||Gyro drift occurs in inertial navigation systems (INS, in area navigation/RNAV). An INS system consists of the inertial platform, interior accelerometers and a computer...
There are two sorts of gyro drift:
- Leveling Gyro Drift : the random precession of gyros will tend to turn the platform away from the horizontal causing an oscillation action as the accelerometers try to correct. This oscillation, depending on its period, will cause velocity and subsequent distance errors.
- Azimuth Gyro Drift : Small position errors may occur due to azimuth gyro drift. However, gyro drift about the azimuth axis produces in-flight azimuth errors that are small compared to the initial misalignment errors in azimuth. (source: PilotFriend.com)