备用机场

bèi yòng jī chǎng shì dāng bù kě néng huò bù shì yí zài yù xuǎn jī chǎng zhuó lù shí kě zuò zhuó lù shǐ yòng de jī chǎng

备用机场，是当不可能或不适宜在预选机场着陆时，可作着陆使用的机场。

Alternate aerodrome, is an aerodrome to which an aircraft may proceed when it becomes either impossible or inadvisable to proceed to or land at the aerodrome of intended landing.