# NTSB investigations: Allison 250-C20B A list on [Allison 250-C20B](https://openairdocs.org/engine/allison-250-c20b.md). Matched to the registry by N-number and event date, newest first. - [NTSB WPR26FA054](https://openairdocs.org/ntsb/WPR26FA054.md): Hughes 369D · Pryor, OK · Accident · 1 fatal · Class 3 · Field · Preliminary report · Dec 5, 2025 · N161LA · Substantial damage > On December 5, 2025, about 0858 central standard time, a Hughes 369D, N161LA, was substantially damaged when it was involved in an accident near Pryor, Oklahoma. The pilot was fatally injured. The helicopter was operated as a Title 14 Code of Federal… - [NTSB CEN25FA307](https://openairdocs.org/ntsb/CEN25FA307.md): Hughes 369D · West Alton, MO · Accident · 2 fatal · Class 3 · Field · Final report · Aug 7, 2025 · N173AL · Destroyed > The pilot’s failure to maintain helicopter clearance from the powerline during the powerline maintenance operation for reasons that could not be determined. - [NTSB ERA23LA293](https://openairdocs.org/ntsb/ERA23LA293.md): Hughes 369D · Waldorf, MD · Accident · Minor injuries · Class 3 · Limited · Final report · Jul 9, 2023 · N5027P · Substantial damage > Fatigue failure of the overrunning clutch outer race and a subsequent inflight loss of power due to abnormal bending loads as a result of improper reassembly of the clutch subassembly following maintenance and the presence of microcracks on the clutch’s outer… - [NTSB GAA23WA214](https://openairdocs.org/ntsb/GAA23WA214.md): Bell 206B · Thetford Mines, Canada · Accident · No injuries · Class 5 · Foreign · Jun 23, 2023 · N717LM · Substantial damage - [NTSB CEN22LA351](https://openairdocs.org/ntsb/CEN22LA351.md): Bell Helicopter Textron 206B · Arcadia, IA · Accident · Minor injuries · Class 3 · Limited · Final report · Aug 1, 2022 · N169AA · Substantial damage > Maintenance personnel’s failure to properly torque a fuel control unit B-nut, which resulted in a loss of engine power at low altitude and an impact with terrain. - [NTSB ERA22LA330](https://openairdocs.org/ntsb/ERA22LA330.md): Bell 206B · Kenton, OH · Accident · No injuries · Class 3 · Limited · Final report · Jul 21, 2022 · N39MK · Substantial damage > The pilot’s inadequate fuel management, which resulted in fuel exhaustion and a loss of engine power. - [NTSB ERA22LA342](https://openairdocs.org/ntsb/ERA22LA342.md): Messerschmitt-Boelkow-Blohm BO_105S · Daytona Beach, FL · Accident · No injuries · Class 4 · Limited · Final report · Jun 30, 2022 · N160TH · Substantial damage > The pilot’s rapid reduction of collective following an in-flight loss of control while lifting from a dolly resulting in a hard landing. Contributing to the loss of control was the pilot’s likely inadequate left anti-torque control pedal input during initial… - [NTSB CEN21LA102](https://openairdocs.org/ntsb/CEN21LA102.md): Hughes 369D · Tuckers Crossing, MS · Accident · 1 fatal · Class 3 · Limited · Final report · Dec 29, 2020 · N103SU · Destroyed > The pilot’s loss of helicopter control when the external saw contacted trees during an attempted emergency landing due to a main rotor transmission oil pressure warning. The reason that the pilot did not release the external saw from the helicopter during the… - [NTSB GAA19CA457](https://openairdocs.org/ntsb/GAA19CA457.md): Bell 206 · Dukedom, TN · Accident · Minor injuries · Data collection · Final report · Jul 27, 2019 · N454MS · Substantial damage > The pilot's failure to maintain clearance from wires during an agricultural application flight. - [NTSB GAA19CA186](https://openairdocs.org/ntsb/GAA19CA186.md): Bell 206 · Valley Center, CA · Accident · Serious injuries · Data collection · Final report · Mar 29, 2019 · N83181 · Substantial damage > The ground crew’s attachment of the load fill hose to the helicopter without telling the pilot, which resulted in a loss of helicopter control during takeoff. - [NTSB WPR18CA100](https://openairdocs.org/ntsb/WPR18CA100.md): Hughes 369D · Pacific Ocean, Marshall Islands · Accident · Minor injuries · Data collection · Final report · Feb 19, 2018 · N501VS · Substantial damage > An in-flight mechanical malfunction with the helicopter, which necessitated a ditching in the ocean. The reason for the malfunction could be determined because the helicopter sank and was not recovered. - [NTSB ERA17WA060](https://openairdocs.org/ntsb/ERA17WA060.md): Agusta A109A II · Varese, Italy · Accident · 1 fatal · Foreign investigation · Nov 19, 2016 · N109W · Destroyed > On November 19, 2016, at 1316 universal coordinated time, an Augusta A109 A II, N109W, was destroyed when it impacted terrain while navigating near Varese, Italy. An Italian passenger was fatally injured and the Italian certificated pilot and Swiss passenger… - [NTSB CEN17FA012](https://openairdocs.org/ntsb/CEN17FA012.md): Fairchild Hiller FH 1100 · Lino Lakes, MN · Accident · 2 fatal · Field investigation · Final report · Oct 6, 2016 · N4035G · Destroyed > The separation of the main rotor assembly due to mast bumping. - [NTSB WPR16FA072](https://openairdocs.org/ntsb/WPR16FA072.md): Bell 206B · Honolulu, HI · Accident · 1 fatal · Field investigation · Final report · Feb 18, 2016 · N80918 · Substantial damage > The in-flight failure of the engine-to-transmission drive shaft due to improper maintenance, which resulted in low main rotor rpm and a subsequent hard landing to water. - [NTSB WPR13CA406](https://openairdocs.org/ntsb/WPR13CA406.md): Hughes 369D · Kalalau, HI · Accident · Minor injuries · Data collection · Final report · Sep 12, 2013 · N519PA · Substantial damage > The entanglement of a tarp in the helicopter's main rotor from a nearby trash bundle. - [NTSB CEN13LA487](https://openairdocs.org/ntsb/CEN13LA487.md): Bell 206B · Albers, IL · Accident · No injuries · Limited investigation · Final report · Aug 10, 2013 · N804LA · Substantial damage > Fuel contamination, which resulted in the loss of engine power. - [NTSB CEN13CA281](https://openairdocs.org/ntsb/CEN13CA281.md): Hughes 369D · Camdenton, MO · Accident · No injuries · Data collection · Final report · May 15, 2013 · N725M · Substantial damage > The piece of wood/tree that contacted the main rotor blade during the low altitude tree-trimming flight. - [NTSB ERA13LA057](https://openairdocs.org/ntsb/ERA13LA057.md): Hughes 369D · Corning, NY · Accident · 2 fatal · Limited investigation · Final report · Nov 15, 2012 · N369AW · Substantial damage > The pilot’s failure to maintain adequate altitude while conducting a power line aerial observation flight, which resulted in an in-flight collision with wires. Contributing to the accident was the pilot’s lack of total experience in the type of operation. - [NTSB ERA12CA304](https://openairdocs.org/ntsb/ERA12CA304.md): Bell 206B · Hershey, PA · Accident · Serious injuries · Data collection · Final report · Apr 27, 2012 · N16EP · Substantial damage > The pilot's diverted attention while performing aerial application at low altitude, which resulted in controlled flight into terrain. Contributing to the accident was the pilot’s failure to adjust the control friction to the position he was accustomed. - [NTSB CEN12LA141](https://openairdocs.org/ntsb/CEN12LA141.md): Bell 206B · Irving, TX · Accident · No injuries · Limited investigation · Final report · Jan 22, 2012 · N555NB · Substantial damage > A total loss of engine power due to fuel exhaustion as a result of the pilot’s inadequate fuel planning. - [NTSB WPR10CA364](https://openairdocs.org/ntsb/WPR10CA364.md): Bell 206 B II · Big Bear City, CA · Accident · No injuries · Data collection · Final report · Jul 24, 2010 · N788BD · Substantial damage > The pilot's failure to maintain directional control during the landing approach. - [NTSB ERA09LA031](https://openairdocs.org/ntsb/ERA09LA031.md): Hughes 369D · Carroll Township, PA · Accident · Serious injuries · Limited investigation · Final report · Oct 30, 2008 · N606AS · Substantial damage > A total loss of engine power due to the improper assembly of the compressor discharge tubes to the combustion liner. - [NTSB MIA07LA148](https://openairdocs.org/ntsb/MIA07LA148.md): Bell 206B3 · Lakeland, FL · Accident · No injuries · Limited investigation · Final report · Sep 5, 2007 · N267MW · Substantial damage > The failure of company maintenance personnel to replace the tail rotor drive shafts following tail rotor blade damage in 1999, the failure of maintenance personnel to replace the tail rotor drive shafts in 2004, following their knowledge that the tail rotor… - [NTSB MIA06LA126](https://openairdocs.org/ntsb/MIA06LA126.md): Fairchild Hiller FH-1100 · Navarre, FL · Accident · No injuries · Limited investigation · Final report · Jun 8, 2006 · N4035G · Substantial damage > The inadequate manufacturing of the plates of the tail rotor tension-torsion bar assembly resulting in fatigue failure. - [NTSB MIA05CA160](https://openairdocs.org/ntsb/MIA05CA160.md): Bell 206B3 · Titusville, FL · Accident · No injuries · Data collection · Final report · Sep 23, 2005 · N39MK · Substantial damage > The flight instructor's improper flare resulting in a hard landing and main rotor contact with tail boom. - [NTSB BFO94LA155](https://openairdocs.org/ntsb/BFO94LA155.md): Hughes 369D · Butler, PA · Accident · No injuries · Limited investigation · Final report · Aug 28, 1994 · N5027P · Substantial damage > The malfunction of the emergency fuel vent and the exhaustion of the fuel supply which resulted in the loss of engine power. - [NTSB LAX94LA076](https://openairdocs.org/ntsb/LAX94LA076.md): Hughes 369D · Waimea, Kauai, HI · Accident · No injuries · Limited investigation · Final report · Dec 22, 1993 · N115HD · Substantial damage > An inadequate engine compressor cleaning procedure specified in the manufacturer's service letter, which resulted in the total loss of engine power due to contamination, blockage, and collapse of the fuel nozzle inlet screen. Factors in the accident were: the… - [NTSB DEN85LA079](https://openairdocs.org/ntsb/DEN85LA079.md): Hiller FH-1100 · Steamboat Sprng, CO · Accident · No injuries · Limited investigation · Final report · Feb 18, 1985 · N4035G · Substantial damage > Purpose of the flt was to test the helicopter after an annual inspection. The plt flew the acft for aprx 1 hour from the left seat with the acft owner in the right seat before the owner deplaned the acft and the plt moved into the right seat. Plt stated that… - [NTSB NYC84LA204](https://openairdocs.org/ntsb/NYC84LA204.md): Hughes 500D · Bedford, PA · Accident · No injuries · Limited investigation · Final report · Jun 7, 1984 · N5106Y · Substantial damage > According to the plt, the helicopter took off with under 200 lbs of fuel indicating on the fuel gage. Fifteen minutes after takeoff at 125 ft AGL the engine out warning system indicated an engine failure. The acft began to rotate about its vetical axis and… - [NTSB FTW80DA117](https://openairdocs.org/ntsb/FTW80DA117.md): Bell 206B · Intracstl Cy, LA · Accident · No injuries · Closed · Sep 16, 1980 · N27758 · Substantial damage - [NTSB DEN79FA046](https://openairdocs.org/ntsb/DEN79FA046.md): Bell 206B · Gobernador, NM · Accident · No injuries · Closed · Jun 24, 1979 · N16810 · Substantial damage ## The whole list in SQL Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS: ```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_aircrafts.parquet' a JOIN 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c ON c."mKey" = a.case_mkey WHERE a.engine_model_code IN ('03081') ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC ``` This list as a web page: https://openairdocs.org/engine/allison-250-c20b/ntsb --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.