Abstract The mathematic methods of position and velocity errors in Inertial Navigation System caused by disturbing gravity vector are discussed.Through the calculation of the data of a certain oceanic area where the gravity anomalies are known the magnitude and characteristics of the errors are also studied. The output information of gravity sensor in GravityAided Inertial Navigation System can be applied in gravity matching to correct gyroshifting errors of inertial navigation cumulated with time and also be used in gravity correction to eliminate Schuler errors caused by the fact that the normal gravity rather than the actual gravity is used in the mechanical equation.
