Eurocopter France AS 350 B3 accident near Yuma, Arizona, November 25, 2003
On November 25, 2003 at about 2:00 am local time, a Eurocopter France AS 350 B3 (helicopter), registered N846BP, was substantially damaged in an accident near Yuma, Arizona (Yuma Mcas International airport). It was a public-use flight under public-use (government) rules. No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
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The NTSB's probable cause their words, unchanged
The malfunction of the rotor drive system due to improper maintenance, which resulted in the uncoupling of the drive shaft during takeoff-initial climb. A factor associated with the accident is the undertorqued drive system bolts.
Source: NTSB aviation accident database, copy made October 4, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 25, 2003 · about 2:00 am local time
- Place
- Yuma, Arizona · Yuma Mcas International · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Eurocopter France AS 350 B3 · all AS 350 B3s on the register
- Registration
- N846BP · registry record · serial 3542
- Damage
- Substantial damage
- Flight
- Public-use flight · public-use (government) rules
The NTSB's narrative final · quoted from the NTSB record
The helicopter encountered a total loss of drive to the rotor system a few seconds after takeoff, about 20 feet above the ground. The helicopter touched down hard and was substantially damaged. Company mechanics had performed maintenance on the helicopter that involved handling of the rotor drive shaft and a flex coupling. The flex coupling is normally secured with three bolts and self locking nuts. The manufacturer's maintenance procedure requires that during installation, the nuts are torqued and then cotter pins are inserted. During the wreckage examination, the bolts were found sheared, and no evidence of cotter pins were found. According to the manufacturer, even if the cotter pins are not installed, if the bolts are adequately torqued, they should not become loose.
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: commercial pilot
- Ratings: single-engine land; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 6,273 hours in all; 202 in this make and model; 250 in the last 90 days; 60 in the last 30 days; 4,921 as pilot in command; 0 on instruments
- Last flight review: July 10, 2003
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: rgt
- Injury: minor injuries
The aircraft
- Airframe total time: 813 hours
- Last inspection: 100-hour inspection, November 20, 2003; 13 hours since
- Maximum gross weight: 4,961 lb
- Seats: 6
- Landing gear: fixed
- Engine: Turbomeca Arriel A2 (turboshaft); 0 hours total
The flight
- Departed from: YUM Yuma AZ at 1:59 am
- Destination: YUM
- A second pilot was aboard
Weather at the time
- Light: night, bright
- Wind: from 040° at 6 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 12,000 ft; a few clouds at 6,000 ft
- Temperature: 61°F (16°C), dew point 19°F (-7°C)
- Altimeter: 29.88 inHg
- Observation at 1:56 am from YUM
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
About this page
Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The docket at the NTSB holds the report as a PDF and the investigation's photographs and documents. This site never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number LAX04TA052.