# NTSB investigations: Allison 250-C20 series, WA

NTSB aviation accident and incident investigations since 1962: the probable cause, findings, aircraft, crew, weather and docket of each, linked to the FAA registry and the FAA’s own reports.

## Latest cases

- [NTSB WPR24LA319](https://openairdocs.org/ntsb/WPR24LA319.md): Bell 206L · Fern Prairie, WA · Accident · No injuries · Class 3 · Limited · Final report · Sep 26, 2024 · N9984K · Substantial damage
  > An 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…
- [NTSB WPR18FA074](https://openairdocs.org/ntsb/WPR18FA074.md): Hughes 369D · Pomeroy, WA · Accident · 1 fatal · Field investigation · Final report · Jan 27, 2018 · N369TH · Substantial damage
  > A loss of control following the gunner's failure to ensure that the net maintained clearance from the tail rotor.
- [NTSB GAA17CA369](https://openairdocs.org/ntsb/GAA17CA369.md): Bell 206B · Entiat, WA · Accident · No injuries · Data collection · Final report · Jun 26, 2017 · N183TC · Substantial damage
  > The 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.
- [NTSB WPR16LA188](https://openairdocs.org/ntsb/WPR16LA188.md): Bell 206B · Rockport, WA · Accident · No injuries · Limited investigation · Final report · Sep 12, 2016 · N6181A · Substantial damage
  > The pilot's failure to maintain helicopter control while on the ground, which resulted in mast bumping.
- [NTSB WPR14LA308](https://openairdocs.org/ntsb/WPR14LA308.md): Mdhi 369D · Oso, WA · Accident · Serious injuries · Limited investigation · Final report · Jul 22, 2014 · N5225C · Substantial damage
  > The 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…
- [NTSB WPR13LA287](https://openairdocs.org/ntsb/WPR13LA287.md): Bell 206B · Royal City, WA · Accident · Serious injuries · Limited investigation · Final report · Jun 24, 2013 · N407FK · Substantial damage
  > The pilot's failure to maintain clearance from netting material during a low pass over trees, which resulted in a loss of helicopter control.
- [NTSB WPR09CA338](https://openairdocs.org/ntsb/WPR09CA338.md): Bell 206B · Burlington, WA · Accident · No injuries · Data collection · Final report · Jul 11, 2009 · N302PD · Substantial damage
  > The 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.
- [NTSB SEA07CA256](https://openairdocs.org/ntsb/SEA07CA256.md): Rogerson Hiller RH-1100 · Stanwood, WA · Accident · Minor injuries · Data collection · Final report · Sep 11, 2007 · N6014U · Destroyed
  > The 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.
- [NTSB LAX07LA270](https://openairdocs.org/ntsb/LAX07LA270.md): Hughes 369D · Ellensburg, WA · Accident · 1 fatal · Limited investigation · Final report · Sep 8, 2007 · N31HM · No damage
  > The 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 factor
- [NTSB SEA06TA071](https://openairdocs.org/ntsb/SEA06TA071.md): Bell 206B · Sprague, WA · Accident · No injuries · Final report · Apr 7, 2006 · N96NW · Substantial damage
  > The pilot's failure to maintain clearance from mountainous terrain while maneuvering. Mountainous terrain was a factor.
- [NTSB SEA05MA202](https://openairdocs.org/ntsb/SEA05MA202.md): Agusta A109A II · Edmonds, WA · Accident · 3 fatal · Major investigation · Final report · Sep 30, 2005 · N655GS · Destroyed
  > Loss of control for an undetermined reason during maneuvering flight, which resulted in an in-flight collision with water.
- [NTSB SEA04TA163](https://openairdocs.org/ntsb/SEA04TA163.md): Bell 206B · Mead, WA · Accident · 1 fatal · Final report · Aug 17, 2004 · N34698 · Destroyed
  > The 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…
- [NTSB SEA03LA058](https://openairdocs.org/ntsb/SEA03LA058.md): Hughes 369D · Taholah, WA · Accident · Minor injuries · Limited investigation · Final report · Apr 7, 2003 · N5225C · Substantial damage
  > The 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…
- [NTSB SEA02FA030](https://openairdocs.org/ntsb/SEA02FA030.md): Agusta A109A II · Baring, WA · Accident · Serious injuries · Field investigation · Final report · Jan 20, 2002 · N55NW · Substantial damage
  > The 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…
- [NTSB SEA01LA024](https://openairdocs.org/ntsb/SEA01LA024.md): Bell 206 B3 · Lake Kachess, WA · Accident · No injuries · Limited investigation · Final report · Nov 23, 2000 · N2062D · Substantial damage
  > The 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…
- [NTSB SEA00LA197](https://openairdocs.org/ntsb/SEA00LA197.md): Bell 206BII · Newhalem, WA · Accident · No injuries · Limited investigation · Final report · Aug 24, 2000 · N90307 · Substantial damage
  > Debonding between the elastomeric material and the center plate of the transmission isolation mount.
- [NTSB SEA00FA021](https://openairdocs.org/ntsb/SEA00FA021.md): Bell 206L-3 · Seattle, WA · Accident · Minor injuries · Field investigation · Final report · Nov 17, 1999 · N206AC · 2 aircraft · Substantial damage
  > Adequate separation and lookout not maintained by the pilots of both aircraft.
- [NTSB SEA97LA032](https://openairdocs.org/ntsb/SEA97LA032.md): Hughes 369D · Forks, WA · Accident · Serious injuries · Limited investigation · Final report · Nov 16, 1996 · N5225C · Substantial damage
  > fuel 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.
- [NTSB SEA95LA139](https://openairdocs.org/ntsb/SEA95LA139.md): Hughes 369HS · Orting, WA · Accident · Serious injuries · Limited investigation · Final report · Jul 4, 1995 · N9196F · Substantial damage
  > The pilot's failure to see and avoid the cable.
- [NTSB SEA95LA013](https://openairdocs.org/ntsb/SEA95LA013.md): Hiller UH-12E4 · Morton, WA · Accident · No injuries · Limited investigation · Final report · Oct 28, 1994 · N80NW · Substantial damage
  > A leak in the fuel filler cap and water in the fuel system. A factor to the accident was: inadequate preflight.
- [NTSB SEA94LA094](https://openairdocs.org/ntsb/SEA94LA094.md): Hughes 369D · Rimrock, WA · Accident · Minor injuries · Limited investigation · Final report · Apr 1, 1994 · N5211R · Substantial damage
  > Fuel 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.
- [NTSB SEA91FA184](https://openairdocs.org/ntsb/SEA91FA184.md): Bell 206B · Toutle, WA · Accident · 1 fatal · Field investigation · Final report · Jul 22, 1991 · N276KA · Substantial damage
  > Failure 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.
- [NTSB SEA91FA124](https://openairdocs.org/ntsb/SEA91FA124.md): Bell 206BII · Brewster, WA · Accident · No injuries · Field investigation · Final report · May 28, 1991 · N90307 · Substantial damage
  > The pilot-in-command's selection of unsuitable terrain for the emergency simulation.
- [NTSB SEA85FA104](https://openairdocs.org/ntsb/SEA85FA104.md): Hughes 369D · Spokane, WA · Accident · 2 fatal · Field investigation · Final report · May 5, 1985 · N8365F · Destroyed
  > The 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…
- [NTSB SEA85LA031](https://openairdocs.org/ntsb/SEA85LA031.md): Hiller UH-12ET · Hoquiam, WA · Accident · Minor injuries · Limited investigation · Final report · Dec 18, 1984 · N100LM · Substantial damage
  > Plt 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…
- [NTSB SEA78FYE11](https://openairdocs.org/ntsb/SEA78FYE11.md): Hiller Acft UH-12E · Montesano, WA · Accident · No injuries · Closed · Mar 6, 1978 · N100LM · 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_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
```

This list as a web page: https://openairdocs.org/ntsb?engine=03020&state=WA

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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.