Bell 206B N115TV

Summary

On 9 January 2003 at about 15:43 local time, a Bell 206B registered N115TV was involved in an accident near Putnam, Texas, United States. One person was on board and one was seriously injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

9 January 2003 at 15:43

Classification

Accident

Location

Putnam, Texas, United States

Coordinates

32.3761, -99.1700

Aircraft

Bell 206B

Registration

N115TV

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Positioning

Phase of flight

Not recorded

Route

Midland → Grand Prairie

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

FTW03LA080

1 person was seriously injured.

the pilot's failure to properly interpret and confirm a faulty tachometer instrument indication and his improper flare during the ensuing precautionary autorotation, which resulted in a hard landing. Also causal was the failure of the tachometer.

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

Read the full NTSB narrative

The single-engine helicopter impacted the ground hard during a precautionary autorotational landing following an engine overspeed indication. According to the pilot, he observed the rotor rpm increase and attempted to decrease the rpm to no avail. He then reduced the throttle and entered an autorotation. The pilot did not remember hearing an engine or rotor rpm increase. Post-accident examination of the wreckage revealed the dual tachometer indicator had a faulty turbine rpm indication and depicted an overspeed situation when functionally tested. The rotor tach generator and indication tested satisfactorily. Review of the helicopter's maintenance records revealed the dual tachometer indicator was overhauled 39 days prior to the accident, and was installed on the accident helicopter 37 days prior to the accident. No other anomalies were noted with the engine or helicopter. Examination of the engine control unit's nonvolatile information revealed there was no rpm exceedence, and in fact there was an underspeed situation recorded, which was attributed to a high engine rpm indication. The pilot more than likely noted an exceedence in engine rpm on the dual tachometer and interpreted it as a rotor rpm exceedence. He then failed to confirm the indication and autorotated with an operating engine and rotor system.

Quoted verbatim from the NTSB record.