Airbus insists its newest aircraft are safe to fly after the defects were caught at an early stage [AFP]

European air safety officials have ordered checks on entire Airbus A380 fleet after cracks were found in wing component, extending its earlier decision to run a safety check on one third of its 68 superjumbo jets.

The move to inspect all A380s in service on Wednesday came as Qantas Airways, the Australian flag carrier, grounded one of its aircraft for about week following the discovery of 36 separate cracks in wing parts.

The new measures by the European Air Safety Agency (EASA) "reflect the results of a first round of checks, which found cracks in almost all of the planes inspected", Dominique Fouda, an EASA spokesman, said.

"This condition, if not detected and corrected, may lead to a reduction of the structural integrity of the aeroplane," the
EU agency said in its directive to airlines.

Under the new directive, the seven airlines currently operating A380s must carry out Airbus-sanctioned checks and preliminary repairs on every plane before its 1,300th flight.

The first round of inspections, which covered one third of the fleet, applied only to jets that had exceeded that number of flights. Aircraft already approaching or beyond the threshold must now be checked and repaired within weeks.

However, Stefan Schaffrath, an Airbus spokesman, played down the risks of the defects, saying the damaged L-shaped parts, which fix the wing skins to their underlying frame, are "not a primary load-bearing structure".

Cracks have been discovered in a "handful" of the 4,000 such brackets on each aircraft, he said. "The safe operation of this aircraft is not at stake."

Newest planes 'are safe'

By signalling that the flaws are thought to be structural and widespread, the fleet-wide inspection order will refocus attention on faults recently found in flagship jets from both of the world's dominant aircraft makers.

Boeing and Airbus, a division of European Aeronautic Defence & Space Co, maintain that their newest aircraft are safe to fly after problems were caught at an early stage.

Inspections had initially focused on 20 aircraft operated by Singapore Airlines, Air France and Dubai's Emirates - which had logged the most A380 flights in the four years since the world's largest passenger plane entered service.

They will now be also be carried out on superjumbos flown by Qantas, China Southern, Korean Air and Lufthansa.

Qantas grounded one of its 12 A380s after the discovery of two-centimetre (0.8 inch) cracks that were "traced back to a
manufacturing issue", the Australian carrier said on Wednesday.

It was during lengthy repairs to another Qantas jet that the A380 problems first surfaced, following a 2010 engine
explosion that tore open one wing.

Lufthansa's longest-serving A380 has made about 900 flights, Michael Lamberty, a Lufthansa spokesman, said.

"That means we have room to manoeuvre to carry out checks one by one, as part of normal maintenance" he added.