Sydney, Australia (CNN) -- A design issue rather than poor maintenance is likely to blame for the mid-flight failure of a Qantas airliner's engine, the CEO of the Australian carrier said Friday.
One of the four engines on the Qantas Airbus A380 shut down six minutes after takeoff Thursday from Singapore's Changi Airport, forcing it to return and make an emergency landing.
The plane -- with 440 passengers and 26 crew members -- was headed to Sydney, Australia. But while above the western Indonesian island of Batam, part of the engine's covering, or cowling, tore off.
"This issue does not relate to maintenance; this is an engine issue," CEO Alan Joyce told reporters Friday. "And the engines have been maintained by Rolls-Royce since they've been installed on the aircraft."
"So we believe that this is probably most likely a material failure or some sort of design issue that we're tracking and trying to understand," he added. "We don't believe this is related to maintenance in any way."
On Friday, Airbus announced that it had asked all operators of A380s with Rolls-Royce engines to inspect them as a precaution.
Following the Qantas CEO's comments, a Rolls-Royce spokesman referred back to his company's earlier news statement, which said:
"Since Qantas QF32 suffered an engine failure and returned safely to Singapore Changi Airport, we have been working closely with our customer and the authorities. In situations like these, Rolls-Royce has well established processes to collect and understand information relating to the event and to determine suitable actions."
After the incident, Qantas -- Australia's national airline -- grounded its Airbus A380 fleet.
The airline said flights of the twin-deck planes -- the world's largest airliners -- will remain suspended until an investigation is complete.
On Friday, Joyce said Qantas hopes to resume A380 flights within 48 hours, after completing engine safety checks.
"We believe over the next 24 to 48 hours, those checks will be complete on all of the A380s, and if we don't find any adverse findings out of the checks, the aircraft will resume operations," he said.
Qantas has six A380s in its fleet of 191 planes. Airbus will at some point deliver 14 more, the airline said.
Passengers on the detoured Qantas flight spent the night in Singapore, then flew to Australia on Friday.
"Passengers left on a special Qantas flight at 10:30 a.m. local back to Sydney," said airline representative Ashley Edwards Knapp.
CNN's Zain Verjee and Ben Brumfield contributed to this report.