NTSB investigations: Allison 250-C20 series

5 cases on aircraft whose registry engine model is Allison 250-C20 series, where the defining event was Dynamic rollover. 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.

Cases per year

20142026
NTSB investigations: Allison 250-C20 series per year, 2014–2026: 5 cases
20142
20161
20181
20241

Latest 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 x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('03020')
      AND EXISTS (SELECT 1 FROM 'https://openairdocs.org/data/latest/ntsb_events.parquet' e WHERE e.case_mkey = x.case_mkey AND e.aircrafts_position = x.position AND e.\"isDefiningEvent\" AND e.\"tier2Number\" = '231'))
  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.

NTSB ANC24LA012Accident · No injuriesClass 4 · LimitedFinal reportMcdonnell Douglas Helicopter 369E · Waialua, HIThe pilot's inability to maintain directional control after a skid got caught on a fence while he was maneuvering the helicopter for takeoff, which resulted in a dynamic roll-over.Jan 25, 2024 · N545PH · Substantial damageNTSB ERA19FA035Accident · 2 fatalField investigationFinal reportAerospatiale AS 355F2 · Beekmantown, NYThe pilot's failure to keep the helicopter clear of a utility pole while hovering with a tailwind, which resulted in a dynamic rollover into active power lines.Oct 30, 2018 · N372CA · DestroyedNTSB ERA16LA104Accident · Serious injuriesLimited investigationFinal reportBell 206 · Linden, NJThe pilot receiving instruction's failure to maintain helicopter control during the initial takeoff, which resulted in a dynamic rollover. Contributing to the accident was the flight instructor's inadequate remedial action due to his distraction by looking…Feb 6, 2016 · N206R · Substantial damageNTSB CEN15CA007Accident · Serious injuriesData collectionFinal reportBell 206B · Atlanta, ARThe pilot's inadequate preflight inspection when he did not remove a tie-down strap prior to takeoff, which resulted in a dynamic rollover.Oct 3, 2014 · N4426M · Substantial damageNTSB WPR14LA113Accident · No injuriesLimited investigationFinal reportBell 206 · Bountiful, UTThe pilots' inaccurate assessment of the snow depth on the landing zone, which resulted in a landing on snow deeper than that for which the helicopter was equipped and led to dynamic rollover.Feb 5, 2014 · N3211N · Substantial damage