LAX93LA319

NTSB accident investigation · Hiller UH-12E · Dixon, CA · August 11, 1993

Accident · Serious injuriesLimited investigationFinal report
Date
August 11, 1993, 10:45 local (17:45 UTC)
Place
Dixon, CA
Injuries
1 serious
Damage
Destroyed
Phase of flight
Maneuvering
Aircraft
N100LMHiller UH-12E
Weather
Visual (VMC) · Day
Status
Completed · report June 30, 1994
Report
Approved by Office Director
FAA report
19930811029049A
Case key
28444

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

the failure of the pilot to visually detect and avoid the guy wire.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

In flight collision with objectManeuvering - aerial application
Object - wire,static
Visual lookout - inadequatePilot in commandCause
Nose overLanding
Precautionary landing - performedPilot in command
Terrain condition - soft
Terrain condition - high vegetation

Analysis

An FAA inspector said the helicopter had been working the field for about 2 hours dispensing insecticides. The pilot departed the truck after refueling to finish the remaining corner of the field being sprayed. The field is bordered by a set of power lines on wooden poles with a wire height about 40 feet AGL. The pilot was flying under the power lines during his spray runs. The last two poles had a one quarter inch guy wire strung between them about half way up the poles. On the final pass in the field, the helicopter collided with the guy wire. Based on his inspection of the wreckage and witness observations, the FAA inspector reported that the helicopter collided with the wire at a point between the rotor hub and the swash plate assembly, breaking the pitch change links. The pilot was able to regain partial control of the helicopter and was attempting a run on landing cross furrow in a tomato field about two miles from the wire strike. The helicopter skids caught on both the plants and the soft furrows and tumbled to a stop.

Factual narrative

On August 11, 1993, at 1045 Pacific daylight time, a Hiller UH- 12E helicopter, N100LM, collided with a guy wire strung between two power poles and crashed while attempting a forced landing in a field near Dixon, California. The aircraft was operated by Pacific Valley Aviation, Inc., Arbuckle, California, and was on an aerial application flight dispensing insecticides at the time. Visual meteorological conditions prevailed at the time and no flight plan was filed for the operation. The aircraft was demolished in the collision sequence. The certificated commercial pilot, the sole occupant, sustained serious injuries. The flight originated from a truck near the accident site at about 1025 hours on the day of the mishap.

An FAA inspector from the Sacramento, California, Flight Standards District Office examined the aircraft and the accident site, and, in addition, interviewed witnesses to the accident. In his report, the inspector said the helicopter had been working the field for about two hours dispensing insecticides. The pilot departed the truck after refueling to finish the remaining corner of the field being sprayed. The field is bordered by a set of power lines on wooden poles with a wire height about 40 feet AGL. The pilot was flying under the power lines during his spray runs. The last two poles had a one quarter inch guy wire strung between them about half way up the poles. On the final pass in the field, the helicopter collided with the guy wire.

Based on his inspection of the wreckage and witness observations, the inspector reported that the helicopter collided with the wire at a point between the rotor hub and the swash plate assembly, breaking the pitch change links. The pilot was able to regain partial control of the helicopter and was attempting a run on landing cross furrow in a tomato field about two miles from the wire strike. The helicopter skids caught on both the plants and the soft furrows and tumbled to a stop.

Aircraft

Registration
N100LM
Reported as
Hiller UH-12E
Category
Helicopter
Serial number
1583
Airframe hours
7,635
Engine
Allison 250 C20B, 420 horsepower, turbo shaft
Damage
Destroyed
Flight
Aerial application · Part 137
Operator
Pacific Valley Aviation, Inc.
Registered owner
Jim & Carol Miller
Airworthiness certificate
Standard, Normal
Last inspection
Continuous airworthiness · August 8, 1993 · 9 hours before
Departed
NONE
Destination
NONE

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
34
Certificate
Commercial
Airplane ratings
Single-engine land
Medical
Class 2, Valid Medical--no waivers/lim.
Seat
Center
Flight hours
6,500 total · 650 in this make and model · 6,000 as pilot in command · 90 in the last 90 days · 40 in the last 30 days · 8 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
240° at 6 knots
Visibility
25 statute miles
Lowest ceiling
None
Temperature
66 °F, dew point 54 °F
Altimeter
30.00 inHg

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.

Other investigations on N100LM · 2

Matched to the same aircraft by N-number and date.