directorate of flight safety research飞行安全: air safety研究: study; research处: place飞行安全: air safety; flight calibration; flight safety飞行安全奖: flight safety award下载手机词典可随时随地查词查翻译关注微信公众号：chachacidian，回复:飞行安全研究处，即可在微信中查询翻译
