Fairchild Hiller FH-1100 N4035G

Summary

On 8 June 2006 at about 17:32 local time, a Fairchild Hiller FH-1100 registered N4035G was involved in an accident near Navarre, Florida, United States. 2 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

8 June 2006 at 17:32

Classification

Accident

Location

Navarre, Florida, United States

Coordinates

Not recorded

Aircraft

Fairchild Hiller FH-1100

Registration

N4035G

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Navarre → Century

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

MIA06LA126

Nobody was injured.

The inadequate manufacturing of the plates of the tail rotor tension-torsion bar assembly resulting in fatigue failure.

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

Read the full NTSB narrative

While flying in straight and level flight at 600 feet and approximately 100 miles-per-hour, undetected fatigue cracks in the stainless steel plates of one of the tail rotor blade tension-torsion bars resulted in in-flight separation of one tail rotor blade, and subsequent structural separation of a portion of the ventral fin. The pilot executed an autorotative landing to shallow water and there were no injuries to the pilot or pilot-rated passenger. Eight of the 11 stainless steel plates of the tension-torsion bar assembly exhibited fatigue which originated from stress risers created during the manufacturing process (punching) of the holes of the plates. Reaming of the holes did not eliminate the surface created during the punching process. This problem was previously noted to exist and corrective action was taken in the form of an airworthiness directive (AD), but the AD was not applicable to the accident helicopter because the serial number of the accident tension-torsion bars was outside of the scope of the AD.

Quoted verbatim from the NTSB record.