A Singapore Airlines Airbus A-380 has its engine checked, at the Airport Zuerich, in Switzerland, in this Nov. 4, 2010, file photo. Tests uncovered oil stains in three Rolls-Royce engines on Singapore Airlines' A380 superjumbos, prompting the airline to yank the planes from service Wednesday Nov. 10, 2010 just two days after Qantas announced troubling oil leaks on their A380s. (AP Photo/Keystone, Steffen Schmidt, File)