This paper develops analytical and empirical bounds on the inertial sensor error growth due to the numerical integration of rotation rate and acceleration outputs of various grade inertial measurement units (IMU). The developed error bounds provide an explicit measure of the performance of the IMU when it is the sole means of navigation. Accurate analysis of inertial sensor error growth is essential to ensuring the effectiveness of the optimal synergy of GPS and inertial measurements, as success is often limited by the availability of GPS signals in harsh environments. Studies of inertial sensors and their associated error modes have been developed resulting in the wide use of these models for use in GPS/INS algorithms. This paper presents an analysis of the IMU models to investigate the behaviors of inertial navigation error growth due to the subsequent integrations of the raw measurements in dead reckoning. The main purpose of this study is to provide quantitative specification on the degradation of navigation solutions when dead reckoning with IMUs. The parameters characterizing the sensor models for which the error analysis is performed are identified using autocorrelation and Allan variance techniques and the resulting analytical based formulations are validated using Monte Carlo simulation methods.