Bell 47G-3B-1 accident near Yuma, Arizona, April 17, 1994
On April 17, 1994 at about 3:00 am local time, a Bell 47G-3B-1 (helicopter), registered N304JP, was substantially damaged in an accident near Yuma, Arizona. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
an uncommanded engine deceleration to idle due to the improper installation of the throttle arm on the carburetor shaft.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 17, 1994 · about 3:00 am local time
- Place
- Yuma, Arizona · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 47G-3B-1 · all 47G-3B-1s on the register
- Registration
- N304JP · no longer on the register · serial 3598
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
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.'
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: single-engine land; instructor: helicopter; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 15,163 hours in all; 6,500 in this make and model; 167 in the last 90 days; 46 in the last 30 days; 14,637 as pilot in command; 1,447 on instruments
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 15,222 hours
- Last inspection: 100-hour inspection, April 4, 1994; 23 hours since
- Maximum gross weight: 2,950 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming V0-435-AIF (piston); 0 hours total
- Operator: Sundown Helicopters, INC.
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: dusk
- Wind: from 320° at 2 knots
- Visibility: 40 statute miles
- Sky: clear
- Temperature: 72°F (22°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.