WPR11LA267

NTSB accident investigation · Hiller UH-12E · Lost Hills, CA · June 19, 2011

Accident · Minor injuriesLimited investigationFinal report
Date
June 19, 2011, 07:20 local (14:20 UTC)
Place
Lost Hills, CA
Injuries
1 minor
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N138HAHiller UH-12E
Defining event
Maneuvering-low-alt flying: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed · report October 4, 2011
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
Fresno FSDO
FAA report
20110619012689A
Case key
80817

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 engine-driven fuel pump, resulting in the loss of all engine power and the pilot's failure to correctly execute an autorotational landing.

Findings · 4

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Fuel system: fuel pumpsAircraft › Aircraft systems · FailureHiller UH-12E: 1 caseAll aircraft: 71 casesProbable cause
Action: incorrect action performancePersonnel issues › Action/decision · PilotHiller UH-12E: 3 casesAll aircraft: 1,386 casesProbable cause
Performance/control parameters: prop/rotor parametersAircraft › Aircraft oper/perf/capability · Not attained/maintainedHiller UH-12E: 2 casesAll aircraft: 182 casesProbable cause
Use of equip/info: aircraft controlPersonnel issues › Task performance · PilotHiller UH-12E: 7 casesAll aircraft: 9,295 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

During a helicopter agricultural spray operation, the pilot ascended to about 100 feet above ground level (agl) to make a downwind turn. During that sequence of events, the engine-driven fuel pump failed, resulting in the loss of all engine power. The pilot immediately entered autorotation, and attempted a power-off landing in a field of alfalfa. During landing, the pilot applied up collective too early, and the main rotor blade ran out of autorotational energy while the helicopter was still about 10 feet above the ground. The helicopter landed hard which resulted in substantial damage to the airframe. A postaccident teardown inspection of the helicopter's fuel system determined that the engine driven fuel pump could not be turned by hand, that its internal metallic surfaces were galled, and that it was contaminated with loose metal particles. The inspection also determined that the 24 volt electrically-powered auxiliary fuel pump was internally seized and could not be turned by hand.

Factual narrative

On June 19, 2011, about 0720 Pacific daylight time, a piston engine-powered Hiller UH-12E helicopter, N138HA, experienced a hard landing in an agricultural field near Lost Hills, California. The commercial pilot, who was the sole occupant, received minor injuries, and the helicopter, which was owned and operated by the pilot, sustained substantial damage. The 14 Code of Federal Regulations Part 137 aerial application flight, which departed a local refueling site about 15 minutes prior to the accident, was being conducted in visual meteorological conditions. No flight plan had been filed. According to the pilot, after making a spray pass during which he applied chemicals to an agricultural field, he ascended to about 100 feet above ground level (agl) in order to make a downwind turn. At that time the helicopter's engine suddenly stopped producing power. Because of his height above the ground, the pilot immediately entered an autorotational descent in order to attempt a forced landing. According to the pilot, during the landing sequence, he applied up collective in order to slow the descent rate and initiate the landing flare, but the main rotor blades ran out of energy to produce lift while the helicopter was still about 10 feet above the ground. It therefore landed hard in an alfalfa field, and the impact resulted in substantial damage to both the main rotor blades and the airframe. A postaccident teardown inspection of the helicopter's fuel system determined that the engine driven fuel pump could not be turned by hand, that its internal metallic surfaces were galled, and that it was contaminated with loose metal particles. The inspection also determined that the 24 volt-powered auxiliary fuel pump had failed and could not be turned by hand.

Aircraft

Registration
N138HA
Reported as
Hiller UH-12E
Category
Helicopter
Serial number
HA3038
Airframe hours
8,570
Engine
Lycoming TIO-540 SER, 310 horsepower, reciprocating
Damage
Substantial damage
Flight
Aerial application · Part 137
Operator
Slikker Flying Service, doing business as Vince Dusters
Registered owner
Slikker Flying Service
Airworthiness certificate
Special, Restricted (Special)
Last inspection
100 hour · March 24, 2011
Departed
Lost Hills, CA
Destination
Lost Hills, CA

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
50
Injuries
Minor
Certificate
Commercial
Airplane ratings
Single-engine land
Medical
Class 2, With waivers/limitations
Last flight review
April 3, 2011
Seat
Center
Flight hours
9,567 total · 7,800 in this make and model · 9,432 as pilot in command

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
73 °F, dew point 48 °F
Altimeter
29.77 inHg

Docket · 2

The files NTSB released with the investigation on August 18, 2011, on NTSB’s docket system: statements, records, photos and specialists’ reports. 160 KB in all.

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 N138HA · 2

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