Plain English Meaning

Equipment on the ground or in space that sends out signals so pilots can figure out where they are and where they're going.

Full Definition

Ground- or space-based equipment that transmits signals pilots use to determine position, track a course, or fly an instrument approach. Common examples include VORs, NDBs, ILS components, DME, and GPS satellites.

Context Anchor

Seen in NOTAMs, which are official notices to pilots, when a navigation aid is out of service, unreliable, or operating differently than expected.

Derivation

Short for 'navigational aids.' 'Navigate' comes from the Latin navigare, meaning to sail or steer a ship. The term moved from sea to sky as borrowed language for finding one's way.