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NTSB finding · Aircraft › Aircraft systems › Electrical power system

All 14 cases12 in the probable cause
Cases
14
In the probable cause
12 (86%)
Fatal cases
1
NTSB code
01022421

NTSB has coded findings and defining events since 2008. Earlier cases used its older occurrence and cause codes, so they aren’t counted here.

When and where

In green, cases where NTSB made it part of the probable cause; in gray, a factor or other finding. Findings are coded with the final report, often a year or more after the event, so the latest years are incomplete.

Cases per year

2008In the probable causeFactor only2026

Where

Open the map
Query with SQL
duckdb -csv -c "SELECT year(c.\"eventDate\") AS year, count(DISTINCT f.case_mkey) AS cases,
    count(DISTINCT f.case_mkey) FILTER (WHERE f.\"inProbableCause\") AS in_probable_cause
  FROM 'https://openairdocs.org/data/latest/ntsb_findings.parquet' f JOIN 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c ON c.\"mKey\" = f.case_mkey
  WHERE starts_with(f.\"findingCode\", '01022421') AND c.\"eventDate\" >= DATE '2000-01-01'
  GROUP BY 1
  ORDER BY 1"

Prints the counts as CSV. It reads the release’s Parquet files over HTTPS, so there’s nothing to download first. Install DuckDB to run it.

In the same cases

Defining events
Aircraft models

Aircraft matched to the registry by N-number and date.

Other findings
Query with SQL
duckdb -csv -c "WITH matched AS (SELECT DISTINCT case_mkey, aircrafts_position FROM 'https://openairdocs.org/data/latest/ntsb_findings.parquet' WHERE starts_with(\"findingCode\", '01022421'))
  SELECT * FROM (
  SELECT 'Defining event' AS kind, e.\"tier2Number\" AS code, max(e.\"eventTier2Name\") AS name, count(DISTINCT f.case_mkey) AS cases
  FROM matched f JOIN 'https://openairdocs.org/data/latest/ntsb_events.parquet' e ON e.case_mkey = f.case_mkey AND e.aircrafts_position = f.aircrafts_position AND e.\"isDefiningEvent\"
  WHERE e.\"tier2Number\" <> ''
  GROUP BY ALL
  UNION ALL
  SELECT 'Aircraft model', a.aircraft_model_code, any_value(concat_ws(' ', m.manufacturer, m.model)), count(DISTINCT f.case_mkey)
  FROM matched f JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = f.case_mkey AND a.position = f.aircrafts_position
  LEFT JOIN 'https://openairdocs.org/data/latest/faa_aircraft_model.parquet' m ON m.code = a.aircraft_model_code
  WHERE a.aircraft_model_code IS NOT NULL
  GROUP BY ALL
  UNION ALL
  SELECT 'Other finding', left(g.\"findingCode\", 8), max(g.\"tier4Name\"), count(DISTINCT g.case_mkey)
  FROM 'https://openairdocs.org/data/latest/ntsb_findings.parquet' g
  WHERE g.case_mkey IN (SELECT case_mkey FROM matched) AND NOT starts_with(g.\"findingCode\", '01022421') AND g.\"findingCode\" GLOB '[0-9][0-9]*'
  GROUP BY ALL
  )
  QUALIFY row_number() OVER (PARTITION BY kind ORDER BY cases DESC) <= 10
  ORDER BY kind, cases DESC"

Prints the counts as CSV. It reads the release’s Parquet files over HTTPS, so there’s nothing to download first. Install DuckDB to run it.

Newest cases · 14

NTSB CEN24LA056Accident · Minor injuriesClass 3 · LimitedFinal reportVans RV6 · Fordyce, ARThe pilot’s failure to attain a proper touchdown point following an unidentified electrical system failure and subsequent partial loss of engine power, which resulted in a runway overrun and impact with terrain. Contributing to the accident was the pilot’s…Dec 5, 2023 · N600VS · Substantial damageNTSB ERA23LA064Accident · No injuriesClass 3 · LimitedFinal reportBeech 95-B55 (T42A) · Athens, GAThe operator’s and the pilot’s continued operation of the airplane with a known electrical problem, resulting in a loss of electrical power and a gear-up landing.Nov 3, 2022 · N101DC · Substantial damageNTSB ERA18TA263Accident · Minor injuriesFinal reportZenith CH 750 · DeLeon Springs, FLThe pilot's operation of the airplane with the alternator switch in the off position, which allowed the selected battery to discharge and resulted in an ignition system failure and a total loss of engine power.Sep 23, 2018 · N752VK · Substantial damageNTSB CEN18LA097Accident · No injuriesLimited investigationFinal reportPiper PA 24-260 · Fargo, NDThe pilot's failure to use the published emergency procedures to manually extend the landing gear when an electrical failure precluded normal extension of the landing gear, resulting in the gear collapse during landing. Contributing to the accident was the…Feb 8, 2018 · N9360P · Substantial damageNTSB ERA16LA305Accident · No injuriesLimited investigationFinal reportDayton A Babcock Storm · Eustis, FLThe pilot's failure to maintain directional control during an aborted takeoff. Contributing to the accident were the loss of engine power due to a malfunctioning alternator, which precipitated the off-field landing, and the pilot’s decision to attempt to take…Aug 20, 2016 · N516VB · Substantial damageNTSB ERA14LA252Accident · No injuriesLimited investigationFinal reportCessna 182 · Elkton, MDThe pilot’s failure to attain the proper touchdown point during a no-flap landing to a wet, down-sloping runway, and the airplane's dynamic hydroplaning after touchdown, which resulted in a runway overrun. Contributing to the accident was a total loss of…May 21, 2014 · N182PJ · Substantial damageNTSB DCA14CA043Accident · No injuriesData collectionFinal reportGeneral Atomics MQ-9 · Point Loma, CAintentional controlled ditching of the aircraft due to failure of the starter/generator supplying electrical power to the aircraft.Jan 27, 2014 · CBP-159 · DestroyedNTSB WPR13LA237Accident · No injuriesLimited investigationFinal reportPiper PA-32R-301T · Chandler, AZThe failure of the alternator and/or battery, which prevented the operation of the landing gear extension system and resulted in the nose landing gear collapsing during the landing roll.May 19, 2013 · N8197W · Substantial damageNTSB ERA12LA450Accident · No injuriesLimited investigationFinal reportBeech A36 · Johns Island, SCThe pilot's failure to complete the manual emergency gear extension after a loss of electrical power. Contributing to the accident was the pilot's decision to delegate the landing gear extension to a non-pilot-rated passenger.Jul 9, 2012 · N6672B · Substantial damageNTSB CEN12FA251Accident · 1 fatalField investigationFinal reportCirrus Design SR22 · Newcomerstown, OHThe pilot’s loss of airplane control in instrument meteorological conditions due to his distraction by electrical system anomalies, which resulted in an uncontrolled descent. The reason for the electrical system anomalies could not be determined.Apr 21, 2012 · N110EB · Substantial damage
See all 14 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\", '01022421'))
  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.