| 词条 | National Security Area |
| 释义 |
In United States aviation, a National Security Area (NSA) is a designated airspace through which flight is discouraged for reasons of national security. Flight through NSAs is not prohibited and no special advance clearance or authorization need be obtained to enter them. However, pilots of aircraft are strongly encouraged to either stay clear of NSAs or obtain prior authorization to pass through them in order to reassure the controlling agency that no threat to national security exists. NSAs are a compromise between normal airspace and restricted or prohibited airspace. NSAs can be temporarily converted into restricted airspace by NOTAMs. On VFR sectional charts, NSAs are delimited by a heavy dashed magenta border and a special notation. See also
1 : Air traffic control in the United States |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。