NTSB finding section · Aircraft › Aircraft systems

Cases
65
In the probable cause
56 (86%)
Fatal cases
7
NTSB code
010229

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
Cases with Hydraulic power system per year: 65 cases
20086
20098
20104
20116
20124
20132
20146
20154
20162
20172
20183
20192
20205
20214
20223
20232
20242
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\", '010229') 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.

Subsections · 12

Query with SQL
duckdb -csv -c "SELECT left(f.\"findingCode\", 8) AS code, max(f.\"tier4Name\") AS name,
    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
  WHERE starts_with(f.\"findingCode\", '010229') AND f.\"findingCode\" GLOB '[0-9][0-9]*'
  GROUP BY 1
  ORDER BY cases DESC, code"

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

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\", '010229'))
  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\", '010229') 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 · 65

NTSB WPR24LA157Accident · No injuriesClass 3 · LimitedFinal reportCessna P210 · Daggett, CAThe pilot’s failure to detect the tripped alternator circuit breaker in flight, which resulted in a drained battery that prevented the landing gear from fully extending to the down-and-locked position. Contributing to the accident was the improperly installed…May 16, 2024 · N4769K · Substantial damageNTSB DCA24LA095Incident · No injuriesClass 2 · LimitedFinal reportBoeing 737-823 · Dallas, TXImproper maintenance due to human error during a braking system modification diminished braking performance. Contributing to the diminished braking performance was the lack of a functional check to verify the flexible hydraulic hoses and transducer wiring…Feb 11, 2024 · N991AN · Minor damageNTSB DCA24FA002Accident · No injuriesClass 2 · FieldFinal reportBoeing 757-236 · Chattanooga, TNThe failure of the alternate gear extension system, which prevented the landing gear from being lowered. The cause of the system failure was a broken wire, due to tensile overload, between the alternate gear extend switch and the alternate extension power…Oct 5, 2023 · N977FD · Substantial damageNTSB ERA23LA202Accident · No injuriesClass 3 · LimitedFinal reportRockwell International 112 · Miami, FLFailure of the right main landing gear due to inadequate hydraulic pressure as result of a torn O-ring that was installed on the hydraulic pack’s check valve during overhaul.Apr 18, 2023 · N12RX · Substantial damageNTSB WPR22LA341Accident · No injuriesClass 3 · LimitedFinal reportCessna 750 · Mesa, AZThe pilot’s improper decision to depart on the accident flight with a known hydraulic leak, resulting in an in-flight hydraulic system failure, and the pilot’s attempt to land during an unstabilized approach, which resulted in a loss of control during the…Sep 7, 2022 · N15TZ · Substantial damageNTSB CEN22LA378Accident · No injuriesClass 3 · LimitedFinal reportCessna 210B · Clinton, ARA fatigue crack in the hydraulic actuator, which resulted in the loss of hydraulic fluid and the pilot’s inability to fully extend the landing gear.Aug 9, 2022 · N9637X · Substantial damageNTSB ERA22LA148Accident · No injuriesClass 3 · LimitedFinal reportCessna 525 · Middle River, MDAnd undetermined failure of the brake system. Contributing to the accident was the failure of the pilots to locate and operate the emergency brake control, which resulted in a runway excursion and collision with terrain and an object.Mar 7, 2022 · N22AU · Substantial damageNTSB ERA22LA005Accident · No injuriesClass 4 · LimitedFinal reportCessna 210 · Columbia, SCA failure of the landing gear hydraulic power pack for reasons that could not be determined.Oct 5, 2021 · N6318B · Substantial damageNTSB DCA21LA229Accident · Serious injuriesClass 4 · LimitedFinal reportBoeing 767-332 · Seattle, WAThe flightcrew’s failure to set the hydraulic panel correctly during the execution of the pushback checklist, and when the hydraulic panel setting was corrected, that resulted in the airplane coming to a sudden stop and a flight attendant receiving a serious…Sep 1, 2021 · N196DN · No damageNTSB WPR21LA323Accident · No injuriesClass 3 · LimitedFinal reportCessna 177RG · Albuquerque, NMThe failure of the nose gear hydraulic flex line, which resulted in a loss of hydraulic fluid which prevented the main landing gear from fully extending and locking into place during landing.Aug 15, 2021 · N8029G · Substantial damage
See all 65 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\", '010229'))
  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.