1. A system of air navigation whereby a flight is accomplished using a single value of compass heading. The heading must be so determined that it compensates for the net effect of the wind en route. It should also be noted that a single-heading course rarely coincides with a great-circle course, except in grid navigation. Single-heading navigation is not necessarily economical in terms of least time, but its advantage lies in its simplicity. Compare single drift correction. 2. Same as aerologation.