NTSB investigations: Allison 250-C20 series, WA

26 cases on aircraft whose registry engine model is Allison 250-C20 series. 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

19782026
NTSB investigations: Allison 250-C20 series, WA per year, 1978–2026: 26 cases
19781
19841
19851
19912
19942
19951
19961
19991
20002
20021
20031
20041
20051
20061
20072
20091
20131
20141
20161
20171
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.\"eventStateOrRegion\" = 'WA' AND c.\"eventCountry\" = 'USA'
    AND c.\"mKey\" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('03020'))
  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 WPR24LA319Accident · No injuriesClass 3 · LimitedFinal reportBell 206L · Fern Prairie, WAAn aeroelastic interaction between the helicopter’s main rotor blades and nodal beam system, which resulted in oscillations that exceeded the design limits of the tailboom. Contributing to the accident was the failure of the main rotor blade manufacturer to…Sep 26, 2024 · N9984K · Substantial damageNTSB WPR18FA074Accident · 1 fatalField investigationFinal reportHughes 369D · Pomeroy, WAA loss of control following the gunner's failure to ensure that the net maintained clearance from the tail rotor.Jan 27, 2018 · N369TH · Substantial damageNTSB GAA17CA369Accident · No injuriesData collectionFinal reportBell 206B · Entiat, WAThe pilot’s failure to secure a loose item inside the cockpit that interfered with antitorque pedal control and led to a loss of helicopter control due to a loss of tail rotor effectiveness.Jun 26, 2017 · N183TC · Substantial damageNTSB WPR16LA188Accident · No injuriesLimited investigationFinal reportBell 206B · Rockport, WAThe pilot's failure to maintain helicopter control while on the ground, which resulted in mast bumping.Sep 12, 2016 · N6181A · Substantial damageNTSB WPR14LA308Accident · Serious injuriesLimited investigationFinal reportMdhi 369D · Oso, WAThe pilot/mechanic’s failure to properly perform required inspections of the main rotor blades at the necessary intervals, which resulted in an in-flight separation of a main rotor blade due to disbonding and fatigue cracking. Contributing to the accident was…Jul 22, 2014 · N5225C · Substantial damageNTSB WPR13LA287Accident · Serious injuriesLimited investigationFinal reportBell 206B · Royal City, WAThe pilot's failure to maintain clearance from netting material during a low pass over trees, which resulted in a loss of helicopter control.Jun 24, 2013 · N407FK · Substantial damageNTSB WPR09CA338Accident · No injuriesData collectionFinal reportBell 206B · Burlington, WAThe pilot’s failure to maintain control of the helicopter while attempting to lift off from a trailer. The helicopter subsequently impacted the ground and rolled over.Jul 11, 2009 · N302PD · Substantial damageNTSB SEA07CA256Accident · Minor injuriesData collectionFinal reportRogerson Hiller RH-1100 · Stanwood, WAThe pilot's failure to execute a go-around and his failure to reduce his groundspeed to zero prior to touching down on the rough/uneven terrain. Factors include the momentary restriction of a flight control, rough/uneven terrain, and a tailwind.Sep 11, 2007 · N6014U · DestroyedNTSB LAX07LA270Accident · 1 fatalLimited investigationFinal reportHughes 369D · Ellensburg, WAThe passenger's inadequate visual lookout and failure to maintain clearance from the rotating main rotor disc while the helicopter was hovering. An uphill terrain condition was a factorSep 8, 2007 · N31HM · No damageNTSB SEA06TA071Accident · No injuriesFinal reportBell 206B · Sprague, WAThe pilot's failure to maintain clearance from mountainous terrain while maneuvering. Mountainous terrain was a factor.Apr 7, 2006 · N96NW · Substantial damageNTSB SEA05MA202Accident · 3 fatalMajor investigationFinal reportAgusta A109A II · Edmonds, WALoss of control for an undetermined reason during maneuvering flight, which resulted in an in-flight collision with water.Sep 30, 2005 · N655GS · DestroyedNTSB SEA04TA163Accident · 1 fatalFinal reportBell 206B · Mead, WAThe reversal of the reel machine during a sock line pull which resulted in a loss of control while hovering out of ground effect. Factors were the failure of company management to develop adequate procedures for conducting sock line pulls, the inadequate…Aug 17, 2004 · N34698 · DestroyedNTSB SEA03LA058Accident · Minor injuriesLimited investigationFinal reportHughes 369D · Taholah, WAThe entanglement of the fuel quantity sender float in the start pump wiring within the fuel tank as a result of the wiring not being properly secured. This rendered the fuel gauge inaccurate and the low fuel warning light inoperative which led to fuel…Apr 7, 2003 · N5225C · Substantial damageNTSB SEA02FA030Accident · Serious injuriesField investigationFinal reportAgusta A109A II · Baring, WAThe sequential non-mechanical total loss of power in both engines 1 and 2 for undetermined reasons and the pilot's failure to maintain adequate rotor RPM to prevent a hard landing. Contributing factors were the tripped "RPM WARN" circuit breaker which…Jan 20, 2002 · N55NW · Substantial damageNTSB SEA01LA024Accident · No injuriesLimited investigationFinal reportBell 206 B3 · Lake Kachess, WAThe pilot's failure to comply with the flight manual regarding the use of an induction system deflector kit (snow baffles) while operating in snow, and the ingestion of foreign material/snow that resulted in an engine flameout while hovering. A snow baffle…Nov 23, 2000 · N2062D · Substantial damageNTSB SEA00LA197Accident · No injuriesLimited investigationFinal reportBell 206BII · Newhalem, WADebonding between the elastomeric material and the center plate of the transmission isolation mount.Aug 24, 2000 · N90307 · Substantial damageNTSB SEA00FA021Accident · Minor injuriesField investigationFinal reportBell 206L-3 · Seattle, WAAdequate separation and lookout not maintained by the pilots of both aircraft.Nov 17, 1999 · N206AC · 2 aircraft · Substantial damageNTSB SEA97LA032Accident · Serious injuriesLimited investigationFinal reportHughes 369D · Forks, WAfuel contamination, which resulted in loss of engine power. Factors relating to the accident included: improper servicing of the helicopter, and a lack of suitable terrain for an emergency landing due to the proximity of trees.Nov 16, 1996 · N5225C · Substantial damageNTSB SEA95LA139Accident · Serious injuriesLimited investigationFinal reportHughes 369HS · Orting, WAThe pilot's failure to see and avoid the cable.Jul 4, 1995 · N9196F · Substantial damageNTSB SEA95LA013Accident · No injuriesLimited investigationFinal reportHiller UH-12E4 · Morton, WAA leak in the fuel filler cap and water in the fuel system. A factor to the accident was: inadequate preflight.Oct 28, 1994 · N80NW · Substantial damageNTSB SEA94LA094Accident · Minor injuriesLimited investigationFinal reportHughes 369D · Rimrock, WAFuel exhaustion, the pilot in command's failure to refuel the aircraft, and the inability to successfully execute an auto- rotation landing because of the low altitude.Apr 1, 1994 · N5211R · Substantial damageNTSB SEA91FA184Accident · 1 fatalField investigationFinal reportBell 206B · Toutle, WAFailure of the pilot to maintain airspeed and correct for the right yawing condition. Factors to the accident were: inadequate compensation for wind conditions, diverted attention, and lack of total expereince in type of aircraft.Jul 22, 1991 · N276KA · Substantial damageNTSB SEA91FA124Accident · No injuriesField investigationFinal reportBell 206BII · Brewster, WAThe pilot-in-command's selection of unsuitable terrain for the emergency simulation.May 28, 1991 · N90307 · Substantial damageNTSB SEA85FA104Accident · 2 fatalField investigationFinal reportHughes 369D · Spokane, WAThe helicopter was on a flt to a tv station to transport a tv camera man & his gear. The regular plt for this trip was unable to fly, so another was retained for the flt. This was his 1st flt to the station. Helicopter operations at the tv station were…May 5, 1985 · N8365F · DestroyedNTSB SEA85LA031Accident · Minor injuriesLimited investigationFinal reportHiller UH-12ET · Hoquiam, WAPlt reported that while in normal cruise flight, a total loss of power occurred. Autorotation was effected in mountainous, wooded terrain. Examination of the engine showed continuity and freedom of rotation. Examination of the fuel system disclosed no…Dec 18, 1984 · N100LM · Substantial damageNTSB SEA78FYE11Accident · No injuriesClosedHiller Acft UH-12E · Montesano, WAMar 6, 1978 · N100LM · Substantial damage