Inertial Navigation System

An inertial-navigation system is a navigation aid that uses a computer and motion sensors to continuously track the position, orientation, and velocity (direction and speed of movement) of a vehicle without the need for external references. Other terms used to refer to inertial navigation systems or closely related devices include inertial guidance system, inertial reference platform, and many other variations.
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Noun
1. a system to control a plane or spacecraft; uses inertial forces
(synonym) inertial guidance system
(hypernym) system
(part-holonym) spacecraft, ballistic capsule, space vehicle

An Area Navigation (RNAV) system which is a form of self-contained navigation. (FAA4)

A self-contained navigation system using inertial detectors, which automatically provides vehicle position, heading and velocity. 1/10/80

Système de navigation autonome, utilisant des détecteurs inertiels, qui fournit automatiquement la position d'un véhicule, son cap et sa vitesse. 1/10/80

An RNAV system which is a form of self-contained navigation.
(See Area Navigation/RNAV.)