As a result of the development of modern vehicles, even higher accuracy standards are demanded. As known, Inertial Navigation Systems have an intrinsic increasing error which is the main reason of using integrating navigation systems, where some other sources of measurements are utilized, such as barometric altimeter due to its high accuracy in short times of interval. Using a Robust Adaptive Kalman Filter (RAKF), error measurements are absorbed when a Fault Tolerant Altimeter is implemented. During simulations, in order to test the Nonlinear RAKF algorithm, two kind of measurement fault scenarios are examined; continuous bias and measurement noise increment. Under the light of the results, some recommendations are proposed when integrated altimeters are used.