# Oxygen system - Type: NTSB finding section - Path: [Aircraft](https://openairdocs.org/ntsb-findings/01) › [Aircraft systems](https://openairdocs.org/ntsb-findings/0102) › Oxygen system - NTSB code: 010235 - Cases: 8 - In the probable cause: 6 - Fatal cases: 4 - All cases: https://openairdocs.org/ntsb-findings/010235/cases.md - Cases with it in the probable cause: https://openairdocs.org/ntsb-findings/010235/cases.md?cause=1 - Page: https://openairdocs.org/ntsb-findings/010235 ## Cases per year (in the probable cause / all) - 2008: 1 / 1 - 2009: 2 / 2 - 2010: 0 / 1 - 2015: 1 / 1 - 2016: 1 / 1 - 2021: 0 / 1 - 2023: 1 / 1 ## Findings - [Oxygen system, general](https://openairdocs.org/ntsb-findings/01023500): 4 cases, 3 in the probable cause - [Crew oxygen system](https://openairdocs.org/ntsb-findings/01023510): 2 cases, 1 in the probable cause - [Passenger oxygen system](https://openairdocs.org/ntsb-findings/01023520): 1 cases, 1 in the probable cause - [Oxygen sys wiring](https://openairdocs.org/ntsb-findings/01023597): 1 cases, 1 in the probable cause ## Defining events in these cases - [Electrical system malf/failure](https://openairdocs.org/ntsb-events/332): 2 cases - [Miscellaneous/other](https://openairdocs.org/ntsb-events/900): 1 cases - [Medical event](https://openairdocs.org/ntsb-events/850): 1 cases - [Pressure/environ sys malf/fail](https://openairdocs.org/ntsb-events/331): 1 cases - [Loss of control in flight](https://openairdocs.org/ntsb-events/240): 1 cases - [Fire/smoke (non-impact)](https://openairdocs.org/ntsb-events/150): 1 cases - [Unknown or undetermined](https://openairdocs.org/ntsb-events/000): 1 cases ## Aircraft models (registry) - [Mooney M20TN](https://openairdocs.org/model/mooney-m20tn): 1 cases - [Cirrus Design SR22](https://openairdocs.org/model/cirrus-design-sr22): 1 cases - [Cessna 560](https://openairdocs.org/model/cessna-560): 1 cases - [Cessna 501](https://openairdocs.org/model/cessna-501): 1 cases - [Boeing 767-432ER](https://openairdocs.org/model/boeing-767-432er): 1 cases - [Boeing 767-200](https://openairdocs.org/model/boeing-767-200): 1 cases - [Boeing 757-222](https://openairdocs.org/model/boeing-757-222): 1 cases - [Beech B36TC](https://openairdocs.org/model/beech-b36tc): 1 cases ## Other findings in the same cases - [Hypoxia/anoxia](https://openairdocs.org/ntsb-findings/02012035) (Personnel issues): 3 cases - [Adequacy of policy/proc](https://openairdocs.org/ntsb-findings/04021015) (Organizational issues): 1 cases - [Policy/procedure, general](https://openairdocs.org/ntsb-findings/04021000) (Organizational issues): 1 cases - [Equip certification/testing](https://openairdocs.org/ntsb-findings/04012015) (Organizational issues): 1 cases - [Scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010) (Personnel issues): 1 cases - [Decision making/judgment](https://openairdocs.org/ntsb-findings/02041520) (Personnel issues): 1 cases - [Incorrect action selection](https://openairdocs.org/ntsb-findings/02041010) (Personnel issues): 1 cases - [Other loss of consciousness](https://openairdocs.org/ntsb-findings/02012055) (Personnel issues): 1 cases - [Impairment/incapacitation, general](https://openairdocs.org/ntsb-findings/02012000) (Personnel issues): 1 cases - [Fuel](https://openairdocs.org/ntsb-findings/01071010) (Aircraft): 1 cases ## Newest cases - [NTSB ERA23FA256](https://openairdocs.org/ntsb/ERA23FA256), Jun 4, 2023: Cessna 560 (N611VG), Montebello, VA, destroyed, 4 fatal. Probable cause: Pilot incapacitation due to loss of cabin pressure for undetermined reasons. Contributing to the accident was the pilot’s and owner/operator’s decision to operate the airplane without supplemental… - [NTSB CEN22FA021](https://openairdocs.org/ntsb/CEN22FA021), Oct 27, 2021: Beech B36TC (N75RM), Lena, WI, substantial damage, 1 fatal. Probable cause: Impairment and subsequent incapacitation of the pilot for reasons that could not be determined. The incapacitation resulted in a loss of engine power due to fuel starvation. Likely contributing was… - [NTSB CEN16LA197](https://openairdocs.org/ntsb/CEN16LA197), May 24, 2016: Cessna 501 (N804ST), Texarkana, AR, substantial damage. Probable cause: The pilot's failure to use supplemental oxygen as required during high-altitude flight, which resulted in his loss of consciousness following a loss of cabin pressurization. Contributing to the… - [NTSB ERA15LA349](https://openairdocs.org/ntsb/ERA15LA349), Sep 10, 2015: Mooney M20TN (N370MM), Atlantic City (Atlantic Ocean), substantial damage, 1 fatal. Probable cause: A loose oxygen line, which was not detected by maintenance personnel during a recent annual inspection, that allowed oxygen to escape and drain the oxygen canister more quickly than the pilot… - [NTSB ENG10IA029](https://openairdocs.org/ntsb/ENG10IA029), May 17, 2010: Boeing 757 (N510UA), Chantilly, VA, incident, minor damage. Probable cause: The ignition of the J5 power terminal located on the captain’s No. 1 windshield due to a loose electrical connection between the terminal connector lug and its respective terminal block. The loose… - [NTSB ENG09IA016](https://openairdocs.org/ntsb/ENG09IA016), Sep 8, 2009: Boeing 767 432ER (N840MH), St. Johns, Canada, incident, minor damage. Probable cause: Incorrect installation of a wire bundle, which contained wires for oxygen system, passenger address system and lavatory power, led to chafing of the wires on structure. The chafing eventually exposed… - [NTSB ERA09FA429](https://openairdocs.org/ntsb/ERA09FA429), Jul 31, 2009: Cirrus SR-22 (N581DS), Ravenswood, WV, destroyed, 1 fatal. Probable cause: The pilot's improper modification of the certified, on-board oxygen system, which resulted in incapacitation due to hypoxia, and the airplane's subsequent uncontrolled descent into terrain. - [NTSB DCA08MA076](https://openairdocs.org/ntsb/DCA08MA076), Jun 28, 2008: Boeing 767 (N799AX), San Francisco, CA, destroyed. Probable cause: The design of the supplemental oxygen system hoses and the lack of positive separation between electrical wiring and electrically conductive oxygen system components. The lack of positive separation… 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.