Which device is used on a UAS to determine the roll, pitch, and yaw of the aircraft?

The Inertial Measurement Unit (IMU) is essential for the operation of an Unmanned Aircraft System (UAS) because it combines multiple sensors to provide critical orientation data, specifically roll, pitch, and yaw. The IMU typically includes accelerometers and gyroscopes, which work collaboratively to detect and measure the aircraft’s movement in three-dimensional space. This data is crucial for stabilizing the aircraft and ensuring precise navigation and control.

Although a gyroscope is a component of the IMU and contributes to measuring angular velocity, it does not encompass all the measurements provided by the IMU. The GPS Module primarily focuses on location and speed over ground rather than orientation, while the altimeter is used to measure altitude, not orientation changes. Thus, the comprehensive capability of the IMU to track all three axes of motion—roll, pitch, and yaw—makes it the correct answer in this context.