# NTSB LAX83LA236: Hiller UH-12E, N4027L, Thermal, CA, May 18, 1983

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: May 18, 1983, 11:00 local (18:00 UTC)
- Place: Thermal, CA
- Coordinates: 33.480487, -116.099807 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=33.4805&lon=-116.0998&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 23717
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX83LA236
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/23717/pdf
- Page: https://openairdocs.org/ntsb/LAX83LA236

## Sequence of events

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

- Loss of engine power(total) - nonmechanical, maneuvering - aerial application
  - fluid,fuel - starvation (cause)
  - reason for occurrence undetermined (cause)
- Forced landing, landing - flare/touchdown
  - autorotation - performed, pilot in command (contributing factor)
- In flight collision with terrain/water, landing - flare/touchdown
  - object - vehicle (contributing factor)
  - maneuver - performed, pilot in command (contributing factor)
- Roll over, landing - flare/touchdown

## Analysis

THE PLT REPORTED THAT HE WAS APRX 1/3 OF THE WAY THRU A PROCEDURE TURN AT ABOUT 60 FT AGL, WHEN HE EXPERIENCED A PARTIAL POWER LOSS. HE COMPLETED THE TURN, LEVELED THE HELICOPTER & MOUMENTARILY REGAINED COMPLETE POWER, THEN THE ENGINE QUIT OPERATING. AN AUTOROTATIVE LANDING TO A ROAD WAS STARTED, BUT THE PLT SAW A TRUCK APPROACHING, SO HE MANEUVERED BACK TOWARD THE FIELD THAT HE HAD BEEN SPRAYING. DURING THE LANDING FLARE, THE TAIL ROTOR STRUCK THE GROUND. SUBSEQUENTLY, THE PLT LOST CONTROL OF THE HELICOPTER & IT CAME TO REST ON ITS RIGHT SIDE. DURING AN INVESTIGATION, THE AUXILIARY FUEL PUMP HAD TO BE PRIMED BEFORE THE ENG WOULD START. REPORTEDLY, A FUEL INTERUPTION TO THE PUMP COULD CAUSE IT TO LOSE ITS PRIME, & IF THIS OCCURRED DURING FLT, FUEL STARVATION WOULD OCCUR. THE PLT STATED THAT HE HAD MADE CYCLIC TURNS TO KEEP POSTITIVE G'S ON THE ROTOR SYSTEM RATHER THAN CYCLIC & PEDAL TURNS. APRX GAL OF FUEL WAS REMAINING.

## Aircraft

- Registration: [N4027L](https://openairdocs.org/deregistered/N4027L-2002-06-17), registration cancelled 2002-06-17, S/N 5074, built 1979 (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: 5074
- Airframe hours: 951
- Engines: LYCOMING VO540-C2A 305 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Registered owner: J & J Helicopter
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, December 20, 1982, 74 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 43; commercial, airline transport, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: center; flight hours: 8,050 total, 4,800 in this make and model, 7,790 as pilot in command, 183 in the last 90 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 240° at 5 knots
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 91 °F
- Altimeter: 29.00 inHg
- Observed at: TRM, 5 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 19830518056779A](https://openairdocs.org/incident/19830518056779A), May 18, 1983: Hiller UH12E, Thermal, CA, Substantial damage. Crash occurred during emergency landing after engine lost power during procedure turn.

## Other investigations on N4027L (1)

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.

- [NTSB CHI98LA012](https://openairdocs.org/ntsb/CHI98LA012), Oct 9, 1997: Hiller UH-12E (N4027L), Liberty, NE, substantial damage. Probable cause: A loss of engine power for undetermined reasons.

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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