SYDNEY, July 28 (Xinhua) -- Two aircraft have been damaged in separate collisions with ground equipment at major international airports in Melbourne and Brisbane, Australia. Virgin Australia on Monday ...

比如悉尼（Sydney）、墨尔本（Melbourne）和珀斯（Perth）三地的机场代码分别为SYD、MEL和PER。 但并不是所有三字代码都是这么取来的，因为全球机场太多了，难免会有重复。