Bell 206B N7131U

Summary

On 1 June 1999 at about 19:48 local time, a Bell 206B registered N7131U was involved in an accident near Venice, Louisiana, United States. 3 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

1 June 1999 at 19:48

Classification

Accident

Location

Venice, Louisiana, United States

Coordinates

29.2705, -89.3501

Aircraft

Bell 206B

Registration

N7131U

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Aerial Observation

Phase of flight

Not recorded

Route

West Delta 30 → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

FTW99LA155

Nobody was injured.

The pilot's improper touchdown procedure, resulting in a main rotor blade contacting the tailboom. Factors were the soft and wet terrain conditions, and the loss of engine power due to the spiral fatigue failure of the gas generator turbine shafting due to spline wear.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

About 150 feet agl and 60 knots, as the helicopter was accelerating, the pilot heard a loud 'bang,' and the low rotor rpm and engine out audio warning activated. The pilot initiated an autorotation to a grassy area, 'flared the aircraft, and placed it in six to eight inches of water.' A main rotor blade contacted the tailboom, partially separating it aft of the horizontal stabilizer. A passenger reported that the pilot 'pulled pitch right before the landing and we landed with one medium bump and then followed very quickly with another medium bump with a loud sound with it.' The passenger further reported that the landing attitude was 'relatively normal;' however, 'it was possibly a little more pitched up than normal.' An examination of the engine revealed that the Spur Adapter Gearshaft was fractured at the forward splines. According to the engine manufacturer's metallurgist, 'severe spline wear led to [the] spiral fatigue failure of the Spur Adapter Gearshaft and Compressor Adapter Coupling.' The reason for the spline wear was not determined.

Quoted verbatim from the NTSB record.