The European Aviation Safety Agency (EASA) today ordered detailed inspections on the wings of the Airbus A380 jumbo jet after cracks were found in brackets that secure the wing’s skin to the aircraft. “This condition, if not detected and corrected, could potentially affect the structural integrity of the aeroplane,” the safety watchdog warns.
EASA says two types of cracks have been found in the L-shaped brackets, called rib feet, that join the A380’s wing surface to the ribs whose profile defines the wing’s cross sectional shape. The first type of rib foot crack was found when the aircraft damaged in last November’s A380 engine-loss incident was being checked out after repairs.
But after subsequent checking of more of the fleet, engineers found a “more significant” form of cracking has developed on the rib feet of some of the aircraft. So EASA has ordered “detailed visual inspections” within the next six weeks for A380 aircraft that have flown between 1300 and 1799 takeoffs and landings – and within just four days for those with over 1800 flight cycles.
There’s a good reason safety watchdogs take no chances with even the smallest of cracks: it was cracks caused by the then unknown phenomenon of metal fatigue that caused the fatal mid-flight breakups of the De Havilland Comet, the first world’s pressurized, aluminium-skinned jetliner, in the 1950s. Tiny cracks around window portholes eventually propagated, bursting the fuselage, after a certain number of flight pressurizations and depressurizations.
While EASA has not said what might happen if A380 rib feet fail owing to cracking, if a section of wing skin were to separate from the plane the debris could potentially damage any critical structure it collides with – like the tailfin.
Australian aircraft engineers also warned Airbus to inspect the aircraft for cracks in early January.