空战 means "aerial combat" or "air battle" and refers to military engagements fought in the sky between aircraft. It combines 空 (air/sky) with 战 (war/battle). It is used in military, historical, and news contexts.
那部电影里的空战场面非常震撼。
nà bù diànyǐng lǐ de kōngzhàn chǎngmiàn fēicháng zhènhàn.
The aerial combat scenes in that movie were extremely stunning.
二战中发生了许多著名的空战。
èrzhàn zhōng fāshēngle xǔduō zhùmíng de kōngzhàn.
Many famous aerial battles took place during World War II.
飞行员在训练中模拟了一场空战。
fēixíngyuán zài xùnliàn zhōng mónǐle yī chǎng kōngzhàn.
The pilot simulated an aerial battle during training.