Aerospatiale AS-350D N36062

Summary

On 18 May 1983 at about 15:56 local time, a Aerospatiale AS-350D registered N36062 was involved in an accident near Venice, Louisiana, United States. One person was on board and one died. The aircraft was destroyed. No probable cause statement is available for this record.

Date

18 May 1983 at 15:56

Classification

Accident

Location

Venice, Louisiana, United States

Coordinates

29.2701, -89.3502

Aircraft

Aerospatiale AS-350D

Registration

N36062

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Ferry

Phase of flight

Not recorded

Route

West Delta → Venice

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

FTW83FA238

1 person died.

The NTSB has not published a probable cause for this record. No probable cause statement is present in the source data.

Nothing about the cause is stated here that is not in the source record.

Read the full NTSB narrative

THE ACFT CRASHED INTO A SWAMP WITH LOW ROTOR RPM AFTER A FAILURE OF THE ACCESSORY GEARBOX POWER OUTPUT GEAR. THE PILOT RADIOED AN EMERGENCY CALL SAYING HE WAS EXPERIENCING SEVERE VIBRATIONS AND WAS LANDING. A FEW SECONDS LATER, HE RADIOED THAT HE WAS CRASHING. RESCUE ACFT FOUND THE HELICOPTER ON ITS RIGHT SIDE PARTIALLY IN WATER. THERE WAS EVIDENCE THAT THEFAILED GEAR BOX RESULTED IN LOW ROTOR SPEED WHICH WAS NOT RECOVERED DUE TO LACK OF ALTITUDE AT THE TIME OF FAILURE. AN INVESTIGATION REVEALED THAT THE POWER TURBINE OUTPUT (PTO) GEAR, PN 4-081-044-15, FAILED FROM LOW STRESS, HIGH CYCLE FATIGUE. THE FATIGUE ORIGINATED AT A POINT WERE REHARDENING BURNS CAUSED BY GRINDING WERE PRESENT. THIS GRINDING WAS ACCOMPLISHED DURING MANUFACTURING OF THE GEAR AFTER IT HAD BEEN CARBURIZED. THE PROCEDURE SHOULD HAVE BEEN ACCOMPLISHED PRIOR TO CARBURIZATION WHEN THE MATERIAL SURFACE WAS MUCH SOFTER & LESS SUSCEPTIBLE TO GRINDING BURNS.

Quoted verbatim from the NTSB record.