And these are designated on aeronautical charts by the letter R followed by a dash and a number.
它们在航空图上用字母 R，后面跟着破折号和数字来表示。
Aeronautical chart
原声例句
传说之境
传说之境
Similarly to the restricted airspace, however, these are designated on aeronautical charts by the letter P followed by a dash and a number.
然而，与限制空域类似，这些空域在航空海图上用字母 P 表示，后跟破折号和数字。
中文百科
航图
航图是一种用于辅助飞机导航的地图，跟船舶的海图、汽车驾驶者的地图原理相似。透过使用这些航图，机师能够判断自己驾驶的飞机所在方位、安全飞行高度、飞行最佳路径、沿途导航设备，以及飞机失事时最佳迫降机场/场地；航图还提供其他例如：无线电频率、空界。
航图通常分为跨海洋航行的长途航图和显示所有陆块的航图。而详细的航图适用于不同阶段的飞行，可能是某机场设施概览文书中覆盖整个大陆的不同的路线图（例如，全球性导航图）。
英语百科
Aeronautical chart 航图
An aeronautical chart is a map designed to assist in navigation of aircraft, much as nautical charts do for watercraft, or a roadmap for drivers. Using these charts and other tools, pilots are able to determine their position, safe altitude, best route to a destination, navigation aids along the way, alternative landing areas in case of an in-flight emergency, and other useful information such as radio frequencies and airspace boundaries. There are charts for all land masses on Earth, and long-distance charts for trans-oceanic travel.