# Propeller governor - Type: NTSB finding subsection - Path: [Aircraft](https://openairdocs.org/ntsb-findings/01) › [Aircraft propeller/rotor](https://openairdocs.org/ntsb-findings/0104) › [Propeller system](https://openairdocs.org/ntsb-findings/010461) › Propeller governor - NTSB code: 01046122 - Cases: 16 - In the probable cause: 16 - Fatal cases: 3 - All cases: https://openairdocs.org/ntsb-findings/01046122/cases.md - Cases with it in the probable cause: https://openairdocs.org/ntsb-findings/01046122/cases.md?cause=1 - Page: https://openairdocs.org/ntsb-findings/01046122 ## Cases per year (in the probable cause / all) - 2008: 1 / 1 - 2009: 1 / 1 - 2011: 1 / 1 - 2012: 1 / 1 - 2013: 2 / 2 - 2015: 2 / 2 - 2016: 1 / 1 - 2017: 1 / 1 - 2018: 1 / 1 - 2019: 2 / 2 - 2021: 1 / 1 - 2023: 1 / 1 - 2024: 1 / 1 ## Defining events in these cases - [Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340): 6 cases - [Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342): 3 cases - [Loss of engine power (total)](https://openairdocs.org/ntsb-events/341): 3 cases - [Miscellaneous/other](https://openairdocs.org/ntsb-events/900): 1 cases - [Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330): 1 cases - [Runway excursion](https://openairdocs.org/ntsb-events/300): 1 cases - [Hard landing](https://openairdocs.org/ntsb-events/092): 1 cases ## Aircraft models (registry) - [WSK PZL Mielec M-18A](https://openairdocs.org/model/wsk-pzl-mielec-m-18a): 1 cases - [Socata TB200](https://openairdocs.org/model/socata-tb200): 1 cases - [Raytheon A36](https://openairdocs.org/model/raytheon-a36): 1 cases - [Mooney M20K](https://openairdocs.org/model/mooney-m20k): 1 cases - [Diamond Aircraft Ind DA 40](https://openairdocs.org/model/diamond-aircraft-ind-da-40): 1 cases - [Convair C-131B](https://openairdocs.org/model/convair-c-131b): 1 cases - [Cirrus Design SR22](https://openairdocs.org/model/cirrus-design-sr22): 1 cases - [Cessna 421C](https://openairdocs.org/model/cessna-421c): 1 cases - [Boeing A75N1(PT17)](https://openairdocs.org/model/boeing-a75n1-pt17): 1 cases - [Beech V35](https://openairdocs.org/model/beech-v35): 1 cases ## Other findings in the same cases - [Installation](https://openairdocs.org/ntsb-findings/02062035) (Personnel issues): 3 cases - [Oil](https://openairdocs.org/ntsb-findings/01071020) (Aircraft): 3 cases - [Not determined, general](https://openairdocs.org/ntsb-findings/05000000) (Not determined): 2 cases - [Scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010) (Personnel issues): 2 cases - [Powerplant parameters](https://openairdocs.org/ntsb-findings/01062050) (Aircraft): 2 cases - [Altitude](https://openairdocs.org/ntsb-findings/01062012) (Aircraft): 2 cases - [Equipment manufacture](https://openairdocs.org/ntsb-findings/04013010) (Organizational issues): 1 cases - [Rough terrain](https://openairdocs.org/ntsb-findings/03021015) (Environmental issues): 1 cases - [Use of equip/system](https://openairdocs.org/ntsb-findings/02063015) (Personnel issues): 1 cases - [Preflight inspection](https://openairdocs.org/ntsb-findings/02061510) (Personnel issues): 1 cases ## Newest cases - [NTSB CEN24LA187](https://openairdocs.org/ntsb/CEN24LA187), Feb 11, 2024: Aviat A1 (N122HU), Poole, NE, substantial damage. Probable cause: The non-certificated pilot’s failure to configure the airplane for takeoff, which resulted in a runway excursion. - [NTSB CEN24LA061](https://openairdocs.org/ntsb/CEN24LA061), Dec 8, 2023: Cessna 421C (N146TJ), McGregor, TX, substantial damage. Probable cause: The failure of the spring pin in the right propeller governor, which precluded the pilot from controlling the propeller pitch to maintain engine rpm, resulting in a loss of engine thrust, excessive… - [NTSB WPR21LA208](https://openairdocs.org/ntsb/WPR21LA208), May 26, 2021: Boeing A75N1(PT17) (N75016), Hollister, CA, substantial damage. Probable cause: The improper installation of a relief valve spring that was shorter than the standard spring length, which slowed the response of the propeller governor to change the pitch of the blades during… - [NTSB ERA19LA232](https://openairdocs.org/ntsb/ERA19LA232), Jul 19, 2019: Vans RV7 (N849GS), Ocean City, MD, substantial damage. Probable cause: The disconnection of the propeller governor control arm from the propeller governor due to a missing attachment bolt, which resulted in a partial loss of engine power during takeoff when the governor… - [NTSB ERA19LA096](https://openairdocs.org/ntsb/ERA19LA096), Feb 8, 2019: Convair C131 (N145GT), Atlantic Ocean (Atlantic Ocean), destroyed, 1 fatal. Probable cause: The captain's decision to continue with the flight with a malfunctioning left engine propeller control and the subsequent loss of engine power on both engines for undetermined reasons, which resulted… - [NTSB WPR18FA131](https://openairdocs.org/ntsb/WPR18FA131), May 2, 2018: American Air Racing Thunder Mustang (N352BT), Reno, NV, substantial damage, 1 fatal. Probable cause: The pilot's failure to properly secure the engine coolant pump pulley during recent maintenance, which resulted in a loss of the engine's lubrication, cooling, and propeller control systems, and a… - [NTSB ERA18LA021](https://openairdocs.org/ntsb/ERA18LA021), Nov 10, 2017: Socata TB200 (N207GT), Annapolis, MD, substantial damage. Probable cause: A loss of engine power for undetermined reasons after the disconnection of the propeller governor control due to inadequate securenment during maintenance. - [NTSB WPR16FA095](https://openairdocs.org/ntsb/WPR16FA095), Apr 21, 2016: Mooney M20K (N97119), Woodland, WA, substantial damage, 1 fatal. Probable cause: The pilot's delay in recognizing that the airplane was not performing as expected and aborting the takeoff, which resulted in collision with a berm beyond the end of the runway. Contributing to the… - [NTSB CEN15IA365](https://openairdocs.org/ntsb/CEN15IA365), Aug 16, 2015: Beech V35 (N2059W), Mount Vernon, OH, incident, no damage. Probable cause: The loosening of the flyweight due to the installation of an improperly hardened flyweight carrier, which resulted in the overspeed of the propeller and engine and the subsequent in-flight separation… - [NTSB CEN15LA298](https://openairdocs.org/ntsb/CEN15LA298), Jul 7, 2015: Cirrus Design SR22 (N422PB), Houston, TX, substantial damage. Probable cause: Maintenance personnel's improper installation of the propeller governor, which resulted in damage to the governor drive gear and its subsequent failure and a subsequent 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.