# Oil system - Type: NTSB finding subsection - Path: [Aircraft](https://openairdocs.org/ntsb-findings/01) › [Aircraft power plant](https://openairdocs.org/ntsb-findings/0105) › [Engine (turbine/turboprop)](https://openairdocs.org/ntsb-findings/010572) › Oil system - NTSB code: 01057261 - Cases: 16 - In the probable cause: 14 - Fatal cases: 1 - All cases: https://openairdocs.org/ntsb-findings/01057261/cases.md - Cases with it in the probable cause: https://openairdocs.org/ntsb-findings/01057261/cases.md?cause=1 - Page: https://openairdocs.org/ntsb-findings/01057261 ## Cases per year (in the probable cause / all) - 2009: 1 / 1 - 2011: 0 / 1 - 2012: 1 / 1 - 2013: 2 / 2 - 2014: 2 / 2 - 2015: 2 / 2 - 2017: 2 / 2 - 2018: 1 / 1 - 2019: 1 / 1 - 2023: 1 / 1 - 2024: 1 / 2 ## Defining events in these cases - [Loss of engine power (total)](https://openairdocs.org/ntsb-events/341): 10 cases - [Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340): 3 cases - [Uncontained engine failure](https://openairdocs.org/ntsb-events/343): 1 cases - [Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342): 1 cases - [Pressure/environ sys malf/fail](https://openairdocs.org/ntsb-events/331): 1 cases ## Aircraft models (registry) - [Eurocopter EC 130 B4](https://openairdocs.org/model/eurocopter-ec-130-b4): 1 cases - [Thrush S2R-G10](https://openairdocs.org/model/thrush-s2r-g10): 1 cases - [Robinson Helicopter R44](https://openairdocs.org/model/robinson-helicopter-r44): 1 cases - [Eurocopter Deutschland MBB-BK 117 C-2](https://openairdocs.org/model/eurocopter-deutschland-mbb-bk-117-c-2): 1 cases - [Gulfstream-Schweizer A/C GULFSTREAM AM G-164B](https://openairdocs.org/model/gulfstream-schweizer-a-c-gulfstream-am-g-164b): 1 cases - [Grumman Acft ENG Cor-Schweizer G-164A](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164a): 1 cases - [Garlick Helicopters OH-58C](https://openairdocs.org/model/garlick-helicopters-oh-58c): 1 cases - [MD Helicopters 369FF](https://openairdocs.org/model/md-helicopters-369ff): 1 cases - [Bell 407](https://openairdocs.org/model/bell-407): 1 cases - [Bell 206-L4](https://openairdocs.org/model/bell-206-l4): 1 cases ## Other findings in the same cases - [Oil](https://openairdocs.org/ntsb-findings/01071020) (Aircraft): 5 cases - [Turbine section](https://openairdocs.org/ntsb-findings/01057250) (Aircraft): 4 cases - [Decision making/judgment](https://openairdocs.org/ntsb-findings/02041520) (Personnel issues): 3 cases - [Compressor section](https://openairdocs.org/ntsb-findings/01057230) (Aircraft): 3 cases - [Engine (turbine/turboprop), general](https://openairdocs.org/ntsb-findings/01057200) (Aircraft): 3 cases - [Scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010) (Personnel issues): 2 cases - [Debris/dirt/foreign object](https://openairdocs.org/ntsb-findings/03022055) (Environmental issues): 1 cases - [Hidden/submerged object](https://openairdocs.org/ntsb-findings/03022052) (Environmental issues): 1 cases - [Pole](https://openairdocs.org/ntsb-findings/03022010) (Environmental issues): 1 cases - [Aircraft control](https://openairdocs.org/ntsb-findings/02063040) (Personnel issues): 1 cases ## Newest cases - [NTSB CEN24LA239](https://openairdocs.org/ntsb/CEN24LA239), Jun 17, 2024: Thrush S2R (N529KC), Hebron, ND, substantial damage. Probable cause: Foreign object debris in the Negative Torque Sensing (NTS) system check valve, which impeded the flow of oil to the NTS system and the propeller governor (PG) reset piston, resulting in a total loss… - [NTSB WPR24FA132](https://openairdocs.org/ntsb/WPR24FA132), Apr 26, 2024: Bell 206-L4 (N988B), Anaconda, MT, destroyed, 1 fatal. Probable cause: A total loss of engine power due to a loss of cooling oil to the turbine-to-compressor coupling shaft and subsequent fracture of the shaft at an altitude too low for the pilot to complete a… - [NTSB WPR24LA041](https://openairdocs.org/ntsb/WPR24LA041), Nov 21, 2023: Bell OH-58A (N158TR), Brawley, CA, substantial damage. Probable cause: A total loss of engine power due to the failure of the No. 8 bearing and the subsequent failure of the scavenge oil pump. - [NTSB CEN19LA231](https://openairdocs.org/ntsb/CEN19LA231), Jul 21, 2019: Ayres S2R (N766BF), Breckenridge, MI, substantial damage. Probable cause: A total loss of engine power due to a lack of oil in the engine. The source of the inflight oil leak could not be determined based on the available information. - [NTSB WPR18LA269](https://openairdocs.org/ntsb/WPR18LA269), Sep 18, 2018: Robinson R44 (N632NV), Wahiawa, HI, substantial damage. Probable cause: 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… - [NTSB WPR17LA133](https://openairdocs.org/ntsb/WPR17LA133), Jun 27, 2017: Eurocopter EC 130 B4 (N151GC), Boulder City, NV, substantial damage. Probable cause: A loss of engine power due to the failure of the manufacturer to reinstall the oil filter after it was removed for inspection, which led to coke pollution that obstructed the oil jet and resulted in… - [NTSB CEN17IA094](https://openairdocs.org/ntsb/CEN17IA094), Jan 27, 2017: Eurocopter Deutschland MBB BK 117 C-2 (N911MK), Sioux Falls, SD, incident, minor damage. Probable cause: The gas generator rear bearing oil scavenge line blocked with coke, which resulted in a failed rear bearing due to an excess of oil lubrication. Contributing to the incident was the operator not… - [NTSB ERA15LA280](https://openairdocs.org/ntsb/ERA15LA280), Jul 24, 2015: MD Helicopter 369FF (N5842Z), Vega Baja, PR, substantial damage. Probable cause: A total loss of engine power due to insufficient lubrication to the engine's No. 2 bearing, which resulted in the failure of the bearing and a subsequent forced landing. - [NTSB ERA15LA138](https://openairdocs.org/ntsb/ERA15LA138), Feb 15, 2015: Bell 206 (N3176L), Sevierville, TN, substantial damage. Probable cause: An uncontained engine failure, which resulted from insufficient lubrication of the No. 4 bearing due to carbon buildup on the filter screen of the bearing's oil supply nozzle. - [NTSB ERA14LA368](https://openairdocs.org/ntsb/ERA14LA368), Jul 25, 2014: Gulfstream-Schweizer A/C G-164B (N425LS), Bonifay, FL, substantial damage. Probable cause: A partial blockage of the No. 2 bearing oil nozzle jet by bearing material, which resulted in oil starvation and the subsequent failure of the No. 2 bearing and total loss of engine power. NTSB has coded findings and defining events since 2008; earlier cases used its older occurrence and cause codes and aren't counted. Findings: https://openairdocs.org/ntsb-findings.md. Defining events: https://openairdocs.org/ntsb-events.md. Phases of flight: https://openairdocs.org/ntsb-phases.md. Every investigation, filtered by finding, event, phase, state, year or model: https://openairdocs.org/ntsb.md (for example ?state=MI&fatal=1). NTSB's definitions: Accident and incident, 49 CFR 830.2 (https://www.ecfr.gov/current/title-49/subtitle-B/chapter-VIII/part-830/subpart-A/section-830.2), CICTT occurrence categories (PDF) (https://www.ntsb.gov/safety/data/Documents/datafiles/OccurrenceCategoryDefinitions.pdf), CICTT phases of flight (PDF) (https://www.ntsb.gov/safety/data/Documents/datafiles/PhaseofFlightDefinitions.pdf), and NTSB coding manual, before 2008 (PDF) (https://www.ntsb.gov/GILS/Documents/codman.pdf). NTSB publishes no definitions for its findings, only their names. --- 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.