FAA Flight Instructor Airplane (FIA)Navigation and AirspaceMedium

A pilot notices a dashed blue line on a sectional chart labeled 'NSA' with a note advising pilots to voluntarily avoid the area. This depicts a:

  1. AMilitary Operations Area
  2. BControlled Firing Area
  3. CProhibited Area
  4. DNational Security Area
Show answer & explanation

Correct answer: D. National Security Area

National Security Areas (NSAs) are depicted with a dashed blue line and request voluntary pilot avoidance to protect ground-based assets. Unlike Prohibited Areas, flight is not automatically forbidden unless a NOTAM temporarily makes it mandatory.

Why the other options are wrong

  • A. MOAs are for military training and depicted with magenta shading, not labeled 'NSA'.
  • B. Controlled Firing Areas are not depicted on charts at all, since activity ceases if aircraft are detected.
  • C. Prohibited Areas mandate no entry and are labeled 'P-', not 'NSA'.

National Security Area (NSA)

Airspace depicted with a dashed blue line where pilots are requested to voluntarily avoid flying, established to protect ground-based assets; may become mandatory via NOTAM.

  • Not automatically restrictive unless a NOTAM makes it mandatory.
  • Depicted with dashed blue border on sectional charts.
  • Different from MOAs, Restricted, and Prohibited areas.

Memory trick: 'Blue dashes, please stay away — NSA asks nicely.'

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