Fatal NTSB investigations: Lycoming T-53 series

5 cases on aircraft whose registry engine model is Lycoming T-53 series, where the first occurrence was “Airframe/component/system failure/malfunction”. Aircraft are matched to the registry by N-number and event date, checked against the reported serial number, make and model, so older matches can be wrong.

Defining event

Finding

Phase of flight

Aircraft model

Cases per year

19842026

Fatal NTSB investigations: Lycoming T-53 series per year, 1984–2026: 5 cases
1984	1
1990	1
1993	1
1997	1
2001	1

Where

Open the map

Latest cases

Query with SQL

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."highestInjuryLevel" = 'Fatal' AND c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41552', '41549', '41587') AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o WHERE o.case_mkey = x.case_mkey AND o.aircrafts_position = x.position AND o."occurrenceNumber" = 1 AND o."occurrenceCode" = 130)) ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC

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.\"highestInjuryLevel\" = 'Fatal'
    AND c.\"mKey\" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41552', '41549', '41587')
      AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o WHERE o.case_mkey = x.case_mkey AND o.aircrafts_position = x.position AND o.\"occurrenceNumber\" = 1 AND o.\"occurrenceCode\" = 130))
  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.

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."highestInjuryLevel" = 'Fatal'
  AND c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41552', '41549', '41587')
    AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o WHERE o.case_mkey = x.case_mkey AND o.aircrafts_position = x.position AND o."occurrenceNumber" = 1 AND o."occurrenceCode" = 130))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC

Run it at the DuckDB prompt, or in any tool that reads Parquet over HTTPS. More ways to query the release are on Use the data.

NTSB SEA01LA046Accident · 1 fatalLimited investigationFinal reportWestern International UH-1H · Darby, MTInflight loss of a tail rotor pitch change link-to-blade grip attach bolt, resulting partial loss of tail rotor control, and subsequent entanglement of the helicopter's external load cable with a tree during emergency descent. Factors included the pilot's…Feb 7, 2001 · N205GL · Substantial damage NTSB SEA97FA196Accident · 1 fatalField investigationFinal reportSouthern Aero UH-1B · Skykomish, WAA fatigue fracture in the main rotor mast, which resulted in an in flight separation of the main rotor from the helicopter. Contributing to the accident was insufficient Federal Aviation Administration airworthiness standards and requirements for the aircraft.Aug 27, 1997 · N896W · Substantial damage NTSB ANC93FA056Accident · 1 fatalField investigationFinal reportBell 204B · Copper Harbor, AKFatigue failure of the tail rotor gearbox, and improper helicopter operations being conducted by the operator resulting in repetitive at and over maximum loads. Factors in the accident were: material defect of the tail rotor gear box (inadequate quality…May 2, 1993 · N204AQ · Destroyed NTSB ATL90FA100Accident · 1 fatalField investigationFinal reportBell 205A-1 · Moncks Corner, SCThe in-flight separation of the main rotor because of the failure of a pillow block bolt, and the failure of the operator/repair station to follow the overhaul procedures.Apr 20, 1990 · N67HJ · Destroyed NTSB MIA84FA166Accident · 1 fatalField investigationFinal reportBell UH-1B · Clermont, FLThe plt was not aware that two ground attendants were riding the cable during a logging operation when there was an accidental cable release & the attendants fell to the ground. Examination of the acfts hook did not reveal a system failure or malfunction.…May 10, 1984 · N2252A · No damage