By S.L. Fuller | October 23, 2017
The Australian Transport Safety Bureau has released its final report on the 2015 emergency landing of a Eurocopter/Airbus Helicopters AS350 BA. One of the findings pointed to a failure of the Tubromeca/Safran Helicopter Engines Arriel 1B engine.
The bureau said the helicopter, registered VH-SFX, was on a mission to identify noxious plants in dense forests in Queensland Nov. 2, 2015. To perform the task, the aircraft needed to operate at a low altitude and airspeed. During its fourth flight of the day, the bureau said the helicopter momentarily yawed twice in an “uncommanded and unusual way.” The pilot then ceased the operation, climbed and increased forward airspeed. The aircraft then headed back toward the base. Before arrival, the chip detector light came on, prompting the pilot to search for a suitable landing area, the bureau said. As the helicopter continued to climb, the engine stopped producing power. The pilot was able to land the aircraft using an emergency autorotation. The three passengers received no injuries or minor injuries, and the pilot sustained “serious” back injuries, according to the bureau. The helicopter also sustained substantial damage.
The bureau’s findings include:
In response, the bureau said Safran Helicopter Engines amended its procedure manual to include systematic cleaning of the power turbine front bearing assembly oil jet and oil jet supply pipe. The company has also initiated a number of training and process changes to ensure the adhesive bonding between the power turbine and the rear nut is maintained during service.