NTSB investigations: Allison 250-C20 series
20 cases on aircraft whose registry engine model is Allison 250-C20 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.
Cases per year
| 1984 | 1 |
|---|---|
| 1987 | 2 |
| 1992 | 1 |
| 1994 | 1 |
| 1995 | 1 |
| 1997 | 1 |
| 1999 | 2 |
| 2000 | 3 |
| 2001 | 1 |
| 2002 | 1 |
| 2003 | 1 |
| 2004 | 1 |
| 2006 | 2 |
| 2007 | 2 |
Where
Open the mapLatest 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_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 ('03020')
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" DESCRun 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 NYC07LA188Accident · No injuriesLimited investigationFinal reportBell 206B · Warrenton, VAThe flight instructor's failure to maintain adequate rotor rpm during touchdown.NTSB MIA07FA098Accident · 1 fatalField investigationFinal reportHughes 369A · Moulton, ALThe separation of a main rotor blade from its tension torsion bar for an undetermined reason.NTSB SEA06LA135Accident · No injuriesLimited investigationFinal reportHughes 369D · Moab, UTThe failure of the collective bungee support bracket due to non-compliance with a service information notice, which resulted in the pilot executing a precautionary autorotative landing. A contributing factor was the lack of suitable terrain for the landing.NTSB LAX06LA161Accident · Minor injuriesLimited investigationFinal reportBell 206B3 · Fallbrook, CAFailure of the engine to transmission drive shaft forward coupling due to overheating from lack of lubrication. The cause of the lack of lubrication was a result of improper maintenance. A factor was the trees.NTSB ATL04LA181Accident · Minor injuriesLimited investigationFinal reportHughes HU-369-D · Waynesboro, GAThe tail rotor assembly failed due to a fatigue fracture of the input gearshaft in the tail rotor gearbox assembly, which resulted in a loss of tail rotor control and subsequent collision with trees.NTSB FTW03LA080Accident · Serious injuriesLimited investigationFinal reportBell 206B · Putnam, TXthe pilot's failure to properly interpret and confirm a faulty tachometer instrument indication and his improper flare during the ensuing precautionary autorotation, which resulted in a hard landing. Also causal was the failure of the tachometer.NTSB SEA02LA137Accident · No injuriesLimited investigationFinal reportBell 206B · Elsie, ORThe shattering and separation of the forward right (pilot's) windscreen for undetermined reason(s).NTSB LAX01IA262Incident · No injuriesIncident investigationFinal reportMdhi 520N · Los Angeles, CAthe excitation of the first bending mode natural frequency of the aft tube assembly that is installed through the rotating NOTAR fan drive system. Contributing factors to the incident included the operator's maintenance practice of hand-sanding the pitch…NTSB MIA01FA006Accident · 1 fatalField investigationFinal reportAerospatiale AS-355-F2 · Burlington, NCThe mechanics failure to comply with manufacturers instructions for correction of a illuminated main rotor gearbox oil pressure warning light resulting in the helicopter being dispatched on a ferry flight with a failed main rotor gearbox oil pump, failure of…NTSB LAX01FA006Accident · Minor injuriesField investigationFinal reportMcDonnell Douglas 369E · Kernville, CAThe pilot's improper storage of personal items and his inadequate preflight inspection, which resulted in the unlatching of the left rear cabin door during flight and allowing a plastic garment bag to blow out and strike the tail rotor.NTSB SEA00LA197Accident · No injuriesLimited investigationFinal reportBell 206BII · Newhalem, WADebonding between the elastomeric material and the center plate of the transmission isolation mount.NTSB LAX00GA025Accident · 2 fatalFinal reportMcDonnell Douglas 500N · San Jose, CAThe pilot's in-flight loss of control due to the failure and separation of the forward thruster control cable telescoping sleeve ball swivel fitting, which resulted in a stuck thruster and the entry into an uncontrollable yaw/spin. Also causal was the…NTSB LAX99LA253Accident · Minor injuriesLimited investigationFinal reportHughes 369HS · Pacific Ocean (Pacific Ocean)The removal of the tail rotor blade abrasion strips by the use of an unapproved method by the maintenance personnel which resulted in the imbalance of the tail rotor blade assembly and subsequent separation of the 90-degree gear box; the pilot/mechanic's…NTSB FTW97FA352Accident · Minor injuriesField investigationFinal reportBell 407 · Grand Isle S108The tail rotor blade strike(s) that severed the aft portion of the tailboom, subsequently rendering the pilot with no tail rotor control while in cruise flight. A factor was the lack of suitable terrain for the forced autorotative landing.NTSB FTW95IA397Incident · No injuriesIncident investigationFinal reportMBB BO-105C · Lafayette, LAa short in the 'jam proof system' solenoid valve which prevented activation of the backup hydraulic system and resulting in a cyclic hardover. Factors were the contaminated hydraulic fluid and the resulting jammed actuator (longitudinal control slider).NTSB MIA94LA144Accident · Minor injuriesLimited investigationFinal reportBell 206B · St. Petersburg, FLThe failure of the number five bearing, shaft, or thomas coupling for undetermined reasons. Contributing to the accident was the pilot-in-command's delayed response in conducting the emergency procedure by not reducing the throttle to idle position, and…NTSB LAX93LA044Accident · No injuriesLimited investigationFinal reportHughes 369D · Carlsbad, CAFailure of the overrunning clutch assembly bearing for undetermined reasons.NTSB LAX87FA173Accident · Serious injuriesField investigationFinal reportHughes 369E · Palm Desert, CAThe helicopter dscndd uncontrolled & crashed in a residential area. After the acdnt, the plt said he agreed to orbit the residence of his pax. At the aprx 135 deg point of a left orbit, he felt 'a bang & severe vibration in the tail.' The plt lost drctnl ctl…NTSB NYC87LA058Accident · Minor injuriesLimited investigationFinal reportAgusta A109AII · So. Dartmouth, MAAgusta N300CC departed a helipad in front of claremont corp president's residence in south Dartmouth, Massachusetts. As the helicopter was hovering prior to moving forward, the tail rotor blade, s/n 124, failed. The tail rotor assembly and gearbox separated…NTSB LAX84FA405Accident · 2 fatalField investigationFinal reportHughes 369D · Mesa, AZThe helicopter experienced a main rotor drive system disconnect, an uncontrolled descent & subsequent inflight collision with terrain in a hilly desert area. This was the third & last in a planned series of marketing demo flts conducted for three USMC…