Inertial navigation is a completely new approach to the navigational problem initiated to a very large extent by the military requirement for a blind navigational system which could not be jammed by, nor give actual assistance to, any potential enemy. It relies for its operation on principles which were understood by Newton, but the practical realisation of a working system has become possible only by the intensive development in both the design and manufacturing techniques of gyroscopes and accelerometers. This development work has, to a considerable extent, been stimulated by Dr. Draper of the Massachusetts Institute of Technology and, although he may not be the inventor of inertial navigation as such, there is little doubt that but for the work carried out under his direction, inertial navigation would still be little more than a dream.

Inertial navigation depends basically on the simple fact that if we can measure the acceleration vector of a body in any convenient axis system, then by carrying out the suitable integration processes we can determine its path in space, its position and its distance from its initial position.