SEA03LA023

NTSB accident investigation · Bell 47G · Idaho Falls, ID · January 2, 2003

Accident · No injuriesLimited investigationFinal report
Date
January 2, 2003, 09:00 local (16:00 UTC)
Place
Idaho Falls, ID
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N4759RBell 47G
Weather
Visual (VMC) · Day
Status
Completed · report December 30, 2003
Report
Approved by Office Director
Parties
FAA-FSDO
FAA report
20030102000079A
Case key
56270

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

In-flight loss of engine power for undetermined reasons.

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 powerCruise
Reason for occurrence undeterminedCause
Forced landingDescent - emergency
In flight collision with terrain/waterEmergency landing
Terrain condition - open field

Analysis

The pilot reported that while in a cruise flight configuration, at 5,100 feet MSL and 80 MPH, the helicopter experienced a loss of engine power and the pilot initiated a forced landing to a nearby alfalfa field. During the landing, the main rotor blades made contact with the tail boom assembly, severing the top two tubes just aft of the last hangar bearing. Visual inspection of the helicopter's engine and associated components revealed no evidence of atypical wear or component failure. Following the visual inspection, the operator conducted an engine run. The engine was started and ran at various power settings for approximately 10 minutes. No power surges or anomalies were noted during test run.

Factual narrative

On January 02, 2003, about 0900 mountain standard time, a turbine converted Bell 47G helicopter, N4759R, sustained substantial damage after a loss of engine power, autorotation, and hard landing eight miles southeast of Idaho Falls, Idaho. The helicopter is owned and operated by Heli-Wood of Tremonton, Utah, and was being operated as a visual flight rules (VFR) positioning flight in accordance with Title 14, CFR Part 91, when the accident occurred. The commercial pilot, the sole occupant of the helicopter, was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the flight. The flight originated from an off-airport site approximately five miles east of Idaho Falls, approximately six minutes prior to the accident.

The pilot reported that while in a cruise flight configuration, at 5,100 feet MSL and 80 MPH, the helicopter experienced a loss of engine power and the pilot initiated a forced landing to a nearby alfalfa field. During the landing, the main rotor blades made contact with the tail boom assembly, severing the top two tubes just aft of the last hangar bearing.

Visual inspection of the helicopter's engine and associated components revealed no evidence of atypical wear or component failure. Inspection of the fuel system revealed that: the fuel inlet lines and vent lines were intact and no restrictions or leakage was noted. The fuel pump filter, airframe fuel filter, fuel control inlet screen and fuel nozzle inlet screen were intact and free of contaminants. Soot and carbon deposits were noted on the fuel nozzle tip. The Pc lines and associated components were intact and no cracks or evidence of leakage was noted.

Following the visual inspection, the operator conducted an engine run. The engine was started and ran at various power settings for approximately 10 minutes. No power surges or anomalies were noted during test run.

The operator and a representative from the Salt Lake City Flight Standards District Office conducted the post accident inspection and subsequent test run.

Aircraft

Registration
N4759R
Reported as
Bell 47G
Category
Helicopter
Serial number
6728
Airframe hours
11,053
Engine
Allison C20 B, 280 horsepower, turbo shaft
Damage
Substantial damage
Flight
Other work use · Part 91
Registered owner
Heli-Wood
Airworthiness certificate
Standard, Normal
Last inspection
Annual · November 3, 2002 · 60 hours before
Departed
IDA · Idaho Falls, ID

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
53
Injuries
None
Certificate
Commercial
Medical
Class 2, Valid Medical--no waivers/lim.
Last flight review
December 9, 2002
Seat
Left
Flight hours
19,000 total · 18,900 in this make and model · 18,850 as pilot in command

Weather

Conditions
Visual (VMC) · Day
Wind
320° at 4 knots
Visibility
9 statute miles
Lowest ceiling
4,200 ft broken
Temperature
21 °F, dew point 21 °F
Altimeter
30.38 inHg
Observed at
KIDA, 8 nm away

Docket · 1

The files NTSB released with the investigation on November 12, 2003, on NTSB’s docket system: statements, records, photos and specialists’ reports. 278 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.