Agusta AW119 MKII N802SM

Summary

On 20 February 2015 at about 13:50 local time, a Agusta AW119 MKII registered N802SM, operated by ERA Helicopters LLC, was involved in an accident near Gulf of Mexico, 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

20 February 2015 at 13:50

Classification

Accident

Location

Gulf of Mexico, United States

Nearest airport

Houma-Terrebonne (HUM)

Coordinates

28.5000, -91.3000

Aircraft

Agusta AW119 MKII

Registration

N802SM

Category

Helicopter

Engines

1

Operator

ERA Helicopters LLC

Operating rule

Part 135: Air Taxi & Commuter

Phase of flight

Not recorded

Route

Houma → Gulf of Mexico

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CEN15LA156

Nobody was injured.

The fracture of the tail rotor pitch change link due to excessive bearing rotational friction, which resulted from the bearings being installed in exceedance of the maximum allowable torque during the last overhaul of the pitch change link.

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

Read the full NTSB narrative

The commercial pilot was conducting an on-demand air taxi helicopter flight. The pilot reported that, while in cruise flight over water, the helicopter experienced an abrupt, uncommanded left yaw. The pilot returned to the departure airport and performed a run-on landing. A postflight examination of the helicopter revealed that one of the tail rotor pitch change links (PCL) was fractured. A review of maintenance records revealed that the fractured PCL had recently been overhauled and installed on the helicopter and that it failed 14.8 flight hours since overhaul. Examination of the PCL revealed that it had fractured due to undetected fatigue cracking that appeared to be the result of bending loads caused by stiff bearings. The stiffness was likely the result of the lack of control of the bearing replacement process. The PCL bearing replacement procedures, which incorporated rotational torque inspection and bearing staking procedures, were contained in the overhaul manual; these procedures were revised about 3 months before the accident, and the overhaul facility used the revised procedures during the replacement of the PCL. Examination of the PCL revealed that both of the bearings exceeded the maximum allowable rotational torque by at least two times the maximum allowed. Based on the findings of this investigation, the PCL manufacturer corrected the figure in the PCL replacement procedures to display the correct method of inspecting spherical bearing rotational torque.

Quoted verbatim from the NTSB record.