Eurocopter AS350-B3 accident near Bishop, California, September 29, 2002
On September 29, 2002 at about 3:54 pm local time, a Eurocopter AS350-B3 (helicopter), registered N352SA, was substantially damaged in an accident near Bishop, California (Bishop airport). It was a public-use flight under public-use (government) rules. No one was hurt; 4 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
the disengagement of the collective locking mechanism due to component wear.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 29, 2002 · about 3:54 pm local time
- Place
- Bishop, California · Bishop · map
- Type
- Accident
- Injuries
- No one was hurt; 4 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Eurocopter AS350-B3 · all AS350-B3s on the register
- Registration
- N352SA · registry record · serial 3348
- Damage
- Substantial damage
- Flight
- Public-use flight · public-use (government) rules
The NTSB's narrative final · quoted from the NTSB record
The helicopter was performing a hydraulic actuator check for the first flight of the day. The collective had been placed in the down position, the collective lock was engaged, and the rotor powered up to 100 percent flight idle. After depressing the hydraulic test switch, the pilot moved the cyclic fore and aft to confirm there was pressure remaining in the accumulators for a few control movements. The collective rose uncommanded and the helicopter moved forward in a nose down attitude. The main rotor struck the ground and the helicopter made two revolutions before rolling over onto its side, destroying both the main and tail rotor systems. A small fire ensued in the exhaust area, but was quickly extinguished. Examination of the collective locking mechanism (P/N 350A-27 3455-20 and P/N 350A-27 3107-26) found that it failed to hold the collective in the full down position due to wear on the locking tab. During servo accumulator checks, movement of the cyclic control after accumulator depletion caused the collective to move due to feedback in the control system. The locking device disengaged and the collective increased causing the aircraft to move.
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, private
- Ratings: single-engine land; instructor: helicopter; instructor: instrument helicopter; instrument: helicopter; rotorcraft: helicopter
- Flight time: 3,000 hours in all; 350 in this make and model; 210 in the last 90 days; 37 in the last 30 days; 2,900 as pilot in command
- Last flight review: February 11, 2002
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: rgt
- Injury: minor injuries
The aircraft
- Airframe total time: 736 hours
- Last inspection: 100-hour inspection, August 16, 2002; 86 hours since
- Maximum gross weight: 4,961 lb
- Seats: 6
- Landing gear: fixed
- Engine: Turbomeca Arriel 1D1 (turboshaft); 0 hours total
- Fire on the ground
- Operator: US Dept Of Agriculture, US Forest Service
The flight
- Departed from: BIH Bishop CA at 4:58 pm
- Destination: O57 Bridgeport CA
- Flight plan: VFR
Weather at the time
- Light: daylight
- Wind: from 340° at 9 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 45°F (7°C), dew point 30°F (-1°C)
- Altimeter: 29.93 inHg
- Observation at 3:56 pm from KBIH
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 3 |
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.