What is the primary function of an inertial navigation system (INS)?

The primary function of an inertial navigation system (INS) is to determine position using gyroscopes or accelerometers. This system operates by using these devices to measure the specific forces acting on an aircraft and its rotation relative to a fixed axis. By integrating these measurements over time, the INS can accurately compute the aircraft's position, velocity, and attitude without relying on external signals, making it a crucial technology for navigation, especially in environments where GPS signals may be unreliable or unavailable.

The other options pertain to different functions that do not align with the core purpose of an INS. Visual navigation involves the use of visual cues rather than internal measurements, enhancing cockpit communication is unrelated to positional data, and managing fuel efficiency incorporates various systems but is separate from an INS's functionality.