# Final NTSB investigations: Lycoming TVO-435-GIA

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.

Page 1 of 6 · 286 cases

## Latest cases

- [NTSB ERA26LA100](https://openairdocs.org/ntsb/ERA26LA100.md): Bell 47G-3B · Floral City, FL · Accident · No injuries · Class 4 · Limited · Final report · Jan 29, 2026 · N347BH · Destroyed
  > The student pilot’s loss of helicopter control during landing.
- [NTSB ANC24LA065](https://openairdocs.org/ntsb/ANC24LA065.md): Beech 65-B80 · Woleai Atoll, Micronesia · Accident · No injuries · Class 4 · Limited · Final report · Jul 12, 2024 · N44MA · Substantial damage
  > The pilot's selection of an unsuitable takeoff area, resulting in a loss of directional control. Contributing to the accident was a flooded runway.
- [NTSB ERA20LA216](https://openairdocs.org/ntsb/ERA20LA216.md): Bell 47G · Atoka, TN · Accident · No injuries · Class 3 · Limited · Final report · Jun 15, 2020 · N473TT · Substantial damage
  > A total loss of engine power due to a blocked fuel line; the reason for the blockage could not be determined based on the available evidence.
- [NTSB WPR19LA019](https://openairdocs.org/ntsb/WPR19LA019.md): Bell 47G · Wichita Falls, TX · Accident · Serious injuries · Class 3 · Limited · Final report · Nov 2, 2018 · N1159W · Destroyed
  > A total loss of engine power for reasons that could not be determined based on the available information.
- [NTSB CEN18LA306](https://openairdocs.org/ntsb/CEN18LA306.md): Bell 47G 3B · Custer, SD · Accident · Minor injuries · Class 3 · Limited · Final report · Aug 2, 2018 · N347BH · Substantial damage
  > The pilot’s mismanagement of rotor RPM and subsequent forced landing on uneven terrain which led to a dynamic rollover.
- [NTSB CEN18LA269](https://openairdocs.org/ntsb/CEN18LA269.md): Bell 47J · Franklin, IN · Accident · Serious injuries · Limited investigation · Final report · Jul 15, 2018 · N8568F · Destroyed
  > A total loss of engine power for reasons that could not be determined based on the available evidence.
- [NTSB GAA17CA436](https://openairdocs.org/ntsb/GAA17CA436.md): Bell 47G 3B · Toterville, IA · Accident · No injuries · Data collection · Final report · Jul 24, 2017 · N47AH · Substantial damage
  > The pilot’s failure to maintain rotor rpm while maneuvering at low altitude with low airspeed and a tailwind.
- [NTSB WPR16LA069](https://openairdocs.org/ntsb/WPR16LA069.md): Bell 47G 3B 1 · Carson City, NV · Accident · Minor injuries · Limited investigation · Final report · Feb 13, 2016 · N1181W · Substantial damage
  > The pilot's failure to maintain sufficient main rotor rpm, which resulted in a loss of helicopter control and a dynamic rollover.
- [NTSB GAA16CA055](https://openairdocs.org/ntsb/GAA16CA055.md): Bell 47G · Searchlight, NV · Accident · No injuries · Data collection · Final report · Oct 18, 2015 · N73224 · Substantial damage
  > The pilot's failure to maintain adequate clearance from a tree during hover flight.
- [NTSB CEN14LA174](https://openairdocs.org/ntsb/CEN14LA174.md): Bell 47G 3B · Oglesby, TX · Accident · No injuries · Limited investigation · Final report · Mar 30, 2014 · N147WT · Substantial damage
  > Maintenance personnel’s failure to safety wire the throttle control adapter per maintenance instructions when the carburetor was replaced and to detect that the adapter was not safety wired during the annual inspection, which resulted in the throttle control…
- [NTSB CEN13LA395](https://openairdocs.org/ntsb/CEN13LA395.md): Bell 47G-3B-1 · Plover, WI · Accident · Minor injuries · Limited investigation · Final report · Jul 6, 2013 · N7924S · Substantial damage
  > The pilot’s failure to maintain proper engine rpm, which resulted in a high rate of descent and ground impact.
- [NTSB CEN13FA357](https://openairdocs.org/ntsb/CEN13FA357.md): Bell 47G-3B-1 · Maplewood, MN · Accident · 1 fatal · Field investigation · Final report · Jun 19, 2013 · N5024N · Destroyed
  > The loss of helicopter control for reasons that could not be determined because an examination of the helicopter and its systems revealed no malfunctions or failures that would have precluded normal operation.
- [NTSB CEN12CA435](https://openairdocs.org/ntsb/CEN12CA435.md): Bell 47G-3B-2 · Treynor, IA · Accident · No injuries · Data collection · Final report · Jul 9, 2012 · N2919W · Substantial damage
  > The pilot’s improper fuel management, which resulted in a loss of engine power due to fuel exhaustion.
- [NTSB CHI08CA254](https://openairdocs.org/ntsb/CHI08CA254.md): Bell 47G-3B · Kenyon, MN · Accident · No injuries · Data collection · Final report · Aug 14, 2008 · N47AH · Substantial damage
  > The pilot's inadequate preflight planning which resulted in the helicopter settling with power.
- [NTSB CHI08CA210](https://openairdocs.org/ntsb/CHI08CA210.md): Bell 47G-3B-2 · Lafetyette, IN · Accident · No injuries · Data collection · Final report · Jul 24, 2008 · N4029G · Substantial damage
  > The loss of engine power during an aerial application flight due to a fatigue fracture of the carburetor heat control valve spring and the inadequate maintenance inspection by the pilot/mechanic. An additional cause was the low altitude of the operation.
- [NTSB LAX08CA229](https://openairdocs.org/ntsb/LAX08CA229.md): Bell 47G-3B-1 · Shafter, CA · Accident · No injuries · Data collection · Final report · Jul 15, 2008 · N1390X · Substantial damage
  > The pilot's failure to maintain adequate altitude while maneuvering. Contributing factors were the failure of the helicopter's lights during the night flight and the effect of that failure on the pilot's visual perception.
- [NTSB CHI08CA192](https://openairdocs.org/ntsb/CHI08CA192.md): Bell 47G-3B · Port Edwards, WI · Accident · Minor injuries · Data collection · Final report · Jul 11, 2008 · N73995 · Substantial damage
  > The pilot failed to maintain control of the helicopter when he inadvertently flared the helicopter and the rotor rpm decayed as a result of sustaining bee stings during an aerial application flight. Contributing to the accidnet included the bees and the low…
- [NTSB LAX08LA097](https://openairdocs.org/ntsb/LAX08LA097.md): Bell 47G-3B-1 · Denio, NV · Accident · No injuries · Limited investigation · Final report · Apr 11, 2008 · N24SD · Substantial damage
  > The pilot's inadvertent hard landing induced by a perceived loss of power and a main transmission anomaly while maneuvering at low altitude.
- [NTSB DEN07LA155](https://openairdocs.org/ntsb/DEN07LA155.md): Bell 47G-3B-1 · Avondale, CO · Accident · No injuries · Limited investigation · Final report · Sep 12, 2007 · N360SS · Substantial damage
  > The pilot's failure to attain translational lift and his improper flare. A contributing factor in this accident was the sudden wind shift.
- [NTSB DFW06CA055](https://openairdocs.org/ntsb/DFW06CA055.md): Bell 47-B3 · Dennison, TX · Accident · No injuries · Data collection · Final report · Jan 13, 2006 · N1575 · Substantial damage
  > The in-flight separation of the stabilizer bar tube.
- [NTSB DEN05LA137](https://openairdocs.org/ntsb/DEN05LA137.md): Bell 47G-3B-1 · Rock Springs, WY · Accident · No injuries · Limited investigation · Final report · Sep 13, 2005 · N24SD · Substantial damage
  > the pilot's failure to maintain control of the helicopter during the attempted autorotation after he experienced an engine overspeed that occurred for reasons undetermined.
- [NTSB DFW05CA231](https://openairdocs.org/ntsb/DFW05CA231.md): Bell 47 · Monette, AR · Accident · No injuries · Data collection · Final report · Aug 16, 2005 · N8494E · Destroyed
  > The loss of control as result of a loss of hydraulic pressure for undetermined reasons.
- [NTSB SEA05CA122](https://openairdocs.org/ntsb/SEA05CA122.md): Bell 47G-3B-1 · Brewster, WA · Accident · Minor injuries · Data collection · Final report · Jun 19, 2005 · N8554F · Substantial damage
  > The pilot's inadvertent anti-torque pedal input, which resulted in a loss of control and collision with trees while hovering.
- [NTSB SEA04LA114](https://openairdocs.org/ntsb/SEA04LA114.md): Bell 47G-3B-1 · Medford, OR · Accident · Serious injuries · Limited investigation · Final report · Jun 23, 2004 · N73909 · Substantial damage
  > The pilot's failure to maintain clearance from a tree while maneuvering. Trees were a factor.
- [NTSB LAX04CA121](https://openairdocs.org/ntsb/LAX04CA121.md): Bell 47-G3B2 · Salome, AZ · Accident · No injuries · Data collection · Final report · Feb 11, 2004 · N8AG · Substantial damage
  > the pilot's failure to maintain an adequate clearance from trees while approaching the landing zone.
- [NTSB SEA03LA189](https://openairdocs.org/ntsb/SEA03LA189.md): Bell 47G-3B-1 · Diamond, OR · Accident · Serious injuries · Limited investigation · Final report · Sep 12, 2003 · N48020 · Substantial damage
  > Loss of engine power for undetermined reasons during hover.
- [NTSB IAD03LA042](https://openairdocs.org/ntsb/IAD03LA042.md): Bell BHT-47-G3B2A · Lexington, KY · Accident · No injuries · Limited investigation · Final report · Mar 27, 2003 · N47SN · Substantial damage
  > The pilot's failure to maintain directional control while maneuvering to land after a loss of engine power. A factor was the loss of engine power.
- [NTSB SEA03LA023](https://openairdocs.org/ntsb/SEA03LA023.md): Bell 47G · Idaho Falls, ID · Accident · No injuries · Limited investigation · Final report · Jan 2, 2003 · N4759R · Substantial damage
  > In-flight loss of engine power for undetermined reasons.
- [NTSB LAX03TA043](https://openairdocs.org/ntsb/LAX03TA043.md): Bell 47G-3B-1 · Panaca, NV · Accident · No injuries · Final report · Dec 1, 2002 · N48020 · Substantial damage
  > separation of the no. 6 cylinder intake valve head from the valve stem, which resulted in a loss of engine power. The mechanism responsible for the valve failure is unknown.
- [NTSB FTW01LA087](https://openairdocs.org/ntsb/FTW01LA087.md): Bell 47G2 · Ardmore, OK · Accident · No injuries · Limited investigation · Final report · Mar 22, 2001 · N1575 · Substantial damage
  > the loss of tail rotor control during maneuvering resultant from the failure of the tail rotor drive shaft coupling due to a stripped thread which allowed the grease lubricating the shaft to leak out. A factor was the lack of suitable terrain for the forced…
- [NTSB ATL00LA086](https://openairdocs.org/ntsb/ATL00LA086.md): Bell 47G-3B-2 · Pine Hill, AL · Accident · No injuries · Limited investigation · Final report · Sep 9, 2000 · N2243W · Substantial damage
  > The pilot's failure to adequately preflight the helicopter, which resulted in his failure to remove the tie down.
- [NTSB SEA00LA124](https://openairdocs.org/ntsb/SEA00LA124.md): Bell 47G · Haines, OR · Accident · Minor injuries · Limited investigation · Final report · Jul 4, 2000 · N30DP · Substantial damage
  > The pilot's failure to correctly judge his rate of descent and his failure to initiate his level off soon enough to keep the helicopter from impacting the terrain. Factors include hilly terrain near the edge of the field he was spraying.
- [NTSB SEA00FA061](https://openairdocs.org/ntsb/SEA00FA061.md): Bell 47G-3B-1 · Stanwood, WA · Accident · 1 fatal · Field investigation · Final report · Apr 2, 2000 · N3377H · Destroyed
  > The disengagement of the oil jet fitting from its threaded receptacle at the forward end of the engine crankshaft. This resulted in excessive oil within the clutch assembly, the subsequent slipping of the clutch, and ultimately the disengagement of the rotor…
- [NTSB DEN99LA168](https://openairdocs.org/ntsb/DEN99LA168.md): Bell 47G3B2A · Tremonton, UT · Accident · No injuries · Limited investigation · Final report · Sep 23, 1999 · N83246 · Substantial damage
  > The pilot's failure to maintain rotor rpm while attempting a precautionary autorotation landing. A factor was the loss of engine power for undetermined reasons.
- [NTSB MIA99LA217](https://openairdocs.org/ntsb/MIA99LA217.md): Bell 47G-B3 · Selma, AL · Accident · No injuries · Limited investigation · Final report · Aug 8, 1999 · N6712D · Substantial damage
  > The pilot's failure to maintain the proper touchdown point during landing causing the landing skid to become entangled with the edge of the helipad platform and the resultant rollover and main rotor blade strike of the tow vehicle.
- [NTSB ATL99LA105](https://openairdocs.org/ntsb/ATL99LA105.md): Bell 47 · Trenton, GA · Accident · Minor injuries · Limited investigation · Final report · Jul 2, 1999 · N23590 · Substantial damage
  > The loss of main rotor rpm due to improper use of the flight controls by the pilot. Factors were the tailwind and trees.
- [NTSB SEA99LA098](https://openairdocs.org/ntsb/SEA99LA098.md): Bell 47G3B2A · Pendleton, OR · Accident · No injuries · Limited investigation · Final report · Jun 10, 1999 · N24MP · Substantial damage
  > A fouled external load cable, and the pilot's operation of the helicopter with a non-approved external bucket installation, resulting in misrouted hydraulic lines and consequent malfunction of the external load release system.
- [NTSB FTW98LA400](https://openairdocs.org/ntsb/FTW98LA400.md): Bell 47-G-2 · Ardmore, OK · Accident · No injuries · Limited investigation · Final report · Sep 17, 1998 · N1575 · Substantial damage
  > The pilots failure to maintain clearance with terrain and the ensuing loss of control.
- [NTSB CHI98LA198](https://openairdocs.org/ntsb/CHI98LA198.md): Bell 47G · Le Center, MN · Accident · Serious injuries · Limited investigation · Final report · Jun 10, 1998 · N73284 · Destroyed
  > the pilot's failure to maintain clearance with the wire. A factor associated with the accident was the wire which the helicopter contacted.
- [NTSB SEA98LA069](https://openairdocs.org/ntsb/SEA98LA069.md): Bell 47G3B2A · Stanwood, WA · Accident · No injuries · Limited investigation · Final report · May 3, 1998 · N7965J · Substantial damage
  > The failure of the number two connecting rod, which led to additional internal engine damage and a complete loss of power. Factors include soft terrain in the area where the pilot found it necessary to execute his forced landing.
- [NTSB FTW98GA097](https://openairdocs.org/ntsb/FTW98GA097.md): Bell 47G-3B-2 · Spanish Fork, UT · Accident · 1 fatal · Final report · Jan 14, 1998 · N1461W · Substantial damage
  > A total loss of power due to repeated engine overspeeds. A related factor was unsuitable terrain.
- [NTSB SEA98LA006](https://openairdocs.org/ntsb/SEA98LA006.md): Bell 47-G3B · Winston, MT · Accident · No injuries · Limited investigation · Final report · Oct 19, 1997 · N47AH · Substantial damage
  > Fuel starvation due to fuel flow restriction from a failed carburetor automatic mixture control device. Factors include night light conditions for the forced landing.
- [NTSB FTW97LA319](https://openairdocs.org/ntsb/FTW97LA319.md): Bell 47G-3B-2 · Montrose, CO · Accident · No injuries · Limited investigation · Final report · Aug 19, 1997 · N2243W · Substantial damage
  > failure of the flight instructor (CFI) to properly supervise the flight and ensure that adequate rotor rpm was maintainted during the autorotation/landing. The high density altitude was a related factor.
- [NTSB IAD97LA104](https://openairdocs.org/ntsb/IAD97LA104.md): Bell 47G-3B-1 · Mt. Vernon, OH · Accident · Minor injuries · Limited investigation · Final report · Jul 26, 1997 · N35134 · Substantial damage
  > The pilot's failure to maintain rotor RPM.
- [NTSB SEA97LA168](https://openairdocs.org/ntsb/SEA97LA168.md): Bell 47G-3B · Idaho Falls, ID · Accident · Minor injuries · Limited investigation · Final report · Jul 14, 1997 · N8494E · Substantial damage
  > The pilot mismanaged his fuel supply which led to fuel exhaustion and subsequent loss of engine power. Factors contributing to the accident were the lack of adequate altitude and airspeed to successfully execute an autorotation.
- [NTSB SEA97LA158](https://openairdocs.org/ntsb/SEA97LA158.md): Bell 47G-3B-1 · Roosevelt, UT · Accident · Serious injuries · Limited investigation · Final report · Jul 5, 1997 · N8537F · Substantial damage
  > the pilot's failure to maintain directional control. Wind gusts were a factor.
- [NTSB LAX97TA213](https://openairdocs.org/ntsb/LAX97TA213.md): Bell 47G-3B-1 · Fallon, NV · Accident · No injuries · Final report · Jun 16, 1997 · N1335X · Substantial damage
  > exhaustion of the aircraft's fuel supply, due to improper planning and/or decision. A factor related to the accident was the high density altitude which made a successful autorotative landing unlikely.
- [NTSB SEA97LA112](https://openairdocs.org/ntsb/SEA97LA112.md): Bell 47G-3B · Snohomish, WA · Accident · Minor injuries · Limited investigation · Final report · May 15, 1997 · N8491E · Substantial damage
  > the pilot's encounter with of a loss of tail rotor effectiveness (LTE) situation, and his subsequent inadequate remedial action. Related factors included: wind conditions that were conducive to an unanticipated right yaw event, and the pilot's limited…
- [NTSB MIA96LA235](https://openairdocs.org/ntsb/MIA96LA235.md): Bell 47G-3B-1 · Borinquen, PR · Accident · No injuries · Limited investigation · Final report · Sep 29, 1996 · N1397X · Substantial damage
  > the pilot failed to maintain control of the aircraft while hover taxing. Factors in this accident were wind gusts and a tailwind.
- [NTSB FTW96TA383](https://openairdocs.org/ntsb/FTW96TA383.md): Bell 47G-3B-1 · Rangely, CO · Accident · No injuries · Final report · Sep 10, 1996 · N1335X · Substantial damage
  > the pilot's excessive cyclic control input during a low altitude operation, and his failure to maintain altitude/clearance from high vegetation (sage brush). The proximity of high vegetation was a related factor.

Next page: https://openairdocs.org/ntsb.md?engine=41526&status=final&page=2

## 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."completionStatus" = 'Completed'
  AND c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41526'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=41526&status=final

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