NTSB investigations: Lycoming VO-435-A1F

2 cases on aircraft whose registry engine model is Lycoming VO-435-A1F, 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

19862026

NTSB investigations: Lycoming VO-435-A1F per year, 1986–2026: 2 cases
1986	1
1989	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."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('42200') 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.\"mKey\" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('42200')
      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."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('42200')
    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 MIA89LA229Accident · No injuriesLimited investigationFinal reportBell 47G · Ponce, PRFailure of the aft tail rotor drive shaft.Aug 23, 1989 · N955B · Substantial damage NTSB LAX86LA283Accident · Serious injuriesLimited investigationFinal reportTexas Helicopter OH-13H/M · Valencia, CAThe pilot reported that he heard a loud bang and grinding noise from the engine/main transmission area while on a swath run. He stated that the main rotor RPM decayed immediately after he heard the noise. As the helicopter descended to about 50 feet above the…Jul 6, 1986 · N51856 · Substantial damage