Qantas has justified last week's grounding of its six Airbus A380s over an uncontained in-flight engine failure, as investigators assess the extent of damage to the aircraft involved.

While neither Lufthansa nor Singapore Airlines - the other two operators of Rolls-Royce Trent 900-powered A380s - chose such a drastic course of action, Qantas chief Alan Joyce insisted that he was "absolutely making the right decision".

Evidence of a substantial failure of the inboard left-hand engine emerged after the Qantas crew opted to return flight QF32 to Singapore shortly after departing for Sydney on 4 November.

It had shed large sections of the shroud surrounding the high-pressure section of the engine while flying over Indonesia but the aircraft had also sustained peripheral damage to its wing surface. Its landing-gear doors, normally hydraulically stowed, were extended and the jet's leading-edge slats did not appear to have deployed.

Parts recovered from the ground appear to include fragments of a disc assembly.

The two-year-old jet (VH-OQA) was the first A380 delivered to Qantas, in September 2008, and it had conducted 831 flights before the incident, clocking up 8,165h.

It is one of 20 Trent 900-powered A380s delivered to Qantas, Singapore Airlines and Lufthansa.

Rolls-Royce has advised operators to conduct some "basic precautionary engine checks" while it seeks to understand the source of the failure, stating that the in-service fleet is "small and relatively new".

Singapore Airlines and Lufthansa subsequently carried out examination of their aircraft but neither opted to withdraw the type from service.

Another 17 A380s, with Engine Alliance GP7200 powerplants, in service with Emirates and Air France, are unaffected.

Australian investigators are to head the inquiry, supported by Singaporean and Indonesian representatives as well as Airbus and the French BEA bureau.

Source: Flight International