Aviation safety officials issued warnings about potential problems in Rolls-Royce jet engines less than three months before one malfunctioned in mid-air, forcing a superjumbo to make an emergency landing.
The European Aviation Safety Authority (EASA) issued an airworthiness directive on August 4 this year concerning "wear beyond engine manual limits" on the powerful Trent 900 engines.
The directive said the wear could lead to "loss of engine performance with potential for in-flight shut down" and "potential unsafe conditions".
It came as investigators continued a probe into what caused an engine on a Qantas Airbus A380 to shut down mid-flight.
The London to Sydney superjumbo, with 433 passengers and 26 crew on board, made an emergency landing in Singapore after flames were seen pouring from the British made part.
Frightened passengers spoke of debris from one of the four engines piercing the wing of the Airbus A380, the world's biggest passenger aircraft, operated by the Australian airline.
It is the first major safety incident involving the 555-seater double-decker plane which made its first commercial flight in October 2007.
Passenger Lars Sandberg, a DJ from Glasgow, said he was "just happy to be alive" after the plane landed safely back at Singapore airport. Others on the flight said passengers were shouting and crying with relief when the plane touched down safely.
