Bell 206B accident near Oak Grove, Louisiana, August 23, 1997
On August 23, 1997 at about 2:00 pm local time, a Bell 206B (helicopter), registered N7929J, was substantially damaged in an accident near Oak Grove, Louisiana. It was an other work-use flight under external-load helicopter rules (Part 133). 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
The disconnect of the #5 tail rotor drive segment due to the debonding of the joint between the shaft tube and the flange fitting. Factors were the improper bead blasting of the tail rotor drive segment by an unknown maintenance personnel, and the lack of altitude and suitable terrain for the forced landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 23, 1997 · about 2:00 pm local time
- Place
- Oak Grove, Louisiana · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 206B · all 206Bs on the register
- Registration
- N7929J · no longer on the register · serial 663
- Damage
- Substantial damage
- Flight
- Other work-use flight · external-load helicopter rules (Part 133)
The NTSB's narrative final · quoted from the NTSB record
During an external load operation, the pilot was hovering the helicopter at about 60 feet above the boat, when the helicopter began to 'spin' to the right. He 'rolled off the throttle' and the spin stopped. He then maneuvered the helicopter to the right as it descended in an effort to clear the boat; however, the main rotor blades struck the front of the boat. Subsequently, the helicopter settled into the water and sank. Examination of the tail rotor drive system revealed that the #5 tail rotor drive shaft segment P/N 206-040-931-9 had separated at the bonded joint between the shaft tube and the flange fitting. Examination of this tail rotor drive segment by a metallurgist revealed that the separated joint revealed evidence of pitting which was indicative of plastic blast media impingement and the remaining adhesive had the consistency of powder/talc with no apparent structural integrity. According to the metallurgist the 'blast media impingement may effectively compromise the moisture barrier at the joint and allow the moist chloride environment to invade the joint and chemically degrade the adhesive.' Blast media impingement is not approved by Bell Helicopter.
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: airline transport pilot, commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instrument: helicopter; rotorcraft: helicopter
- Flight time: 7,000 hours in all; 1,800 in this make and model; 28 in the last 90 days; 12 in the last 30 days; 6,400 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 12,857 hours
- Last inspection: annual inspection, June 28, 1997; 81 hours since
- Maximum gross weight: 3,200 lb
- Seats: 5
- Landing gear: fixed
- Engine: Allison 250-C20B (turboshaft); 0 hours total
The flight
- Departed from: NONE Cameron LA at 1:50 pm
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 360° at 5 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 73°F (23°C), dew point 0°F (-18°C)
- Altimeter: 30.00 inHg
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.