Australian carrier Qantas and Singapore Airlines Friday reassured passengers there was no risk to safety after cracks were found on the wings of several A380 superjumbos, including some in their fleets.
Airbus revealed Thursday that "minor cracks" had been found on some jets, but the European planemaker said they posed no safety problem and recommended a way they could be fixed.
Qantas said the cracks had been found on one of its 10 A380s.
"Minuscule cracking was found in the wing ribs of the Qantas A380 being repaired in Singapore," a Qantas spokeswoman said in a statement.
"No immediate action is required by A380 operators because the cracking presents no risk whatsoever to flight safety."
The cracking on the Qantas A380, which is barely visible to the naked eye and less than a centimetre long, is on the plane that suffered a mid-air engine explosion after take-off from Singapore in November 2010.
"Investigations have found that the cracking is unrelated to the engine failure incident," the Qantas spokeswoman added. "It has now been repaired."
Rival Singapore Airlines said it had also found cracks on the wings of two of its 14 A380 aircraft last year and repaired them.
"Cracks were found on a small number of wing rib feet on an Airbus A380 during inspections in the second half of last year," spokesman Nicholas Ionides said in a statement.
"These pose no safety issue and repairs were carried out on the aircraft.
"Repairs were subsequently carried out on a second aircraft."
Toulouse-based Airbus, the main subsidiary of aerospace giant EADS, said Thursday that minor cracks were found on some non-critical wing rib-skin attachments on a limited number of A380s.
"We have traced the origin. Airbus has developed an inspection and repair procedure which will be done during routine, scheduled four-year maintenance checks," the planemaker said.
"In the meantime, Airbus emphasises that the safe operation of the A380 fleet is not affected."
Qantas said it would comply fully with the formal guidance now being developed by Airbus, which is likely to require A380 operators to inspect wing ribs for this type of cracking every four years.
But the Australian Licensed Aircraft Engineers Association said all A380s should be probed for the cracks on the components, which run all along the wing to keep it structurally sound, as soon as possible.
"If one of them fails during flight, it's going to put an increased load on the others that are most likely cracked as well," union secretary Steve Purvinas told AFP.
"They should be inspecting them all now and repairing them."
The A380 is the world's biggest passenger jet and a key product in Airbus's line-up as it battles its main rival US giant Boeing for the top spot in the world civil airliner industry.
The double-decker plane entered service in 2007 after years of technical delays. There are now 67 in service around the world and, while they have never had a fatal accident, there have been teething problems.