April 16, 2013
The European Aviation Safety Agency (EASA) is slowly nearing the issuance of an airworthiness directive (AD) that will include guidelines on how Airbus A380 operators have to modify wings of the in-service fleet.
EASA yesterday released a notification of a proposal to issue an airworthiness directive that is based on 14 service bulletins, five of which have yet to be issued and another three that are being modified.
The AD itself will be published once all the service bulletins are finalized; the consultation period for the proposed AD ends on May 13.
The process addresses the planned modification of wing rib feet and other components inside the wings of in-service A380s, and aircraft that are in final assembly but still built to the old standards.
According to the proposed AD, EASA will require some modifications to be performed before an aircraft has accumulated 700 cycles, while other retrofits can wait for up to 17,300 flight hours. For some other work, EASA is allowing up to six years for modifications. The timing depends on the specific parts and the exact production standard of the affected aircraft.
Airbus has prepared a retrofit and forward fit program that is intended to permanently eliminate the development of Type 2 cracking of wing rib feet in certain areas of the A380 wing. The manufacturer has identified temporary repairs for the in-service fleet, which have to be repeated after a certain amount of flight cycles.
The in-service fleet and an estimated 120 not-yet-delivered aircraft are to receive a permanent fix beyond the temporary repairs that includes adding horizontal stiffeners below the access panel on certain ribs and modifying the rib feet booms with new re-sized rib feet booms now made of aluminum alloy 7010.
Ribs 48 and 49 also are to be replaced by new components made of aluminum alloy 7010.
The retrofit is to ensure the A380’s service life is restored to the full 19,000 cycles. The work is performed by several MRO providers, which Airbus has identified.
Airbus also pays for the work, but the manufacturer and airlines have been discussing further compensation because the modifications take aircraft out of service for several weeks unless performed in several steps during C-checks. Modification of several aircraft has already started.