one of three mutually perpendicular lines that define the orientation of an aircraft,with one being along its direction of travel and the other two being perpendicular to the direction of travel是什么意思_one of three mutually perpendicular lines that define the orientation of an aircraft,with one being along its direction of travel and the other two being perpendicular to the direction of travel在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句