Geomagnetic navigation is an aid of aviation navigation in GNSS-denied environments. In order to reduce the power consumption and cost of airborne equipment, this paper attempts to use INS instead of a 3-axis magnetometer to compensate for magnetic interference in aircraft maneuvers. The errors caused this alternative are analyzed. The installation position of the magnetometer is determined through the magnetic background. Then based on the Tolles-Lawson model, the LS method is applied to calibration. The experimental results calculated by INS are not significantly different from the benchmark results calculated by 3-axis magnetometer and meet the primary standard of dynamic noise in the Criterion of Aeromagnetic Survey. However, the experimental results do not totally reach the IR level of magnetic compensation products. Therefore, this alternative is available to implement, but still needs further improvement.