Patent US 5,789,671

A process and algorithms to determine and correct for the error in azimuth alignment and the errors in "North" and "East" Gyro Drift Rates in an inertial navigator which has been aligned via gyrocompassing, or via the "Stored Heading" technique, with the system "at rest". The process and algorithms may be implemented as an automatic sequence within the system computer to determine and correct the system errors thus determined. These actions make the inertial navigator more accurately represented by the model of an ideal navigation system with a pure and singular initial azimuth misalignment error. Thus the inertial navigator's inital azimuth misalignment error can be more accurately determined and corrected by the model.