NATIONAL AIRSPACE SYSTEM (NAS)
The common network of US airspace; air navigation facilities, equipment and services, airports or landing areas; aeronautical charts, information and services; rules, regulations and procedures, technical information, and human resources and material. Included are system components shared jointly with the military.
【友情提示】
（1）请先注册或登录后再下载附件。
（2）请使用电脑PC/Mac桌面浏览器下载附件，以获得最佳兼容性。推荐使用Chrome。
（3）如使用手机/平板自带浏览器访问，
请先下载、然后在本机存储中打开文件，附件不支持在线预览、显示或播放。
