Dead Reckoning (DR) is a method of navigation relying on estimating one's current track, groundspeed and position based on earlier known positions.

Although DR navigation is not much used in practice today, the principles involved may still be employed by pilots to estimate, for example, their ETA for a position ahead, or to estimate an alteration of heading to regain track.

DR navigation is also employed in some electromechanical navigation equipment.

Figure 1: The use of Dead Reckoning navigation.