ROLLS-ROYCE Plc repeatedly failed to identify a defect that caused one of its engines to explode on a Qantas Airways Ltd aircraft carrying more than 400 people over Indonesia three years ago, an Australian safety regulator found.

In its final report on the incident, the Australian Safety Transport Bureau said the company missed multiple opportunities to detect the faulty component which almost certainly would have caused the Airbus A380 to crash had it not been for the exceptional skill of the pilots.

It was the first major safety scare to affect the A380, and led to Qantas suspending its operation of the aircraft for around three weeks. The ASTB report could lead to broader requirements for new aircraft certification around the world.

"Those opportunities were missed for a number of reasons, but generally because of ambiguities within the manufacturer's procedures and the non-adherence by a number of the manufacturing staff to those procedures," the report said yesterday.

The A380 was flying from Singapore to Sydney with 433 passengers and 26 crew on board when one of its four engines blew up, spraying the plane with shrapnel and dropping chunks of debris on Indonesia's Batam island.

A large section of a turbine disc landed on a house, but there were no injuries to anyone on the plane or on the ground.

The plane returned to Singapore and landed with limited controls, stopping just 150 meters before the end of the runway with four blown tires, brakes heated to 900 degrees Celsius and fuel leaking.

After the incident, Rolls-Royce found that a large number of the defective component - the support assemblies manufactured with pipes that feed oil into the engine bearing - did not conform to design specifications. The parts came from a facility in the UK.

Rolls-Royce missed several opportunities to identify the potential for cracking in the oil feed stub pipes during the production and post-production phase, the ASTB said.