FTW96LA315

NTSB accident investigation · Hiller UH-12E · Mount Holly, AR · July 24, 1996

Accident · Serious injuriesLimited investigationFinal report
Date
July 23, 1996, 19:13 local (Jul 24, 1996, 00:13 UTC)
Place
Mount Holly, AR
Injuries
1 serious
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N9743CHiller UH-12E
Weather
Visual (VMC) · Dusk
Status
Completed · report February 18, 1997
Report
Approved by Office Director
FAA report
19960723019609A
Case key
19919

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

On this page

Probable cause

Fuel exhaustion due to the pilot's failure to refuel the helicopter. A factor was the lack of suitable terrain for the forced landing.

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.

Loss of engine power(total) - nonmechanicalManeuvering - aerial application
Fluid,fuel - exhaustionCause
Refueling - not performedPilot in commandCause
Forced landingEmergency descent/landing
Autorotation - performedPilot in command
In flight collision with terrain/waterEmergency descent/landing
Terrain condition - none suitableFactor
Object - tree(s)

Analysis

The helicopter came to rest on its side in a heavily wooded area during a forced landing following a loss of engine power. The pilot put 20 gallons of fuel in the helicopter the day prior to the accident. The helicopter was on its seventh load when it crashed, and it had not been refueled. The fuel tank holds 46 gallons of fuel and the engine uses approximately '28 gallons per hour during some ag operation maneuvers.' Examination of the accident site and helicopter revealed no evidence of fuel.

Factual narrative

On July 23, 1996, at 1913 central daylight time, a Hiller UH-12E, N9743C, registered to and operated by Summit Helicopters Inc., sustained substantial damage during a forced landing, following a loss of power near Mount Holly, Arkansas. The airline transport rated pilot was seriously injured. Visual meteorological conditions prevailed for the Title 14 CFR Part 137 aerial application flight. A flight plan was not filed for the local flight.

The pilot reported to the investigator-in-charge that the helicopter was fueled with 20 gallons of fuel on July 22, 1996, and "there was no flying until the afternoon of the 23rd." He further reported that he "remembers little, to nothing, of the events of that day." He also reported that his wife was performing duties of "swamper," and "that at the time of loading the 7th load she had glanced at [the] fuel gauge and saw it indicated about 1/2 tank."

The helicopter retrieval truck driver reported that on Monday afternoon, the pilot put 20 gallons of fuel in the helicopter, and it did not fly until Tuesday afternoon. He further reported that the helicopter was on its seventh "load" when it crashed, and it had not been refueled.

The operator reported that during recovery of the helicopter that there was no odor of fuel around the aircraft, and no sign of fuel spillage. While digging down approximately six inches into the ground around the entire crash site, no evidence of fuel was found.

The operator further reported that examination of the engine revealed that the power turbine turned the compressor freely. Their examination of the fuel pump filter and fuel lines revealed no fuel present. Less than one gallon of fuel was found in the fuel tank and the tank was not ruptured.

The operator also reported the following information. When the battery was connected, the fuel gauge indicated empty. Their procedures do not consider the gauge accurate or reliable therefore, they "stick" the tank to determine fuel quantity. "Normal procedures" for this company "is to spray three loads and then refuel." The helicopter fuel tank holds 46 gallons of fuel and the engine uses approximately "28 gallons per hour during some ag operation maneuvers."

The aircraft had an annual inspection completed on April 16, 1996. Several 25 hour inspections, and a 100 hour inspection had been complied with since the date of the annual. No unusual or recurring maintenance discrepancies were noted during the review of the aircraft records by the FAA inspector.

Examination of the accident site by the FAA inspector revealed that the helicopter came to rest on its left side in a heavily wooded area. During a walk-around of the accident site, no odor or other indication of a fuel spill was present. Examination of the aircraft revealed that the main rotor blades were damaged, and the main rotor mast was damaged and bent. The tail section was substantially damaged, and part of it was separated and found approximately 30 to 35 feet from the main wreckage.

Aircraft

Registration
N9743C
Reported as
Hiller UH-12E
Category
Helicopter
Serial number
2141
Airframe hours
12,019
Engine
Allison 250-C20B, 305 horsepower, turbo shaft
Damage
Substantial damage
Flight
Aerial application · Part 137
Registered owner
Summit Helicopters Inc
Airworthiness certificate
Standard, Normal; Special, Restricted (Special)
Last inspection
100 hour · June 21, 1996 · 64 hours before

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
56
Certificates
Airline transport, Commercial
Airplane ratings
Multi-engine land, Single-engine sea, Single-engine land
Instrument ratings
Helicopter, Airplane
Medical
Class 2, Valid Medical--w/ waivers/lim
Seat
Left
Flight hours
8,403 total · 3,000 in this make and model

Weather

Conditions
Visual (VMC) · Dusk
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
88 °F, dew point 77 °F

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 N9743C · 2

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