# NTSB LAX88DVA16: Hiller UH-12E, N4029Y, Helm, CA, September 10, 1988

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Final report
- Date: September 10, 1988, 16:30 local (23:30 UTC)
- Place: Helm, CA
- Coordinates: 36.530929, -120.109001 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=36.5309&lon=-120.1090&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report November 24, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 25755
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX88DVA16
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/25755/pdf
- Page: https://openairdocs.org/ntsb/LAX88DVA16

## Sequence of events

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

- Loss of control - in flight, takeoff - initial climb
  - aircraft preflight - poor, pilot in command (cause)
  - diverted attention, pilot in command (contributing factor)
  - proper assistance - inadequate, ground personnel (cause)
  - habit interference, pilot in command (contributing factor)
  - aerial application equipment - engaged (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

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.

## Aircraft

- Registration: [N4029Y](https://openairdocs.org/deregistered/N4029Y-2018-02-13), registration cancelled 2018-02-13, S/N 5135, built 1980 (OpenAirDocs)
- Reported make and model: HILLER UH-12E
- Registry model: [Hiller UH-12E](https://openairdocs.org/model/hiller-uh-12e) (registry code 4360122) (OpenAirDocs)
- Registry engine: [Lycoming VO-540 series](https://openairdocs.org/engine/lycoming-vo-540-series) (registry code 41534, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: 5135
- Airframe hours: 3005
- Engines: LYCOMING VO-540-C2A 305 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Healy, Joseph G., doing business as Huron Ag Helicopters
- Registered owner: Russell W. Spencer
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, September 1, 1988, 47 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 43; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: center; flight hours: 5,500 total, 3,500 in this make and model, 5,000 as pilot in command, 120 in the last 90 days, 40 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 310° at 3 knots, gusting 5
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 84 °F

## 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 19880910038059A](https://openairdocs.org/incident/19880910038059A), Sep 10, 1988: Hiller UH12E, Helm, CA, Substantial damage. Failed to disconnect the chemical filler hose prior to liftoff from truck platform. Helicopter rolled over.

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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