# NTSB investigations: Hiller UH-12E, CA

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 2 · 98 cases

## Latest cases

- [NTSB WPR20LA007](https://openairdocs.org/ntsb/WPR20LA007.md): Hiller UH 12E · Susanville, CA · Accident · Minor injuries · Class 3 · Limited · Final report · Oct 14, 2019 · N131HA · Substantial damage
  > A partial loss of engine power due to multiple overtemperature events and a hot start event, which resulted in thermally damaged internal components of the engine. Contributing to the accident was the lack of suitable terrain on which to perform the forced…
- [NTSB WPR15LA168](https://openairdocs.org/ntsb/WPR15LA168.md): Hiller UH 12E · Wasco, CA · Accident · 1 fatal · Limited investigation · Final report · May 27, 2015 · N138HA · Substantial damage
  > An in-flight impact with terrain for reasons that could not be determined based on available evidence.
- [NTSB WPR15LA138](https://openairdocs.org/ntsb/WPR15LA138.md): Hiller UH 12E · Firebaugh, CA · Accident · No injuries · Limited investigation · Final report · Mar 29, 2015 · N130HA · Substantial damage
  > A loss of engine power for reasons that could not be determined because postaccident examination of the engine did not reveal any anomalies that would have precluded normal operation.
- [NTSB WPR14LA062](https://openairdocs.org/ntsb/WPR14LA062.md): Hiller UH 12E · Chowchilla, CA · Accident · No injuries · Limited investigation · Final report · Dec 9, 2013 · N36MV · Substantial damage
  > The failure of the torsional drive coupling, which resulted in a loss of drive to the main rotor system during low-altitude flight.
- [NTSB WPR11LA267](https://openairdocs.org/ntsb/WPR11LA267.md): Hiller UH-12E · Lost Hills, CA · Accident · Minor injuries · Limited investigation · Final report · Jun 19, 2011 · N138HA · Substantial damage
  > The failure of the engine-driven fuel pump, resulting in the loss of all engine power and the pilot's failure to correctly execute an autorotational landing.
- [NTSB WPR11LA244](https://openairdocs.org/ntsb/WPR11LA244.md): Hiller UH-12E · Stockton, CA · Accident · No injuries · Limited investigation · Final report · Jun 1, 2011 · N68012 · Substantial damage
  > The pilot's failure to maintain clearance from obstacles.
- [NTSB WPR11CA146](https://openairdocs.org/ntsb/WPR11CA146.md): Hiller UH-12E · Colusa, CA · Accident · No injuries · Data collection · Final report · Feb 26, 2011 · N236HA · Substantial damage
  > The pilot's failure to maintain an adequate airspeed and an inadvertent encounter with settling with power while flying downwind.
- [NTSB WPR10CA466](https://openairdocs.org/ntsb/WPR10CA466.md): Hiller UH-12E · Mecca, CA · Accident · Minor injuries · Data collection · Final report · Sep 21, 2010 · N6053H · Substantial damage
  > The pilot's failure to maintain clearance from an obstacle while maneuvering.
- [NTSB WPR10LA127](https://openairdocs.org/ntsb/WPR10LA127.md): Hiller UH-12E · Los Banos, CA · Accident · No injuries · Limited investigation · Final report · Feb 2, 2010 · N36MV · Substantial damage
  > A partial loss of engine power due to a failure of the throttle interconnect hardware, which resulted in a hard landing.
- [NTSB WPR10CA094](https://openairdocs.org/ntsb/WPR10CA094.md): Hiller UH-12E · Tipton, CA · Accident · Minor injuries · Data collection · Final report · Jan 1, 2010 · N440NR · Substantial damage
  > The pilot's failure to maintain clearance from terrain.
- [NTSB LAX05CA313](https://openairdocs.org/ntsb/LAX05CA313.md): Hiller UH 12-E · Five Points, CA · Accident · No injuries · Data collection · Final report · Sep 22, 2005 · N141HA · Substantial damage
  > The pilot's failure to refuel the helicopter, which resulted in fuel exhaustion.
- [NTSB LAX01LA245](https://openairdocs.org/ntsb/LAX01LA245.md): Hiller UH-12E · Blythe, CA · Accident · No injuries · Limited investigation · Final report · Jul 13, 2001 · N9281P · Substantial damage
  > The selection by the pilot of an unsuitable precautionary landing site on soft, uneven terrain, which resulted in a rollover.
- [NTSB LAX00LA077](https://openairdocs.org/ntsb/LAX00LA077.md): Hiller UH-12E · Five Points, CA · Accident · No injuries · Limited investigation · Final report · Jan 26, 2000 · N68024 · Substantial damage
  > The pilot's inadequate clearance while maneuvering beneath a telephone line.
- [NTSB LAX00LA027](https://openairdocs.org/ntsb/LAX00LA027.md): Hiller UH-12E · Castroville, CA · Accident · Serious injuries · Limited investigation · Final report · Oct 28, 1999 · N5374V · Substantial damage
  > The pilot's inadequate visual lookout and diverted attention.
- [NTSB LAX99LA237](https://openairdocs.org/ntsb/LAX99LA237.md): Hiller UH-12ET · Williams, CA · Accident · No injuries · Limited investigation · Final report · Jun 30, 1999 · N7173F · Substantial damage
  > The pilot's inadequate preflight planning and verification that fuel was available for the intended flight. A factor was the fuel quantity false indication.
- [NTSB LAX99LA081](https://openairdocs.org/ntsb/LAX99LA081.md): Hiller UH-12E · Lemoore, CA · Accident · No injuries · Limited investigation · Final report · Jan 24, 1999 · N67064 · Substantial damage
  > The inadequate nature of the operator's maintenance, which failed to detect the primer and magneto discrepancies. An overly lean fuel mixture and/or magneto cross firing resulted in detonation, an ensuing connecting rod failure, and a total loss of engine…
- [NTSB LAX98LA089](https://openairdocs.org/ntsb/LAX98LA089.md): Hiller UH-12E · Chico, CA · Accident · No injuries · Limited investigation · Final report · Feb 13, 1998 · N4027Z · Substantial damage
  > Fuel exhaustion due to the pilot's failure to ensure that an adequate fuel supply was onboard. A contributing factor was related to the fuel quantity gage's erroneous indication of fuel.
- [NTSB LAX97LA179](https://openairdocs.org/ntsb/LAX97LA179.md): Hiller UH-12E · Truckee, CA · Accident · Serious injuries · Limited investigation · Final report · May 14, 1997 · N7082D · Substantial damage
  > A loss of engine power for undetermined reasons. A factor in the accident was the unsuccessful attempt to release the long line from the belly hook after it became entangled in a tree.
- [NTSB LAX96LA279](https://openairdocs.org/ntsb/LAX96LA279.md): Hiller UH-12E · Healdsburg, CA · Accident · No injuries · Limited investigation · Final report · Jul 20, 1996 · N124HA · Substantial damage
  > The failure of the pilot to confirm a loss of power before entering autorotation after reading an erroneous instrument indication on the helicopter's dual tachometer. Factors in the accident were the erratic instrument, and maintenance personnel who failed to…
- [NTSB LAX95LA318](https://openairdocs.org/ntsb/LAX95LA318.md): Hiller UH-12E · Dos Palos, CA · Accident · No injuries · Limited investigation · Final report · Sep 1, 1995 · N4027D · Substantial damage
  > the fatigue failure of the tail rotor tension torsion bar plates.
- [NTSB LAX95LA132](https://openairdocs.org/ntsb/LAX95LA132.md): Hiller UH-12E · Five Points, CA · Accident · No injuries · Limited investigation · Final report · Mar 12, 1995 · N172ET · Substantial damage
  > fuel exhaustion due to the pilot's inattention to the fuel supply.
- [NTSB LAX95LA109](https://openairdocs.org/ntsb/LAX95LA109.md): Hiller UH-12E · Arvin, CA · Accident · No injuries · Limited investigation · Final report · Feb 15, 1995 · N5335V · Substantial damage
  > The seizure of the transmission due to lack of lubrication from a plugged oil supply line.
- [NTSB LAX95LA096](https://openairdocs.org/ntsb/LAX95LA096.md): Hiller UH-12E · Chowchilla, CA · Accident · No injuries · Limited investigation · Final report · Feb 3, 1995 · N9293Z · Destroyed
  > the in-flight failure and separation of the main rotor hub due to a fatigue crack.
- [NTSB LAX95LA005](https://openairdocs.org/ntsb/LAX95LA005.md): Hiller UH-12E · Salinas, CA · Accident · Serious injuries · Limited investigation · Final report · Oct 13, 1994 · N145HA · Destroyed
  > an in-flight engine compartment fire for undetermined reasons.
- [NTSB LAX94LA054](https://openairdocs.org/ntsb/LAX94LA054.md): Hiller UH-12E · Salinas, CA · Accident · Minor injuries · Limited investigation · Final report · Nov 20, 1993 · N161HA · Substantial damage
  > a fatigue failure of the torsion-tension bar pin due to fretting corrosion. A factor in this accident was an inadequate quality of material utilized in the manufacture of the pin.
- [NTSB LAX94LA043](https://openairdocs.org/ntsb/LAX94LA043.md): Hiller UH-12E · Salinas, CA · Accident · No injuries · Limited investigation · Final report · Nov 13, 1993 · N149HA · Destroyed
  > The pilot's improper handling of the helicopter which resulted in overloading of the rotor system in a maneuvering turn during aerial application of chemical, and subsequent failure of the main rotor paddle assembly.
- [NTSB LAX93LA319](https://openairdocs.org/ntsb/LAX93LA319.md): Hiller UH-12E · Dixon, CA · Accident · Serious injuries · Limited investigation · Final report · Aug 11, 1993 · N100LM · Destroyed
  > the failure of the pilot to visually detect and avoid the guy wire.
- [NTSB LAX92LA401](https://openairdocs.org/ntsb/LAX92LA401.md): Hiller UH-12E · Coachella, CA · Accident · No injuries · Limited investigation · Final report · Sep 26, 1992 · N57BA · Substantial damage
  > The pilot's inadequate visual lookout and his failure to maintain an adequate clearance from the wires.
- [NTSB LAX92LA349](https://openairdocs.org/ntsb/LAX92LA349.md): Hiller UH12-E, Saloy Conver · Arvin, CA · Accident · Minor injuries · Limited investigation · Final report · Aug 15, 1992 · N9753C · Substantial damage
  > The failure of the tension torsion bar pin due to fatigue. Contributing to this accident was that it was not possible for the pilot to flare the helicopter on landing.
- [NTSB LAX92LA152](https://openairdocs.org/ntsb/LAX92LA152.md): Hiller UH-12E · Watsonville, CA · Accident · No injuries · Limited investigation · Final report · Mar 27, 1992 · N149HA · Substantial damage
  > A failure of the pilot to conduct an adequate pre-flight inspection of the aircraft to ensure that the fuel supply was free of contaminates. Contributing to this accident was fuel contamination.
- [NTSB LAX92LA146](https://openairdocs.org/ntsb/LAX92LA146.md): Hiller UH-12E · Huron, CA · Accident · No injuries · Limited investigation · Final report · Mar 21, 1992 · N93478 · Destroyed
  > A separation of the control rotor cuff due to fatigue.
- [NTSB LAX91LA249](https://openairdocs.org/ntsb/LAX91LA249.md): Hiller UH-12E · Huron, CA · Accident · No injuries · Limited investigation · Final report · Jun 7, 1991 · N507HA · Substantial damage
  > That unknown pilot(s) impoperly used the throttle control which caused an overspeed condition. Contributing to this accident was the connecting rod bolt fatigue failure.
- [NTSB LAX91LA191](https://openairdocs.org/ntsb/LAX91LA191.md): Hiller UH-12E · Delano, CA · Accident · No injuries · Limited investigation · Final report · May 4, 1991 · N4414 · Substantial damage
  > That the pilot improperly performed the autorotation by misjudging the flare altitude. Contributing to this accident was the total failure of the freewheeling sprag clutch due to excessive wear and the soft dirt terrain.
- [NTSB LAX90DVA08](https://openairdocs.org/ntsb/LAX90DVA08.md): Hiller UH-12-E · Los Banos, CA · Accident · Minor injuries · Final report · Aug 9, 1990 · N117HA · Destroyed
  > The pilot's failure to maintain a lookout for obstructions along his swath run.
- [NTSB LAX90DVA01](https://openairdocs.org/ntsb/LAX90DVA01.md): Hiller 12E · Huron, CA · Accident · Serious injuries · Final report · Oct 16, 1989 · N4026G · Substantial damage
  > The pilot failed to properly preflight the airplane before departing on the accident flight and misjudged the flare during the ensuing autorotation. Factors relating to this accident were oil starvation and total failure of the connecting rod.
- [NTSB LAX89DVM02](https://openairdocs.org/ntsb/LAX89DVM02.md): Hiller UH-12E · Salinas, CA · Accident · Minor injuries · Final report · Apr 26, 1989 · N169HA · Substantial damage
  > The separation of the torsion coupling in the main rotor drive system.
- [NTSB LAX88DVA16](https://openairdocs.org/ntsb/LAX88DVA16.md): Hiller UH-12E · Helm, CA · Accident · Minor injuries · Final report · Sep 10, 1988 · N4029Y · Substantial damage
  > During an aerial application flight, the pilot lost control of the helicopter just after liftoff and collided with the terrain. Inspection of the wreckage revealed that the chemical trucks filler hose was still attached to the helicopter when it lifted off.
- [NTSB LAX88DUG06](https://openairdocs.org/ntsb/LAX88DUG06.md): Hiller UH-12E · Thermal, CA · Accident · Minor injuries · Final report · Aug 17, 1988 · N65120 · Substantial damage
  > Shortly after refueling the helicopter & reloading the hopper, the plt took off & was starting to spray a field when the eng suddenly lost power. The plt said the helicopter was dscndg from about 30 ft when the power loss occurred; thus, he barely had time to…
- [NTSB LAX88DUM06](https://openairdocs.org/ntsb/LAX88DUM06.md): Hiller UH12E · Bard, CA · Accident · No injuries · Final report · Aug 3, 1988 · N14633 · Substantial damage
  > During helicopter aerial application, engine power was lost. Plt applied back cyclic and tail rotor contacted terrain, followed by hard landing. Investigation revealed less than useable fuel remaining.
- [NTSB LAX88DVA05](https://openairdocs.org/ntsb/LAX88DVA05.md): Hiller 12E · Firebaugh, CA · Accident · No injuries · Final report · May 9, 1988 · N117HA · Substantial damage
  > During an aerial application, the helicopter collided with a guy wire and then a field. The pilot knew that the wire was there. He stated that he simply forgot that it was there and did not see it. There were no mechanical problems prior to the accident.
- [NTSB LAX86FVA14](https://openairdocs.org/ntsb/LAX86FVA14.md): Hiller UH-12E · Lemoore, CA · Accident · Minor injuries · Final report · Sep 18, 1986 · N688SB · Substantial damage
  > The plt reptd that while returning to the loading area after spraying a field, he heard a loud pop emanating from the engine compartment. Shortly thereafter he observed a fire in the engine compartment and lost forward and aft control of the helicopter. The…
- [NTSB LAX86FVM08](https://openairdocs.org/ntsb/LAX86FVM08.md): Hiller UH 12E · Gonzales, CA · Accident · No injuries · Final report · Sep 7, 1986 · N149HA · Substantial damage
  > A loss of power was expereinced as the acft descended into a field at the beginning of an aerial application spray run. The plt initiated a forced landing into the field. During the landing the right skid dug into the field, tipping the helicopter onto its…
- [NTSB LAX86FVM06](https://openairdocs.org/ntsb/LAX86FVM06.md): Hiller UH21E · Salinas, CA · Accident · No injuries · Final report · Aug 12, 1986 · N169HA · Substantial damage
  > The plt experienced a 'ratcheting' to the right and a decrease in rotor RPM during cruise flt at 75-100 ft AGL. The plt made an autorotation but could not cushion the landing due to the low alt and lack of rotor RPM. The helicopter impacted hard and…
- [NTSB LAX86DVA09](https://openairdocs.org/ntsb/LAX86DVA09.md): Hiller UH-12E · Delano, CA · Accident · No injuries · Final report · Jun 17, 1986 · N172ET · Substantial damage
  > The helicopter rotor blade delaminated shortly after departing the operator's north base at Delano, CA. The investigation determined the blade contained extensive voids on the bond line. The blade was rejected by the manufacturer as being unairworthy. The…
- [NTSB LAX86FVM05](https://openairdocs.org/ntsb/LAX86FVM05.md): Hiller UH12E · Castroville, CA · Accident · Minor injuries · Final report · Apr 27, 1986 · N5374V · Destroyed
  > The acft landed hard and rolled over after the lndg skid failed in a forced lndg. The plt said he was crusing at 500 ft AGL over an open field when he heard a loud bang. The helicopter began to vibrate severely and spiral to the right. The plt lost ground…
- [NTSB LAX86LA113](https://openairdocs.org/ntsb/LAX86LA113.md): Hiller UH-12E · Lodi, CA · Accident · No injuries · Limited investigation · Final report · Feb 7, 1986 · N62421 · Substantial damage
  > While on an aerial agricultural spraying flight the acft engine lost total power. The plt executed an immediate autorotation landing. Upon ground contact, the acft skid for about 8 ft until the front skid contacted the ground furrow and nosed over causing the…
- [NTSB LAX85LA305](https://openairdocs.org/ntsb/LAX85LA305.md): Hiller UH-12E · Gonzales, CA · Accident · No injuries · Limited investigation · Final report · Jul 5, 1985 · N161HA · Substantial damage
  > While cruising during an ag flight the acft's eng began losing pwr. At the time the acft was about 50 ft AGL & was travelling at 50 mph. The plt made a forced ldg onto a nearby plowed fld. Upon touchdown the rt skid dug into a furrow & the acft rolled over.…
- [NTSB LAX85FA199](https://openairdocs.org/ntsb/LAX85FA199.md): Hiller UH12J3 · Klamath, CA · Accident · Serious injuries · Field investigation · Final report · Apr 12, 1985 · N545HA · Destroyed
  > The helicopter was returning to a private landing pad after a reconaisance flight prior to sprating. At about 10FT AGL after flaring and leveling the pilot could not control a drift and roll to the left. The rotor blades struck the ground within about one…
- [NTSB LAX85FA132](https://openairdocs.org/ntsb/LAX85FA132.md): Hiller UH12E · Five Points, CA · Accident · Minor injuries · Field investigation · Final report · Feb 3, 1985 · N5323V · Substantial damage
  > While performing an ag flight the helicopter's engin suddenly lost power. At the time the aircraft was near its max allowable gross weight and it was between 3-5FT AGL. As the aircraft yawed left and descended. The pilot in command attempted to land on a…
- [NTSB LAX85LA002](https://openairdocs.org/ntsb/LAX85LA002.md): Hiller UH-12E · Firebaugh, CA · Accident · Minor injuries · Limited investigation · Final report · Oct 5, 1984 · N161HA · Substantial damage
  > The acft collided with terrain while on an aerial application flt. The plt stated he, 'heard a loud bang' while spraying. Then the 'nose of the helicopter dove radically down', and he crashed into the field. Examination of the site revealed that one of the…

Next page: https://openairdocs.org/ntsb.md?model=4360122&state=CA&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."eventStateOrRegion" = 'CA' AND c."eventCountry" = 'USA'
  AND c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.aircraft_model_code IN ('4360122', '4360137'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?model=4360122&state=CA

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