Messerschmitt-Boelkow-Blohm BO-105S accident near Thibodaux, Louisiana, September 6, 2009
On September 6, 2009 at about 7:00 pm local time, a Messerschmitt-Boelkow-Blohm BO-105S (helicopter), registered N131EH, was substantially damaged in an accident during maneuvering (hover) near Thibodaux, Louisiana (Thibodaux Municipal airport). It was an other work-use flight under general aviation rules (Part 91). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's inability to maintain control due to the mechanic's inadvertent switching of two cyclic control tubes of different lengths during maintenance.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 6, 2009 · about 7:00 pm local time
- Place
- Thibodaux, Louisiana · Thibodaux Municipal · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Messerschmitt-Boelkow-Blohm BO-105S · all BO-105Ss on the register
- Registration
- N131EH · no longer on the register · serial S-595
- Damage
- Substantial damage
- Flight
- Other work-use flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
While in a 3-foot hover the helicopter began an uncommanded roll to the right. The pilot unsuccessfully attempted to arrest the roll by applying full left cyclic. Moments later the right landing skid made contact with the ground, followed by the main rotor blades. The helicopter came to rest in a right-side-low, upright position and the pilot was able to exit unassisted. The purpose of the flight was to perform an operational flight check of maintenance performed to the cyclic control system. The investigation revealed that the mechanic who had performed the maintenance had inadvertently switched two cyclic control tubes, of different lengths, during reassembly. This resulted in an out-of-rig condition in the cyclic control system. No other preimpact anomalies were noted with the helicopter's flight control system.
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
What happened, in order
- Aircraft maintenance event during prior to flight
- Flight control sys malf/fail during maneuvering (hover) defining event
- Loss of control in flight during maneuvering (hover)
- Collision with terrain or object (not controlled flight into terrain) during uncontrolled descent
The NTSB's findings
- cause Aircraft › Aircraft systems › Flight control system › (general) › Incorrect service/maintenance
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › (general) › Attain/maintain not possible
- cause Personnel issues › Task performance › Maintenance › Installation › Maintenance personnel
Pilot
- Certificate: airline transport pilot
- Ratings: instrument: helicopter; rotorcraft: helicopter
- Flight time: 10,033 hours in all; 1,969 in this make and model
- Last flight review: August 13, 2009
- Medical certificate: Class 1 (with waivers/limitations)
- Seat: rgt
- Injury: minor injuries
The aircraft
- Airframe total time: 16,155 hours
- Last inspection: continuous airworthiness programme, May 15, 2009
- Maximum gross weight: 5,731 lb
- Seats: 5
- Landing gear: fixed
- Engine 1: Allison 250-C20B (turboshaft); 0 hours total
- Engine 2: Allison 250-C20 SER (turboshaft); 0 hours total
- Operator: Era Helicopters LLC
The flight
- Departed from: L83 Thibodaux LA at 7:00 pm
- Destination: L83 Thibodaux LA
Weather at the time
- Light: daylight
- Wind: from 270° at 5 knots
- Visibility: 10 statute miles
- Sky: overcast; scat at 2,000 ft
- Temperature: 84°F (29°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight 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.