- Date
- April 16, 1994, 20:00 local (Apr 17, 1994, 03:00 UTC)
- Place
- Yuma, AZ
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N304JPBell 47G-3B-1
- Weather
- Visual (VMC) · Dusk
- Status
- Completed · report November 14, 1994
- Report
- Approved by Office Director
- FAA report
- 19940416009079A
- Case key
- 28727
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
an uncommanded engine deceleration to idle due to the improper installation of the throttle arm on the carburetor shaft.
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.
Analysis
The pilot reported that the helicopter had completed a swath run and was pulling up to clear a line of trees when the engine decelerated to idle. The pilot entered an autorotation and landed hard, damaging the skids and the fuselage. Postaccident inspection of the engine revealed that the throttle arm had come off the carburetor throttle body shaft. The operator stated that the arm and shaft were new components, installed on February 24, 1994, by a contract mechanic. The operator also stated that an 'excessive amount (about 2 inches) of safety wire was on the arm, which allowed the arm to slip off the shaft.'
Factual narrative
On April 16, 1994, at 2000 mountain standard time, a Bell 47G-3B- 1 helicopter, N304JP, landed hard following a loss of engine power while engaged in aerial application operations near Yuma, Arizona. The helicopter was owned and operated by Sundown Helicopters, Inc., of Yuma, Arizona, under the provisions of 14 CFR Part 137 of the Federal Aviation Regulations. Visual meteorological conditions prevailed at the time and no flight plan was filed for the operation. The aircraft incurred substantial damage. The certificated commercial pilot, the sole occupant, was not injured. The flight originated from the field to be sprayed about 1915 hours on the day of the accident.
The operator and pilot reported that the helicopter had completed a swath run and was pulling up to clear a line of trees when the engine decelerated to idle. The pilot entered an autorotation and landed hard, damaging the skids and the fuselage.
Postaccident inspection of the engine revealed that the throttle arm had come off the carburetor throttle body shaft. The operator stated that the arm and shaft were new components, installed on February 24, 1994, by a contract mechanic. The operator also stated that an "excessive amount (about 2 inches) of safety wire was on the arm, which allowed the arm to slip off the shaft."
Aircraft
- Registration
- N304JP
- Reported as
- Bell 47G-3B-1
- Category
- Helicopter
- Serial number
- 3598
- Airframe hours
- 15,222
- Engine
- Lycoming V0-435-AIF, 260 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Aerial application · Part 137
- Operator
- Sundown Helicopters, Inc.
- Registered owner
- Sundown Helicopters, Inc.
- Airworthiness certificate
- Special, Restricted (Special)
- Last inspection
- 100 hour · April 4, 1994 · 23 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
- 47
- Certificates
- Flight instructor, Commercial
- Airplane ratings
- Single-engine land
- Instrument ratings
- Airplane, Helicopter
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Left
- Flight hours
- 15,163 total · 6,500 in this make and model · 14,637 as pilot in command · 167 in the last 90 days · 46 in the last 30 days · 3 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Dusk
- Wind
- 320° at 2 knots
- Visibility
- 40 statute miles
- Lowest ceiling
- None
- Temperature
- 72 °F
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.