Definition
A Global Positioning System receiver permanently installed in the aircraft's instrument panel, wired into the aircraft's electrical system and typically certified for use as a primary navigation source under specific operational rules (such as IFR enroute, terminal, or approach operations when approved).
Plain English
A GPS unit built into the aircraft's instrument panel rather than a portable handheld one. It is fixed in place, powered by the aircraft, and -- depending on its certification -- can be used for legal navigation, including instrument approaches.
Context Anchor
Seen in instrument procedure and GPS database discussions, especially when the handbook talks about storing routes, waypoints, or approaches in an installed unit.
Derivation
Panel-mounted' simply means fastened into the instrument panel -- the dashboard area in front of the pilot. The phrase distinguishes the unit from a 'portable' or 'handheld' GPS that the pilot brings into the cockpit.
Why Pilots Care
Affects available storage for flight plans, waypoints, and navigation databases, directly influencing how much data can be retained for instrument flight.
Intuition Check
Panel-mounted does not mean a portable GPS clipped near the panel. It means a unit installed in the aircraft’s instrument panel as part of the aircraft’s equipment.
Example Sentence 1
The aircraft's panel-mounted GPS was approved for IFR approaches, so the pilot loaded the RNAV procedure directly from the unit.
Example Sentence 2
Because the panel-mounted GPS is wired into the aircraft, it can send navigation guidance directly to the autopilot.