top of page


As pilots, we are always learning rather it’s something new that just came out from the FAA (regulations, Airworthiness Directives, Advisory Circulars, etc.), a new aircraft or even a sectional chart change or new approach plate. Whatever it maybe we will never know it all. As we constantly look at VFR sectional charts, TAC (Terminal Area Charts), something new always seems to appear. In this case, it is a National Security Area. These areas are to be avoided by pilots.

National Security Areas are a section of airspace of defined vertical and lateral dimensions, which is designated on VFR sectional charts that require an increase in security or safety for current ground facilities. Sometimes NSA well establish a NOTAM for even more security. NSA are depicted on sectional charts by either a thick magenta dashed line (don’t get this confused with Class Echo airspace, which are thin magenta dashed lines), or shaded area along with an information box.

National Security Area verses Class E airspace

If we take a look at the San Francisco sectional chart, there is an NSA just east of the Livermore Municipal Airport (KLVK). The NSA covers the Lawrence Livermore National Laboratory, which is where research is conducted on nuclear weapons, energy, environmental and scientific research. With the type of research and technology being conducted at this facility, pilots are required to avoid the area and fly above 800 feet AGL over the facility.

Lawrence Livermore National Laboratory

Let’s look at another NSA depicted on the Salt Lake City sectional chart. This NSA is for the Idaho National Laboratory located west of the Idaho Falls Regional Airport (KIDA). Which also conducts nuclear energy and research. Pilots are required to avoid the area and fly above 6,000 feet MSL over the facility.

Idaho National Laboratory

Even some NSA are so small that they are hard to see on a sectional chart such as the one located next to the city of Oak Ridge, TN. You can find this NSA on the Atlanta sectional chart northwest of Knoxville, TN. Again, pilots are required to avoid the area and fly above 3,000 feet MSL over the facility.

Oak Ridge, TN.

Always review your sectional charts and any changes. You never know what you may find and learn, even if you are bored.


Leave your comments below


bottom of page