# NTSB investigations: Lycoming VO-435 series

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 4 of 13 · 629 cases

## Cases, newest first

- [NTSB FTW92LA159](https://openairdocs.org/ntsb/FTW92LA159.md): Bell 47G-2 · Danbury, TX · Accident · No injuries · Limited investigation · Final report · Jun 14, 1992 · N6746D · Substantial damage
  > The failure of the landing gear skid due to internal corrosion. A factor was the soft ground.
- [NTSB BFO92LA062](https://openairdocs.org/ntsb/BFO92LA062.md): Continental Copters MK6B · Middleboro, MA · Accident · No injuries · Limited investigation · Final report · May 14, 1992 · N9012T · Substantial damage
  > The pilot's failure to release a tie down strap from the helicopter's skid during the preflight.
- [NTSB CHI92LA137](https://openairdocs.org/ntsb/CHI92LA137.md): Bell 47-G2A · Dousman, WI · Accident · Serious injuries · Limited investigation · Final report · Apr 30, 1992 · N52HB · Substantial damage
  > The in-flight loss of the swash plate drive link bolt which allowed the swash plate drive assembly to disconnect.
- [NTSB FTW92LA044](https://openairdocs.org/ntsb/FTW92LA044.md): Hiller-Osborn UH-12D · Rio Medina, TX · Accident · No injuries · Limited investigation · Final report · Dec 2, 1991 · N67065 · Substantial damage
  > The pilot's improper flare during touchdown.
- [NTSB MIA92WA037](https://openairdocs.org/ntsb/MIA92WA037.md): Bell-Transworld 47G2 · David, Panama · Accident · No injuries · Foreign investigation · Nov 25, 1991 · N64589 · Substantial damage
- [NTSB FTW91LA166](https://openairdocs.org/ntsb/FTW91LA166.md): Bell 47G-5A · Pearsall, TX · Accident · Minor injuries · Limited investigation · Final report · Sep 26, 1991 · N59424 · Destroyed
  > The pilot's failure to maintain adequate visual lookout for obstacles during operations from a remote site.
- [NTSB CHI91FA294](https://openairdocs.org/ntsb/CHI91FA294.md): Bell-K Copter 47D1 · Laurie, MO · Accident · 3 fatal · Field investigation · Final report · Sep 15, 1991 · N7768 · Destroyed
  > Poor judgement of the pilot, due to impairment from consumption of alcoholic beverage before flight, his intentional buzzing, and his inadequate visual lookout (failure to see-and-avoid power lines).
- [NTSB MIA91LA215](https://openairdocs.org/ntsb/MIA91LA215.md): Bell 47G2A · Immokalee, FL · Accident · No injuries · Limited investigation · Final report · Sep 7, 1991 · N7573 · Substantial damage
  > The improper use of the flight controls by the pilot in command, which resulted in a collision with the ground and a nose over.
- [NTSB LAX91LA369](https://openairdocs.org/ntsb/LAX91LA369.md): Hiller UH12D · Sparks, NV · Accident · No injuries · Limited investigation · Final report · Aug 25, 1991 · N100HH · Substantial damage
  > The encounter with rough, unsuitable terrain during a precautionary landing. Contributing to the accident was the pilot's decision to make an autorotation after encountering an airframe vibration.
- [NTSB CHI91LA245](https://openairdocs.org/ntsb/CHI91LA245.md): Hiller 1345 · Michigan City, IN · Accident · Serious injuries · Limited investigation · Final report · Aug 3, 1991 · N57972 · Substantial damage
  > Fuel exhaustion due the pilot's delay in refueling. Factors related to the accident were pressure induced by others (passenger), and the absence of suitable terrain.
- [NTSB FTW91LA125](https://openairdocs.org/ntsb/FTW91LA125.md): Bell 47G-2 · Slidell, LA · Accident · No injuries · Limited investigation · Final report · Jul 22, 1991 · N312SH · Substantial damage
  > The pilot performing a touchdown autorotation to unsuitable terrain. Factors were the soft terrain and the inadequate supervision by the FAA inspector.
- [NTSB CHI91LA205](https://openairdocs.org/ntsb/CHI91LA205.md): Hiller UH-12D · Savoy, IL · Accident · No injuries · Limited investigation · Final report · Jul 2, 1991 · N94515 · Substantial damage
  > The pilot's failure to maintain tail rotor clearance from the ground. A related factor is the pilot's lack of total experience in helicopters.
- [NTSB FTW91LA091](https://openairdocs.org/ntsb/FTW91LA091.md): Bell 47D-1 · Peach Orchard, AR · Accident · No injuries · Limited investigation · Final report · Jun 5, 1991 · N8117 · Substantial damage
  > The pilot's failure to maintain adequate main rotor RPM resulting in deteriorated helicopter performance. A factor was the tailwind condition.
- [NTSB SEA91LA077](https://openairdocs.org/ntsb/SEA91LA077.md): Bell BH-47G2A · Waitsburg, WA · Accident · No injuries · Limited investigation · Final report · Mar 31, 1991 · N38926 · Substantial damage
  > The improper installation of the main rotor mast nut and lock washer by maintenance personnel which resulted in the separation of the main rotor system.
- [NTSB MIA91TL#03](https://openairdocs.org/ntsb/MIA91TL%2303.md): Bell 47-G5A · Titusville, FL · Accident · No injuries · Class 3 · Final report · Mar 27, 1991 · N7925J · Substantial damage
- [NTSB LAX91LA128](https://openairdocs.org/ntsb/LAX91LA128.md): Bell 47G-5A · Farmington, CA · Accident · No injuries · Limited investigation · Final report · Mar 10, 1991 · N59403 · Substantial damage
  > The contamination of the engine induction air filter. Soft terrain during the touchdown was a factor in the accident.
- [NTSB LAX91LA013](https://openairdocs.org/ntsb/LAX91LA013.md): Bell 47G5 · Antarctica · Accident · 2 fatal · Limited investigation · Final report · Oct 22, 1990 · N2294W · Destroyed
  > The pilot's failure to maintain on adequate altitude while maneuvering above the water.
- [NTSB CHI90LA205](https://openairdocs.org/ntsb/CHI90LA205.md): Bell 47G-5 · Hudson, IA · Accident · No injuries · Limited investigation · Final report · Jul 30, 1990 · N8140J · Substantial damage
  > Improper touchdown performed by the pilot in command.
- [NTSB MKC90LA144](https://openairdocs.org/ntsb/MKC90LA144.md): Bell 47D-1 · Fair Oaks, AR · Accident · Minor injuries · Limited investigation · Final report · Jul 12, 1990 · N8117 · Substantial damage
  > Tail rotor cable disengagement due to inadequate maintenance.
- [NTSB CHI90DEP07](https://openairdocs.org/ntsb/CHI90DEP07.md): Bell 47-G2 · Hatley, WI · Accident · No injuries · Final report · Jul 10, 1990 · N6768D · Substantial damage
  > The partial loss of power due to sticking intake valves.
- [NTSB MKC90LA138](https://openairdocs.org/ntsb/MKC90LA138.md): Hiller 12-E · Watson, MN · Accident · No injuries · Limited investigation · Final report · Jun 26, 1990 · N62397 · Substantial damage
  > Pilot misjudged his flare and collided with the terrain.
- [NTSB NYC90LA122](https://openairdocs.org/ntsb/NYC90LA122.md): Bell 47G-3B1 · Becket, MA · Accident · No injuries · Limited investigation · Final report · May 31, 1990 · N39268 · Substantial damage
  > A power loss due to oil starvation, after maintenance personnel failed to comply with Lycoming directives during the engine overhaul. Factors related to the accident were: improper adjustment of the engine oil pressure by maintenance personnel and unsuitable…
- [NTSB LAX90LA042](https://openairdocs.org/ntsb/LAX90LA042.md): Bell 47G-II · Rialto, CA · Accident · Minor injuries · Limited investigation · Final report · Dec 2, 1989 · N2899B · Destroyed
  > The pilot's loss of directional control and subsequent overcontrol while hovering. Contributing to the accident were the gusty wind conditions and the pilot's inexperience.
- [NTSB LAX90DVM01](https://openairdocs.org/ntsb/LAX90DVM01.md): Bell 47G-5 · Guadalupe, CA · Accident · No injuries · Final report · Nov 1, 1989 · N4798R · Substantial damage
  > The pilot's failure to maintain sufficient clearance allowing the aircraft to collide with a wooden power pole. Contributing to the accident was the sunglare which inhibited the pilot's vision.
- [NTSB ATL90DKJ02](https://openairdocs.org/ntsb/ATL90DKJ02.md): Bell 47G2 · Wettumpka, AL · Accident · No injuries · Final report · Oct 27, 1989 · N9025 · Destroyed
  > The pilot's failure to avoid obstacles during aerial application maneuvering.
- [NTSB MIA89LA240](https://openairdocs.org/ntsb/MIA89LA240.md): Bell 47G-2 · Cayey, PR · Accident · No injuries · Limited investigation · Final report · Sep 3, 1989 · N37870 · Substantial damage
  > Loss of engine power for an unknown reason. A factor related to the accident was: the presence of trees in the emergency landing area.
- [NTSB MIA89LA221](https://openairdocs.org/ntsb/MIA89LA221.md): Continental Copters Tomcat MK6C · Quitman, MS · Accident · Serious injuries · Limited investigation · Final report · Aug 14, 1989 · N9085T · Destroyed
  > Failure of the tail boom attachment.
- [NTSB MIA89LA213](https://openairdocs.org/ntsb/MIA89LA213.md): Bell 47G-2 · Sarasota, FL · Accident · No injuries · Limited investigation · Final report · Aug 5, 1989 · N3550 · Substantial damage
  > The student pilot's inadequate preflight planning/preparation, which resulted in fuel exhaustion due to an inadequate supply of fuel. Factors related to the accident were: the student pilot's lack of total experience & tree(s) in the emergency landing area.
- [NTSB ATL89FA193](https://openairdocs.org/ntsb/ATL89FA193.md): Texas Helicopter OH-13/M74 · Norman Park, GA · Accident · 1 fatal · Field investigation · Final report · Aug 2, 1989 · N51850 · Destroyed
  > Improper planning/decision by the pilot, which resulted in his physical impairment from exposure to lannate, and his failure to maintain altitude/clearance above the ground. A factor related to the accident was: failure of the pilot to use a respirator while…
- [NTSB LAX89DVA07](https://openairdocs.org/ntsb/LAX89DVA07.md): Texas Helicopter OH-13E/M74 · Hilmar, CA · Accident · No injuries · Final report · Jul 16, 1989 · N38117 · Destroyed
  > The pilot's loss of directional control during an attempted takeoff from a loading platform.
- [NTSB CHI89DEX05](https://openairdocs.org/ntsb/CHI89DEX05.md): Texas Helicopter OH-13H/M74A · New Richmond, IN · Accident · No injuries · Final report · Jul 13, 1989 · N10002 · Substantial damage
  > The pilot's misjudgement of the fuel supply which resulted in fuel exhaustion.
- [NTSB BFO89LA049](https://openairdocs.org/ntsb/BFO89LA049.md): Bell 47J · Fruitland, MD · Accident · No injuries · Limited investigation · Final report · Jul 2, 1989 · N6760D · Substantial damage
  > Poor judgement of the pilot by flying, while physically impaired by alcohol, and his misjudgement of clearance between the helicopter and the structure. The dark night and object (structure) were considered to be contributing factors.
- [NTSB SEA89LA098](https://openairdocs.org/ntsb/SEA89LA098.md): Bell 47G-2 · Buena, WA · Accident · Serious injuries · Limited investigation · Final report · Jun 2, 1989 · N41721 · Destroyed
  > The pilot's failure to maintain an adequate visual lookout and clearance to avoid the power lines.
- [NTSB LAX88DUG07](https://openairdocs.org/ntsb/LAX88DUG07.md): Bell 47G-5A · Perris, CA · Accident · No injuries · Final report · Sep 18, 1988 · N4099G · Substantial damage
  > On liftoff, tail rotor control was lost and helicopter spun with main rotor striking terrain. Investigation revealed fatigue failure of engine mounting cage. The eng basket had failed and allowed the t/r drive shaft to pull out of the coupling. The basket had…
- [NTSB LAX88DUQ04](https://openairdocs.org/ntsb/LAX88DUQ04.md): Texas Helicopter M74A · Lancaster, CA · Accident · No injuries · Final report · Aug 19, 1988 · N51862 · Substantial damage
  > During an aerial application flight, just after takeoff, the nose of the helicopter suddenly pitched up. The pilot reduced power to keep from climbing. The fore/aft cyclic control had no effect. The helicopter settled to the ground resulting in substantial…
- [NTSB NYC88LA214](https://openairdocs.org/ntsb/NYC88LA214.md): Bell 47G5 · Biddeford, ME · Accident · Minor injuries · Limited investigation · Final report · Aug 11, 1988 · N14861 · Substantial damage
  > The helicopter made an approach to a low hover above a hard surfaced rwy. The helicopter was slowly air taxiing when the plt felt the helicopter become unstable directionally and he considered making a run-on landing. However, before he could make the landing…
- [NTSB MIA88LA250](https://openairdocs.org/ntsb/MIA88LA250.md): Continental Copters MK-5A · Valley Park, MS · Accident · Minor injuries · Limited investigation · Final report · Aug 10, 1988 · N9086T · Substantial damage
  > The pilot stated that he thought he had 8 gallons of fuel prior to takeoff. The engine failed about 100 ft AGL and he attempted to stretch the glide of the helicopter by using collective pitch. The aircraft hit hard and rolled over. Only 1 quart of fuel was…
- [NTSB CHI88DEX11](https://openairdocs.org/ntsb/CHI88DEX11.md): Continental Copters MK-5 · Redkey, IN · Accident · 1 fatal · Final report · Aug 10, 1988 · N25561 · Destroyed
  > Physical impairment of the pilot due to drugs which resulted in a misjudged approach and subsequent contact with trees during the approach to an aerial application swath run.
- [NTSB CHI88DET05](https://openairdocs.org/ntsb/CHI88DET05.md): Bell 47J · Dowagiac, MI · Accident · No injuries · Final report · Aug 5, 1988 · N2838B · Substantial damage
  > Failure to maintian adequate rotor RPM by the unqualified pilot.
- [NTSB CHI88DEX08](https://openairdocs.org/ntsb/CHI88DEX08.md): Continental Copters Tomcat MK-6 · Straughn, IN · Accident · No injuries · Final report · Jul 11, 1988 · N9093T · Substantial damage
  > Aerial application helicopter struck power lines in field on first swath run. This was the first time the pilot had sprayed this field. Prior to spraying the field he questioned the farmer regarding power lines or other obstructions. The farmer replied that…
- [NTSB MIA88LA186](https://openairdocs.org/ntsb/MIA88LA186.md): Continental Copters MK6B · Callahan, FL · Accident · No injuries · Limited investigation · Final report · Jun 1, 1988 · N9080T · Substantial damage
  > While maneuvering the helicopter during an aerial application flt the eng quit. During the autorotative landing the helicopter landed hard. Examination of the eng revealed the accessory drive gear, which is attached to the crankshaft by 6 AN-4A bolts with the…
- [NTSB CHI88DEM05](https://openairdocs.org/ntsb/CHI88DEM05.md): Bell 47G-2A · Midland, MI · Accident · No injuries · Final report · May 31, 1988 · N440TG · Substantial damage
  > The plt rprtd that before takeoff, he checked the fuel gage & concluded there was enough fuel to dispense his load. However, after spraying out the load, he started to return to the landing site & then the eng lost power from fuel exhaustion. The helicopter…
- [NTSB MKC88LA092](https://openairdocs.org/ntsb/MKC88LA092.md): Bell 47G-2 · Mc Dougal, AR · Accident · No injuries · Limited investigation · Final report · May 19, 1988 · N4690 · Substantial damage
  > The pilot stated that he had just begun the spraying of a rice field when one of the spray nozzles malfunctioned. As he was attempting to set the helicopter down on the ground, to work on the nozzle, the main rotor blades struck a tree. The main rotor blades…
- [NTSB LAX88LA126](https://openairdocs.org/ntsb/LAX88LA126.md): Bell 47G-2A-1 · Oceanside, CA · Accident · Minor injuries · Limited investigation · Final report · Mar 11, 1988 · N73969 · Destroyed
  > The non-U.S. Certificated pilot lost control of the helicopter while hovering 3-FT AGL during a maintenance test flight. The acft descended, touched down hard and rolled over. The non-english speaking pilot immediately departed the scene & reportedly headed…
- [NTSB FTW88DRA03](https://openairdocs.org/ntsb/FTW88DRA03.md): Hiller UH-12-D · Bon-Wier, TX · Accident · Serious injuries · Final report · Feb 17, 1988 · N48265 · Destroyed
  > Ground crewmember's failure to follow established procedures for secureing the aircraft to the transport trailer.
- [NTSB SEA88LA014](https://openairdocs.org/ntsb/SEA88LA014.md): Bell 47G2 · Lebanon, OR · Accident · No injuries · Limited investigation · Final report · Oct 26, 1987 · N6141 · Substantial damage
  > The student was performing an autorotation at about 50' AGL and the flare was begun. The instructor pilot noticed that the helicopter was not leveling and took control of the aircraft. The helicopter settled tail low onto the soft ground striking the tail…
- [NTSB FTW88LA008](https://openairdocs.org/ntsb/FTW88LA008.md): Bell 47G-2 · Lapra, TX · Accident · No injuries · Limited investigation · Final report · Oct 20, 1987 · N8403E · Substantial damage
  > Upon entering a bank approx. 80 to 100 ft. off the ground, the aircraft experienced a power loss with vibration. During autorotation the aircraft contacted a tree causing substantial damage. Examination of the wreckage found the transmission clutch assembly…
- [NTSB FTW87DPJ09](https://openairdocs.org/ntsb/FTW87DPJ09.md): G&C Helicopters EL Tomcat MK5A · Marlow, OK · Accident · Serious injuries · Final report · Sep 23, 1987 · N17315 · Substantial damage
  > Pilot failed to see and avoid tree at end of swath run during a spraying operation. After contacting the tree, the helicopter started to spin and struck the ground in an approximate 90 degree right bank and started to burn.
- [NTSB ATL87LA249](https://openairdocs.org/ntsb/ATL87LA249.md): Bell 47G3B1 · Enterprise, AL · Accident · No injuries · Limited investigation · Final report · Sep 6, 1987 · N38CD · Substantial damage
  > During a practice autorotation, the instructor pilot delayed in appling power to arrest the autorotative descent. The other pilot reported that the autorotation profile was was not the same as the previous successful autorotation. There were no reported…
- [NTSB MIA87FA236](https://openairdocs.org/ntsb/MIA87FA236.md): Cessna 152 · Opa Locka, FL · Accident · 1 fatal · Field investigation · Final report · Aug 31, 1987 · N48864 · 2 aircraft · Substantial damage
  > A student plt & instructor (CFI) in Cessna 152, N48864, took off & entered rgt traffic to practice lndgs on rwy 9R. Soonthereafter, a helicopter plt (h/p) in a bell 47G-2, N6728D, took off & entered rgt traffic to practice lndgs in a desig-nated helicopter…

Next page: https://openairdocs.org/ntsb.md?engine=41525&page=5

## 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."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41525'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=41525&page=4

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