METHODS AND APPARATUS FOR INSTALLATION ALIGNMENT OF EQUIPMENT

A method for installation alignment of an inertial reference unit (IRU) with vehicle axes when the IRU is installed within the vehicle is provided. The vehicle axes include roll, pitch, and yaw axes. The method includes recording vehicle angular position data including roll and pitch, using an angular position measurement device with the vehicle being in a starting position, recording IRU data including roll and pitch, receiving measured nose plunge data, computing initial roll and pitch misalignment corrections, applying initial roll and pitch misalignment corrections to measured nose plunge data. A nose plunge yaw misalignment is determined using corrected nose plunge data and utilized to adjust the assumed heading reference.