# NTSB LAX86LA242: Hiller UH-12E, N8503W, Thermal, CA, June 6, 1986

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Limited investigation · Final report
- Date: June 6, 1986, 09:22 local (16:22 UTC)
- Place: Thermal, CA
- Coordinates: 33.479026, -116.100715 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=33.4790&lon=-116.1007&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal, 1 minor; on the ground: 1 minor
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 25175
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX86LA242
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/25175/pdf
- Page: https://openairdocs.org/ntsb/LAX86LA242

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- In flight collision with terrain/water, maneuvering - aerial application
  - reason for occurrence undetermined (cause)

## Analysis

THE HELICOPTER COLLIDED WITH TERRAIN DURING A MANEUVERING TURN WHILE APPLYING A PESTICIDE TO A CULTIVATED FIELD. THE ACFT WAS SEEN ON THE PASS JUST PRIOR TO THE ACCIDENT AND THE ACFT APPEARED TO BE LOWER THAN USUAL. THE ACFT WAS DESTROYED BY POST-IMPACT FIRE.

## Aircraft

- Registration: [N8503W](https://openairdocs.org/deregistered/N8503W-1988-08-16), registration cancelled 1988-08-16, S/N 1484 (OpenAirDocs)
- Reported make and model: HILLER UH-12E
- Registry model: [Hiller-Roberts OH23G](https://openairdocs.org/model/hiller-roberts-oh23g) (registry code 4362305) (OpenAirDocs)
- Category: Helicopter
- Serial number: 1484
- Engines: LYCOMING VO-540-B1A 305 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Aerial application, Part 137
- Registered owner: John B. Bilbrey
- Airworthiness certificate: Special, Restricted (Special)
- Departed: THERMAL, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 46; airline transport; airplane ratings: multi-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 11,000 total

## Weather

- Conditions: Visual (VMC), Day
- Wind: 300° at 5 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 84 °F, dew point 55 °F
- Altimeter: 29.00 inHg
- Observed at: TRM, 4 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19860606021929A](https://openairdocs.org/incident/19860606021929A), Jun 6, 1986: Hiller OH23G, Thermal, CA, Destroyed. The helicopter impacted the ground during spray operations. Record of careless use of toxic chemicals by operator.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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