Inertial navigation systems rely on which sensors to determine motion?

• A. Pressure Altimeter And Airspeed Indicator
• B. Accelerometers And Gyroscopes
• C. Magnetometer And ADF
• D. Pitot Tube And Static Port

Answer: (B)

Inertial navigation systems determine motion from internal measurements of acceleration and rotation. The core sensors are accelerometers, which detect linear acceleration along three axes, and gyroscopes, which sense angular rate about those axes. By measuring how the aircraft’s velocity and orientation change over time, the system integrates these signals to update position and attitude, all without relying on external references. That self-contained approach is what makes accelerometers and gyroscopes the essential sensors for an INS.

The other options describe instruments that infer motion from air properties or external references, not direct inertial measurements: a pressure altimeter and airspeed indicator use ambient air pressure to estimate altitude and speed; magnetometer and ADF relate to magnetic heading and radio navigation cues; and the pitot tube with the static port provide airspeed and altitude indications via pressure readings.