noun
overnight flight; red-eye flight
Refers to a flight that departs late at night and arrives the next morning. Common in travel contexts.
夜行便で東京からバンコクへ向かった。
I headed from Tokyo to Bangkok on an overnight flight.
夜行便は料金が少し安いことが多い。
Overnight flights are often a little cheaper.
Compound of 夜行 (yakō, 'night travel') and 便 (bin, 'flight' or 'service').