22LA117](https://openairdocs.org/ntsb/ERA22LA117.md): Hughes 369D · Bel Air, MD · Accident · No injuries · Class 3 · Limited · Final report · Feb 9, 2022 · N9159F · Substantial damage > A loss of engine power due to bearing failures in the turbine section resulting from a fatigue fracture of the oil supply line that fed oil to the Nos. 6 and 7 bearings. The oil line failure led to rapid deterioration of the bearings from oil starvation.… - [NTSB CEN19LA156](https://openairdocs.org/ntsb/CEN19LA156.md): Rockwell S 2R · Oakes, ND · Accident · No injuries · Class 3 · Limited · Final report · May 25, 2019 · N4907X · Substantial damage > The failure of the helical cam gear of the engine assembly due to fatigue cracks in the gear teeth, which resulted in a total loss of engine power. - [NTSB WPR19LA029](https://openairdocs.org/ntsb/WPR19LA029.md): BKF Backcountry Supercub · Casper, WY · Accident · No injuries · Class 3 · Limited · Final report · Nov 19, 2018 · N59BK · Substantial damage > The seizure of two bearings in the reduction gearbox, resulting in the total loss of engine power. Contributing to the accident was a high descent rate which resulted in a hard landing. - [NTSB CEN18LA281](https://openairdocs.org/ntsb/CEN18LA281.md): Piper PA28 · Shreveport, LA · Accident · No injuries · Limited investigation · Final report · Jul 19, 2018 · N7080F · Substantial damage > The partial loss of engine power for reasons that could not be determined based on the available evidence. - [NTSB CEN16LA035](https://openairdocs.org/ntsb/CEN16LA035.md): Glimn Kitfox 2-3 · Escanaba, MI · Accident · Minor injuries · Limited investigation · Final report · Nov 3, 2015 · N93TG · Substantial damage > The airplane owner's inadequate maintenance and servicing of the propeller gearbox, which resulted in oil starvation, failure of the gearbox in flight, and a subsequent loss of propeller thrust. Contributing to the outcome was the airplane's low altitude at… - [NTSB WPR15LA248](https://openairdocs.org/ntsb/WPR15LA248.md): Sikorsky S 61A · Ironside, OR · Accident · Minor injuries · Limited investigation · Final report · Aug 20, 2015 · N1043T · Substantial damage > A loss of power to the No. 2 engine due to the failure of the accessory gearbox drivetrain. Also causal was the pilot’s inability to release the external longline due to the use of a safety wire across the coupling of the quick-disconnect mechanism, which… - [NTSB ERA14LA130](https://openairdocs.org/ntsb/ERA14LA130.md): Victor M Cordero RV-9A · Apopka, FL · Accident · Serious injuries · Limited investigation · Final report · Feb 23, 2014 · N19VC · Substantial damage > The failure of the propeller spline shaft, the drive disk adapter, and the propeller speed reduction unit (PSRU) input spline due to a lack of inspection and lubrication, which resulted in a total loss of propeller drive and a subsequent forced landing.… - [NTSB WPR13LA358](https://openairdocs.org/ntsb/WPR13LA358.md): Bell 206B · Chualar, CA · Accident · Minor injuries · Limited investigation · Final report · Aug 4, 2013 · N90146 · Substantial damage > Maintenance personnel's failure to properly tighten the bolts securing the main driveshaft to the transmission, which resulted in fatigue failure of the bolts and disconnection of the driveshaft during low-altitude flight. - [NTSB CEN13FA352](https://openairdocs.org/ntsb/CEN13FA352.md): Aero Commander 685 · Victoria, TX · Accident · Serious injuries · Field investigation · Final report · Jun 15, 2013 · N74CP · Substantial damage > Maintenance personnel's failure to secure the left engine idler pin during overhaul, which resulted in a catastrophic engine failure and subsequent forced landing. - [NTSB CEN12LA551](https://openairdocs.org/ntsb/CEN12LA551.md): Piper PA-24-260 · Holton, KS · Accident · Serious injuries · Limited investigation · Final report · Aug 17, 2012 · N8546P · Substantial damage > The mechanic's failure to adequately torque the right magneto attachment nuts, allowing the right magneto to come loose, which allowed engine oil to escape, causing the engine to seize. - [NTSB CEN12LA470](https://openairdocs.org/ntsb/CEN12LA470.md): Yamokoski William Glastar · Chicago, IL · Accident · Minor injuries · Limited investigation · Final report · Jul 22, 2012 · N4970Y · Substantial damage > Failure of the automotive engine's reduction gearbox while in cruise flight. - [NTSB ERA11FA512](https://openairdocs.org/ntsb/ERA11FA512.md): Heronimus Kevin A Glasair III · Falls of Rough, KY · Accident · 1 fatal · Field investigation · Final report · Sep 30, 2011 · N43KH · Substantial damage > The failure of the propeller power speed reduction unit, which resulted in a loss of engine power at low altitude. - [NTSB ERA10LA316](https://openairdocs.org/ntsb/ERA10LA316.md): Mcculloch Jerry RV-4 · Pageland, SC · Accident · Minor injuries · Limited investigation · Final report · Jun 17, 2010 · N418GM · Substantial damage > Maintenance personnel’s improper installation and inspection of the crankshaft idler gear, which resulted in a loss of engine power. - [NTSB ERA09LA490](https://openairdocs.org/ntsb/ERA09LA490.md): Piper PA-25-235 · Bainbridge, GA · Accident · No injuries · Limited investigation · Final report · Aug 27, 2009 · N7339Z · Substantial damage > A total loss of engine power due to the loss of camshaft timing as a result of the displacement of the idler gear assembly. - [NTSB CHI08LA274](https://openairdocs.org/ntsb/CHI08LA274.md): Sadler Vampire · Findlay, OH · Accident · Minor injuries · Limited investigation · Final report · Sep 3, 2008 · N333SV · Substantial damage > A total loss of engine power due to the failure of the reduction drive assembly as a result of excessive wear and high temperatures. Contributing to the accident were the pilot's lack of total experience in the airplane and the unsuitable terrain for a forced… ## 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", '010583')) ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC ``` This list as a web page: https://openairdocs.org/ntsb-findings/010583/cases --- 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.