Inertial navigation has a feature in polar regions, associated with the inability to determine longitude and heading values at the pole point. As a consequence, even small errors of an inertial navigation system lead to unacceptably large errors in computation of these parameters in polar regions. It should be noted that mentioned above problem is the principle limitation for airborne gravity surveys in Arctica and Antarctica. In the paper a methodical technique is described that eliminates marked feature. It is based on implementation of the quasi Earth Centered Earth Fixed reference frame and on the usage of quasi geographic coordinates and quasi orientation angles instead of traditional ones. The mentioned technique adds minor arithmetic operations in standard algorithms of strapdown inertial navigation system.