Definition
A satellite-based radio navigation system that provides aircraft with highly accurate position, altitude, and time information anywhere on Earth. The system works by receiving signals from a network of orbiting satellites; the aircraft's GPS receiver calculates its own position by measuring the time it takes signals to arrive from multiple satellites simultaneously.
Plain English
A navigation system that uses signals from satellites in space to tell the aircraft exactly where it is, how high it is, and what time it is.
Context Anchor
Seen in navigation, flight planning, cockpit displays, and instructor discussions about using modern flight equipment correctly.
Derivation
From 'global' (worldwide) and 'positioning' (locating). Originally developed by the U.S. Department of Defense as NAVSTAR GPS in the 1970s, then opened for civilian use. The name simply describes what it does: positions you globally.
Why Pilots Care
It supplies precise navigation without reliance on ground stations, improving situational awareness and enabling modern instrument procedures.
Analogy
GPS is like a very accurate location service for the airplane. It does not fly the airplane for you; it tells the equipment where the airplane is.
Intuition Check
GPS does not mean the moving map screen itself. The screen may show GPS information, but GPS is the position-finding system behind that information.
Example Sentence 1
The instructor demonstrated how to load a GPS approach into the navigation system before beginning the descent.
Example Sentence 2
GPS guidance kept the aircraft on the correct track during the instrument approach.